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Comprehensive Summary: Treponema is a Gram‐negative anaerobic bacterium, among which the pathogenic Treponema can cause various diseases, such as venereal syphilis (Treponema pallidum), yaws (Treponema carateum), and oral diseases (Treponema denticola and Treponema medium). Although different from conventional lipopolysaccharides, the extracellular glycoconjugate of Treponema may still be a potential antigen and provide a candidate for vaccine development. Hence, we completed the first chemical synthesis of Treponema medium ATCC 700293 tetrasaccharide precursor containing L‐ornithine (L‐Orn) and D‐aspartic acid (D‐Asp) derivatives. The efficiency of non‐reducing end disaccharide formation has been improved by optimizing the assembly of the protecting groups in the donors and acceptors. Our [3+1] glycosylation strategy attempted to reduce the length of the acceptor to increase the nucleophilicity of the hydroxyl group, thereby improving the efficiency of synthesizing the target tetrasaccharide. The L‐Orn derivative was introduced at the final stage due to its influence on the glycosylation stereospecificity and efficiency. Therefore, the successful introduction of two amino acid derivatives and the synthesis of a tetrasaccharide precursor with complex functional‐group modifications have provided valuable insights for synthesizing other complex bacterial glycans. [ABSTRACT FROM AUTHOR]

Urinary tract infections are a common diagnosis in dogs presenting to veterinary practice. Veterinarians often treat suspected infections empirically, either in the absence of culture and susceptibility testing results or whilst waiting for them. This study aimed to identify the bacteria most frequently isolated from canine urinary samples and their antimicrobial susceptibility patterns in South East Queensland (SEQ) to help guide responsible empirical antimicrobial prescription by the veterinary community in this geographical location. Cumulative antibiograms were generated from the results of 1284 culture‐positive urinary samples in SEQ, obtained from a commercial veterinary laboratory over a 5‐year period. Escherichia coli was the most commonly isolated bacterial species (43%), followed by Staphylococcus spp. (23%), Proteus spp. (21%) and Enterococcus spp. (10%). Of the six most common isolates, 97% had susceptibility to at least one low‐importance antimicrobial. Susceptibility to the low‐importance and first‐line antimicrobial recommendation, amoxicillin, was 81% for E. coli and 24% for Staphylococcus spp. Susceptibility of both E. coli and Staphylococcus spp. to medium‐importance and commonly recommended empirical antimicrobials, trimethoprim sulphonamides and amoxicillin–clavulanic acid was ≥85% and >92% for high‐importance antimicrobials enrofloxacin and ceftiofur. Of the E. coli and Staphylococcus spp. isolates, 8.8% and 4%, respectively, were considered multidrug resistant. There was no increase in resistance to antimicrobials detected over the study period. Susceptibilities suggest low‐ and medium‐importance antimicrobials remain acceptable first‐line empirical treatments. However, this should be continually assessed and updated using local surveillance data. [ABSTRACT FROM AUTHOR]

Fresh insects in the form of paste can be conveniently utilised for further food preparations and processing at both household and industrial levels. However, due to the high moisture content and particular physiochemical properties, insect paste is highly unstable and susceptible to significant quality changes during storage. The aim of this study was to evaluate the microbiological and physicochemical stability of high hydrostatic pressure (HHP) treated Tenebrio molitor paste stored at different modified atmosphere packaging (MAP) conditions. Three different MAP compositions and normal air were applied. pH, colour, lipid oxidation, fluorescence spectra and microbiological parameters were evaluated along 28 days of refrigerated storage (4 °C). HHP treatment (600 MPa, 5 min) resulted in a significant reduction in mesophilic aerobic bacteria, anaerobic bacteria and yeast and mould counts. Growth of mesophilic aerobic and anaerobic bacteria remained low for 7 days at 4 °C, regardless of the applied atmospheric conditions, while high microbial growth was observed after 14 days without any significant differences among the treatments. The number of mesophilic spores remained low throughout the entire storage period when MAP was applied, whereas high values were observed after 28 days in the samples stored in normal air. Listeria monocytogenes, Salmonella spp. and Escherichia coli were not detected in any of the samples, nor in the raw paste. Lipid oxidation was initiated by the HHP treatment and displayed an increasing trend during the storage period, although the oxidation levels were lower in the MAP without oxygen compared to the normal air packaging and in MAPs with high O2 or CO2 levels. Fluorescence spectroscopy showed high potential for rapid detection of chemical changes in insect products during processing and storage. Overall, this study showed that MAP can effectively be applied on HHP-treated insect paste to extend its storage period. Absence of oxygen has been identified as a crucial factor in achieving reduced microbial growth and ensuring high physiochemical quality of the final product. Therefore, the present research offers a valuable insight for creating new edible insect-based products within the food industry. [ABSTRACT FROM AUTHOR]

Aim: Blood–brain barrier (BBB) disorder is one of the early findings in cognitive impairments. We have recently found that Porphyromonas gingivalis bacteraemia can cause cognitive impairment and increased BBB permeability. This study aimed to find out the possible key virulence factors of P. gingivalis contributing to the pathological process. Materials and Methods: C57/BL6 mice were infected with P. gingivalis or gingipains or P. gingivalis lipopolysaccharide (P. gingivalis LPS group) by tail vein injection for 8 weeks. The cognitive behaviour changes in mice, the histopathological changes in the hippocampus and cerebral cortex, the alternations of BBB permeability, and the changes in Mfsd2a and Cav‐1 levels were measured. The mechanisms of Ddx3x‐induced regulation on Mfsd2a by arginine‐specific gingipain A (RgpA) in BMECs were explored. Results: P. gingivalis and gingipains significantly promoted mice cognitive impairment, pathological changes in the hippocampus and cerebral cortex, increased BBB permeability, inhibited Mfsd2a expression and up‐regulated Cav‐1 expression. After RgpA stimulation, the permeability of the BBB model in vitro increased, and the Ddx3x/Mfsd2a/Cav‐1 regulatory axis was activated. Conclusions: Gingipains may be one of the key virulence factors of P. gingivalis to impair cognition and enhance BBB permeability by the Ddx3x/Mfsd2a/Cav‐1 axis. [ABSTRACT FROM AUTHOR]

Summary: The growing consumption of untreated juices has increased the outbreaks related to Salmonella spp., Escherichia coli O157:H7 and Listeria monocytogenes. Although these pathogens are not in favourable conditions in fruit juices, cases of survival in acidic environments have been reported in fruit and vegetable juices. Thus, this study has evaluated the microbiological quality (total aerobic mesophilic microorganisms (TAM), moulds and yeasts, total coliforms (TC) and E. coli populations) and investigated the occurrence of foodborne pathogens (Salmonella spp. and L. monocytogenes) in 100 fresh (blended) and self‐service (monovarietal) untreated juices. Concerning the obtained results, pH was higher for fresh juices than for self‐service juices. The results showed great variability in TAM, moulds and yeasts and TC populations. For TAM, the results ranged from 1.7 to 7.4 log cfu mL−1. Values for moulds and yeasts, ranged from below detection limit (<10 cfu mL−1) to 5.9 log cfu mL−1. And for TC, results went from below detection limit (<1 cfu mL−1) to 4.4 log cfu mL−1. However, significant differences were only observed between the two types of samples in TC, being higher in fresh juices than in self‐service juices. For E. coli enumeration, all the samples were below the detection limit (1 cfu mL−1). Finally, no Salmonella spp. or L. monocytogenes were detected in 25 mL of sample. All analysed samples complied the requirements from European regulation. [ABSTRACT FROM AUTHOR]

The aim of this study is the determination some quality parameters of grape and mulberry pestils (leathers) sold in Elazig. For this purpose, a total of 45 fruit pestil samples, of which 23 were grape pestils and 22 were mulberry pestils, were analyzed for their physical properties, chemical properties, and microbiological characteristics. In grape and mulberry pestils, the average L* (lightness/darkness) values were 42.72 and 44.81, a* (redness) values were 10.29 and 9.07, and b* (yellow) values were 20.90 and 20.90, respectively. In grape and mulberry fruit pestil samples, the thickness values were 1.62 and 1.34, pH values were 3.82 and 4.75, acidity values (as citric acid) were 0.63 and 0.22%, aw values were 0.602 and 0.627, dry matter values were 68.78% and 72.99 %, ash values were 2.25% and 0.64%, insoluble ash values in 10% HCl were 0.20 and 0.29, and Brix values were 18.83 and 19.36, respectively. TMAB, coliform, Staphylococcus-Micrococcus, and yeast-mold counts were found to be 4.72 and 4.48, 1.30 and 1.89, 2.11 and 2.12, and 2.04 and 2.11 log10 cfu/g, respectively, in all samples examined. In 14 of the samples (31.11%), the total number of mesophilic aerobic microorganisms was found to be >5 log10 cfu/g. Escherichia coli and Salmonella spp. were not found in any of the samples. However, the samples were found to contain significant levels of yeast-mold. There was no difference between the groups in microbiological terms in statistical analysis (P > 0.05). According to the current study, there was no standard production and not enough hygiene rules were observed in the pestil production process in family businesses in Elazig. On the other hand, essential information was obtained on some physical, chemical and microbiological quality parameters of grape and blackberry pulps sold in markets and stores in Elazig. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microbial overlap in biowaste workers' exposure via air and species on hands. • Biowaste links to lactic acid bacteria and compost to A. fumigatus exposure. • Some species have previously been linked to occupational health issues. • Several risk class 2 species present; most species cannot be risk evaluated. • Different species compositions in various particle size fractions. This study aims to investigate the microbiological working environment of biowaste workers, focusing on airborne fungal and bacterial species exposure, size distribution, and species on workers' hands. The research, conducted across six plants with 45 personal exposure assessments, revealed a total of 150 bacterial species and 47 fungal species on workers' hands, including 19 and 9 species classified in risk class 2 (RC2), respectively. Workers' exposure analysis identified 172 bacterial and 32 fungal species, with several in RC2. In work areas, 55 anaerobic bacterial species belonging to RC2 were found. Different species compositions were observed in various particle size fractions, with the highest species richness for anaerobic bacteria in the fraction potentially depositing in the secondary bronchi and for fungi in the pharynx fraction. The geometric mean aerodynamic diameter (D G) of RC2 anaerobic bacteria was 3.9 µm, <1.6 µm for Streptomyces , 3.4 µm for Aspergillus , and 2.0 µm for Penicillium. Overlapping species were identified on workers' hands, in their exposure, and in work areas, with Bacillus amyloliquefaciens, Leuconostoc mesenteroides, Bacillus cereus, Enterococcus casseliflavus , and Aspergillus niger consistently present. While the majority of RC2 bacterial species lacked documented associations with occupational health problems, certain bacteria and fungi, including Bacillus cereus, Escherichia coli, Enterobacter, Klebsiella pneumonia, Aspergillus fumigatus, Aspergillus niger, Aspergillus flavus, Lichtheimia corymbifera, Lichtheimia ramosa, and Paecilomyces variotii, have previously been linked to occupational health issues. In conclusion, biowaste workers were exposed to a wide range of microorganisms including RC2 species which would deposit in different parts of the airways. [ABSTRACT FROM AUTHOR]

Background: Cutibacterium acnes is an anaerobic bacterium mostly implicated in cutaneous and body-implant infections. Splenic abscess is a rare entity and C. acnes abscesses have only exceptionally been reported. We describe a spontaneous splenic C. acnes abscess in an immunocompetent man with no predisposing factors or identified portal of entry. His isolates were subjected to single-locus sequence typing (SLST) to explore their genetic relatedness and better understand this rare infection. Case presentation: A splenic abscess was diagnosed on a computed-tomography scan in a 74-year-old man with chronic abdominal pain. No risk factor was identified. Abscess-drained pus and post-drainage blood cultures grew C. acnes. SLST of abscess and blood isolates showed that they belonged to the same C. acnes SLST type C1 found in normal skin and rarely in inflammatory skin disease. Specific virulence factors could not be identified. Conclusion: C. acnes abscesses are extremely rare and can develop in immunocompetent patients without an identifiable portal of entry. Molecular typing of clinical isolates can help confirm infection (versus contamination) and enables genetic background comparisons. Further research is needed to understand C. acnes tropism and virulence. [ABSTRACT FROM AUTHOR]

Understanding how microbial lipidomes adapt to environmental and nutrient stress is crucial for comprehending microbial survival and functionality. Certain anaerobic bacteria can synthesize glycerolipids with ether/ester bonds, yet the complexities of their lipidome remodeling under varying physicochemical and nutritional conditions remain largely unexplored. In this study, we thoroughly examined the lipidome adaptations of Desulfatibacillum alkenivorans strain PF2803T, a mesophilic anaerobic sulfate-reducing bacterium known for its high proportions of alkylglycerol ether lipids in its membrane, under various cultivation conditions including temperature, pH, salinity, and ammonium and phosphorous concentrations. Employing an extensive analytical and computational lipidomic methodology, we identified an assemblage of nearly 400 distinct lipids, including a range of glycerol ether/ester lipids with various polar head groups. Information theory-based analysis revealed that temperature fluctuations and phosphate scarcity profoundly influenced the lipidome's composition, leading to an enhanced diversity and specificity of novel lipids. Notably, phosphorous limitation led to the biosynthesis of novel glucuronosylglycerols and sulfur-containing aminolipids, termed butyramide cysteine glycerols, featuring various ether/ester bonds. This suggests a novel adaptive strategy for anaerobic heterotrophs to thrive under phosphorus-depleted conditions, characterized by a diverse array of nitrogen-and sulfur-containing polar head groups, moving beyond a reliance on conventional nonphospholipid types. [ABSTRACT FROM AUTHOR]

Background: Lignin is a highly abundant but strongly underutilized natural resource that could serve as a sustainable feedstock for producing chemicals by microbial cell factories. Because of the heterogeneous nature of the lignin feedstocks, the biological upgrading of lignin relying on the metabolic routes of aerobic bacteria is currently considered as the most promising approach. However, the limited substrate range and the inefficient catabolism of the production hosts hinder the upgrading of lignin-related aromatics. Particularly, the aerobic O-demethylation of the methoxyl groups in aromatic substrates is energy-limited, inhibits growth, and results in carbon loss in the form of CO2. Results: In this study, we present a novel approach for carbon-wise utilization of lignin-related aromatics by the integration of anaerobic and aerobic metabolisms. In practice, we employed an acetogenic bacterium Acetobacterium woodii for anaerobic O-demethylation of aromatic compounds, which distinctively differs from the aerobic O-demethylation; in the process, the carbon from the methoxyl groups is fixed together with CO2 to form acetate, while the aromatic ring remains unchanged. These accessible end-metabolites were then utilized by an aerobic bacterium Acinetobacter baylyi ADP1. By utilizing this cocultivation approach, we demonstrated an upgrading of guaiacol, an abundant but inaccessible substrate to most microbes, into a plastic precursor muconate, with a nearly equimolar yields (0.9 mol/mol in a small-scale cultivation and 1.0 mol/mol in a one-pot bioreactor cultivation). The process required only a minor genetic engineering, namely a single gene knock-out. Noticeably, by employing a metabolic integration of the two bacteria, it was possible to produce biomass and muconate by utilizing only CO2 and guaiacol as carbon sources. Conclusions: By the novel approach, we were able to overcome the issues related to aerobic O-demethylation of methoxylated aromatic substrates and demonstrated carbon-wise conversion of lignin-related aromatics to products with yields unattainable by aerobic processes. This study highlights the power of synergistic integration of distinctive metabolic features of bacteria, thus unlocking new opportunities for harnessing microbial cocultures in upgrading challenging feedstocks. [ABSTRACT FROM AUTHOR]

Tuber magnatum is the most expensive truffle, but its large‐scale cultivation is still a challenge compared to other valuable Tuber species. T. magnatum mycelium has never been grown profitably until now, which has led to difficulties to studying it in vitro. This study describes beneficial interactions between T. magnatum mycelium and never before described bradyrhizobia, which allows the in vitro growth of T. magnatum mycelium. Three T. magnatum strains were co‐isolated on modified Woody Plant Medium (mWPM) with aerobic bacteria and characterised through microscopic observations. The difficulties of growing alone both partners, bacteria and T. magnatum mycelium, on mWPM demonstrated the reciprocal dependency. Three bacterial isolates for each T. magnatum strain were obtained and molecularly characterised by sequencing the 16S rRNA, glnII, recA and nifH genes. Phylogenetic analyses showed that all nine bacterial strains were distributed among five subclades included in a new monophyletic lineage belonging to the Bradyrhizobium genus within the Bradyrhizobium jicamae supergroup. The nifH genes were detected in all bacterial isolates, suggesting nitrogen‐fixing capacities. This is the first report of consistent T. magnatum mycelium growth in vitro conditions. It has important implications for the development of new technologies in white truffle cultivation and for further studies on T. magnatum biology and genetics. [ABSTRACT FROM AUTHOR]

Introduction: In chronic rhinosinusitis (CRS), the congestion and blockage of the nose can cause anaerobic conditions within the sinus cavities which may promote the expression of virulence and antibiotic resistance genes in invading pathogens. Pseudomonas aeruginosa is a facultative anaerobic bacteria and causes severe recalcitrant CRS. In this study, we aimed to evaluate the antimicrobial resistance of P. aeruginosa isolates of CRS patients in planktonic and biofilm form grown in aerobic and anaerobic conditions. Methods: P. aeruginosa clinical isolates of CRS patients (n = 25) were grown in planktonic and biofilm form in aerobic and anaerobic conditions. Minimum inhibitory concentrations (MIC) of planktonic forms and minimum biofilm eradication concentrations (MBEC) were determined. Additionally, metabolic activity by fluorescein diacetate assay, biofilm biomass by crystal violet assay and eDNA concentration were assessed in both conditions. Results: P. aeruginosa planktonic cells grown in anaerobic condition exhibited increased gentamicin resistance (p < .01), whereas P. aeruginosa biofilms grown in anaerobic condition displayed significantly increased MBEC values for gentamicin (p < .0001) and levofloxacin (p < .001). The metabolic activity of anaerobic biofilms was significantly higher compared with aerobic biofilms (p < .0001). However, the biofilm biomass of isolates grown in aerobic conditions was higher than anaerobic conditions (p < .5). Conclusion: P. aeruginosa isolates from CRS patients grown in anaerobic conditions showed significantly increased resistance to antibiotics with an increased metabolic activity but decreased biofilm biomass. [ABSTRACT FROM AUTHOR]

Objective: There are insufficient data in the literature concerning whether cellular changes in tissue are reflected in blood circulation in granulomatous infections, such as zoonotic brucellosis. In this study, we compared laboratory parameters between patients with brucella (BEO) and non-brucella epididymo-orchitis (NBEO). Materials and Methods: This retrospective study included 84 patients with BEO and 92 with NBEO who presented to six medical centers between 2017 and 2021. Results: The median age of the patients was 41 (interquartile range: 27-61) years. In the multivariate analysis, the presence of abdominal pain (p=0.003), the percentage of lymphocytes (p=0.012) and the percentage of monocytes (p=0.029) were significantly higher in the BEO group than in the NBEO group. In addition, the percentage of neutrophils (p=0.001) was significantly lower in the BEO group than in the NBEO group. In the receiver operating characteristic analysis, the percentage of lymphocytes had an area under the curve (AUC) value of 0.808 at a cut-off point of >22.1%, the percentage of monocytes had an AUC value of 0.745 at a cut-off point of >7.7%, and the percentage of neutrophils had an AUC value of 0.746 at a cut-off point of <66.8%. Conclusion: To the best of our knowledge, there is no other study comparing the percentages of lymphocytes, monocytes, and neutrophils between patients with BEO and NBEO. The percentages of mononuclear leukocytes (monocytes and lymphocytes) and neutrophils may be useful for the prediagnosis of BEO in endemic areas. [ABSTRACT FROM AUTHOR]

The relic Lake Mogilnoe, separated from the Barents Sea by a sand and pebble dam, is located in the high Arctic on the Kildin island (Murmansk region). This lake is a classic example of a meromictic basin of marine origin. The data obtained during the 2018 expedition showed changes in the hydrochemical regime of the lake that have occurred over the past 20 years. Sulfide concentration in the monimolimnion of the lake was as high as 140 mg/L. A tendency for salinization of the surface waters to 7 g/L has been noted. The Lake Mogilnoe is characterized by a discrepancy between the halocline and thermocline levels. The chemocline zone in the lake is below the halocline level. In a narrow oxygen-containing layer between 3 and 7.5 m, aerobic microflora of the marine type and marine fauna were present. The bacterial plate was formed at the boundary of the sulfide layer at ~8 m and mainly consisted of green sulfur bacteria (GSB). Brown-colored GSB species containing bacteriochlorophyll e were predominant. The previously formed concept of anaerobic phototrophic bacteria (APB) biodiversity based on morphological characteristics was modified using metagenomic data obtained by analyzing DNA from two samples of lake water in the chemocline zone, and was also supplemented by identifying new GSB species. Molecular diagnostic data confirmed the absolute dominance of the brackish species of GSB Chlorobium phaeovibrioides. This is the first isolation and identification of brown- and green-colored Prosthecochloris aestuarii morphotypes from Lake Mogilnoe, as well as of bacteriochlorophyll c-containing Prosthecochloris sp. The taxonomic position of Pelodyction phaem, which was constantly present in the Lake Mogilnoe, is discussed in detail. Despite the partial isolation of the ecosystem of Lake Mogilnoe from the Barents Sea, the main properties of the dominant GSB species and Prosthecochlori aestuarii turned out to be similar to those of the phylotypes living in lakes on the White Sea coast. [ABSTRACT FROM AUTHOR]

Background: Recent research has unveiled that approximately 50%-70% of patients afflicted with lung cancer also receive concurrent diagnoses of lung infections, most notably pneumonia. Among the critical multidrug- resistant pathogens frequently isolated from pneumonia-afflicted patients, Pseudomonas aeruginosa and Acinetobacter baumannii stand prominent. Here, we assessed the impact of antibiotics and vitamins on the lung cancer infection cell culture. Methods: The study delves into the antimicrobial properties of vitamins P, K, and E against A. baumannii and P. aeruginosa, employing the minimum inhibitory concentration method and scrutinizing biofilm formation within the A549 cell culture. Results: The combined application of vitamins and antibiotics exhibited a statistically significant effect on both the minimal inhibitory concentration values and biofilm formation (P < .05). Within the realm of fat-soluble vitamins, vitamins K and E, when integrated with antibiotics, revealed varying degrees of influence, with vitamin K displaying the most substantial fractional inhibitory concentration value. Vitamin E, on the other hand, demonstrated a comparatively weaker fractional inhibitory concentration than the other constituents. Nevertheless, it exhibited robust optical density and a pronounced capacity to inhibit biofilm formation. Moreover, among the vitamin groups, it is evident that vitamin E surpasses the efficacy of others (antibacterials affecting K < P < E). The collective application of all vitamins manifested the most potent fractional inhibitory concentration. Conclusion: The synergistic effects of vitamins with antibiotics, as evidenced in this study, may offer a promising alternative for treating multidrug-resistant A. baumannii and P. aeruginosa, subject to further investigation through molecular studies. [ABSTRACT FROM AUTHOR]

A patient presented with fever, severe pain and edematous tight due to hip trauma and was scheduled for urgent fasciotomy. Following physical examination, laboratory analyses were requested, and results revealed anemia and severe infection. As the patient's condition was serious, a new set of samples was sent to the laboratory four hours later. Following centrifugation, severely hemolyzed dark-colored serum and plasma samples were obtained and in vitro hemolysis was suspected. The collection of samples was repeated, but a new set of samples was also hemolyzed with a significant decrease in the hemoglobin value. At that point, in vivo hemolysis was suspected, and samples were processed according to standard laboratory procedures for hemolytic samples. Following confirmation of the gas gangrene diagnosis by clinicians, the cause of hemolysis was attributed to the cytotoxic activity of a-toxin produced by the anaerobic gram-positive bacterium Clostridium perfringens. An insight into the laboratory procedure that could help to narrow down the causes of hemolysis and single out C. perfringens as a cause of intravascular hemolysis was given. [ABSTRACT FROM AUTHOR]

Microorganisms are key players in the global biogeochemical sulfur cycle. Among them, some have garnered particular attention due to their electrical activity and ability to perform extracellular electron transfer. A growing body of research has highlighted their extensive phylogenetic and metabolic diversity, revealing their crucial roles in ecological processes. In this review, we delve into the electron transfer process between sulfate-reducing bacteria and anaerobic alkane-oxidizing archaea, which facilitates growth within syntrophic communities. Furthermore, we review the phenomenon of long-distance electron transfer and potential extracellular electron transfer in multicellular filamentous sulfur-oxidizing bacteria. These bacteria, with their vast application prospects and ecological significance, play a pivotal role in various ecological processes. Subsequently, we discuss the important role of the pili/cytochrome for electron transfer and presented cutting-edge approaches for exploring and studying electroactive microorganisms. This review provides a comprehensive overview of electroactive microorganisms participating in the biogeochemical sulfur cycle. By examining their electron transfer mechanisms, and the potential ecological and applied implications, we offer novel insights into microbial sulfur metabolism, thereby advancing applications in the development of sustainable bioelectronics materials and bioremediation technologies. [ABSTRACT FROM AUTHOR]

A novel aerotolerant anaerobic bacterium (strain M4AhT) was isolated from a terrestrial mud volcano (Taman Peninsula, Russia). Cells were small, cell-wall-less, non-motile cocci, 0.32–0.65 μm in diameter. The isolate was a mesophilic, neutrophilic chemoorganoheterotroph, growing on carbohydrates (D-glucose, D-trehalose, D-ribose, D-mannose, D-xylose, D-maltose, D-lactose, D-cellobiose, D-galactose, D-fructose, and D-sucrose), proteinaceous compounds (yeast extract, tryptone), and pyruvate. Strain M4AhT tolerated 2% oxygen in the gas phase, was catalase-positive, and showed sustainable growth under microaerobic conditions. The dominant cellular fatty acids of strain M4AhT were C16:0 and C18:0. The G+C content of the genomic DNA was 32.42%. The closest phylogenetic relative of strain M4AhT was Mariniplasma anaerobium from the family Acholeplasmataceae (order Acholeplasmatales, class Mollicutes). Based on the polyphasic characterization of the isolate, strain M4AhT is considered to represent a novel species of a new genus, for which the name Peloplasma aerotolerans gen. nov., sp. nov. is proposed. The type strain of Peloplasma aerotolerans is M4AhT (=DSM 112561T = VKM B-3485T = UQM 41475T). This is the first representative of the order Acholeplasmatales, isolated from a mud volcano. [ABSTRACT FROM AUTHOR]

Simple Summary: Various microorganisms, including Mycoplasma spp., have been reported in canine ejaculate. The impact of these microorganisms on semen quality remains unclear. The aim of this study was to evaluate the prevalence of bacteria and Mycoplasma spp. (and various species) in canine semen. Interestingly, 36.5% of the examined dogs tested negative for both aerobic bacteria and mycoplasmas, while 12.7% tested positive for bacterial presence. Additionally, 60.3% of the dogs tested positive for Mycoplasma spp. using PCR, with most carrying 1–2 Mycoplasma species. We found no significant difference in semen characteristics between Mycoplasma-positive and -negative dogs. The detection of Mycoplasma was not significantly linked to the presence of bacteria in semen. All the microorganisms identified were classified as saprophytic flora. Some canine ejaculate is sterile. Our findings suggest the existence of undescribed species of canine mycoplasmas, necessitating advanced diagnostic techniques like NGS for their identification. Various microorganisms, including Mycoplasma spp., have been reported in canine ejaculate. The impact of these microorganisms on semen quality remains unclear. This study included 63 male intact healthy dogs aged 1–8 years. One dog exhibited azoospermia, indicating a relatively low incidence of this condition. Interestingly, 36.5% of the examined dogs tested negative for both aerobic bacteria and mycoplasmas, while 12.7% tested positive for bacterial presence. Additionally, 60.3% of the dogs tested positive for Mycoplasma spp. using PCR, with most carrying 1–2 Mycoplasma species. We found no significant difference in semen characteristics between Mycoplasma-positive and -negative dogs. The detection of Mycoplasma was not significantly linked to the presence of bacteria in semen. All the microorganisms identified were classified as saprophytic flora. Our findings indicate that Mycoplasma spp. is common in canine ejaculate. Semen quality parameters were not correlated with the presence of Mycoplasma spp. in semen. Mycoplasma HRC689 was the most common species. Some dogs exhibited no presence of aerobic bacteria or mycoplasmas in their semen. Our study highlights the common presence of Mycoplasma spp. in canine ejaculate. Semen quality shows no correlation with Mycoplasma presence. Some canine ejaculate is sterile. Our findings suggest the existence of undescribed species of canine mycoplasmas, necessitating advanced diagnostic techniques like NGS for their identification. [ABSTRACT FROM AUTHOR]

Immunisation against preventable diseases as meningitis is crucial from a public health perspective to face challenges posed by these infections. Nurses hold a great responsibility for these programs, which highlights the importance of understanding their preferences and needs to improve the success of campaigns. This study aimed to investigate nurses' preferences regarding Meningococcus A, C, W, and Y (MenACWY) conjugate vaccines commercialised in Spain. A national-level discrete choice experiment (DCE) was conducted. A literature review and a focus group informed the DCE design. Six attributes were included: pharmaceutical form, coadministration evidence, shelf-life, package contents, single-doses per package, and package volume. Conditional logit models quantified preferences and relative importance (RI). Thirty experienced primary care nurses participated in this study. Evidence of coadministration with other vaccines was the most important attribute (RI = 43.78%), followed by package size (RI = 22.17%), pharmaceutical form (RI = 19.07%), and package content (RI = 11.80%). There was a preference for evidence of coadministration with routine vaccines (odds ratio [OR] = 2.579, 95% confidence interval [95%CI] = 2.210–3.002), smaller volumes (OR = 1.494, 95%CI = 1.264–1.767), liquid formulations (OR = 1.283, 95%CI = 1.108–1.486) and package contents including only vial/s (OR = 1.283, 95%CI = 1.108–1.486). No statistical evidence was found for the remaining attributes. Evidence of coadministration with routine vaccines, easy-to-store packages, and fully liquid formulations were drivers of nurses' preferences regarding MenACWY conjugate vaccines. These findings provide valuable insights for decision-makers to optimize current campaigns. [ABSTRACT FROM AUTHOR]

Introduction: Escherichia coli is a Gram negative, motile, facultative anaerobe and non-spore forming bacteria. Escherichia coli is belonging to the genus Escherichia and family Enterobacteriaceae. Escherichia coli account for the large majority of naturally acquired urinary tract infections (UTI). The present study aimed to determine the prevalence of Escherichia coli in urine samples at Dhiraj General Hospital. We also studied antibiotic susceptibility pattern of Escherichia coli isolated from urine and to correlate it with clinical condition of the patients. Materials and methods: The present study was conducted in Department of Microbiology, SBKS MI & RC, Dhiraj general Hospital, Waghodia for a period of April 2022 to July 2022. All the clinical specimens collected and transported to microbiology laboratory as per standard methods and was processed. Motile bacteria confirmed by Hanging drop preparation and on examination motile bacteria were seen. Identification and AST was done by VITEK 2 system. Data was collected and analyzed statistically. Results: During study period, a total 413 urine samples was collected and 264 (63.92%) samples were positive for bacterial growth out of them 72 (27.27%) urine sample were positive for Escherichia coli isolates. Out of 72 patients with Escherichia coli isolates, 47% isolate from male patients and 53% from female patients. In the present study, out of 72 Escherichia coli isolates, 67 were sensitive to Fosfomycin, 59 to Cefaperazone/salbactum and 109 were resistant to Ampicillin and Nalidixic acid, 62 to Ciprofloxacin. Conclusion: Escherichia coli is an important uropathogenic organism causing significant UTI. Resistance of antibiotics against bacteria increasing due to non systemic use in health care. We recommended a combined clinical and microbiological prevention strategies which include accurate investigation, invaluable input from the microbiological laboratory rational and early antibiotic therapy, timely surveillance, strict infection control measures, monitoring risk factors. [ABSTRACT FROM AUTHOR]

Tumor hypoxia plays a crucial role in driving cancer progression and fostering resistance to therapies by contributing significantly to chemoresistance, radioresistance, angiogenesis, invasiveness, metastasis, altered cell metabolism, and genomic instability. Despite the challenges encountered in therapeutically addressing tumor hypoxia with conventional drugs, a noteworthy alternative has emerged through the utilization of anaerobic oncolytic bacteria. These bacteria exhibit a preference for accumulating and proliferating within the hypoxic regions of tumors, where they can initiate robust antitumor effects and immune responses. Through simple genetic manipulation or sophisticated synthetic bioengineering, these bacteria can be further optimized to improve safety and antitumor activities, or they can be combined synergistically with chemotherapies, radiation, or other immunotherapies. In this review, we explore the potential benefits and challenges associated with this innovative anticancer approach, addressing issues related to clinical translation, particularly as several strains have progressed to clinical evaluation. [ABSTRACT FROM AUTHOR]

Udder cleft dermatitis (UCD) is a skin condition affecting the anterior parts of the udder in dairy cattle. In the present study, we aimed to shed light on the microbiota in severe UCD lesions versus healthy udder skin by putting forward a taxonomic and functional profile based on a virulence factor analysis. Through shotgun metagenomic sequencing, we found a high proportion of bacteria in addition to a low abundance of archaea. A distinct clustering of healthy udder skin versus UCD lesion samples was shown by applying principal component analysis and (sparse) partial least squares analysis on the metagenomic data. Proteobacteria , Bacillota , and Actinomycetota were among the most abundant phyla in healthy udder skin samples. In UCD samples, Bacteroidota was the most abundant phylum. At genus level, Bifidobacterium spp. had the highest relative abundance in healthy skin samples, whereas Porphyromonas spp. and Corynebacterium spp. had the highest relative abundance in UCD samples. In the differential abundance analysis, Porphyromonas spp. and Bacteroides spp. were significantly differentially abundant in UCD samples, whereas Bifidobacterium spp., Staphylococcus sp. AntiMn-1, and Staphylococcus equorum were more commonly found in healthy samples. Moreover, the abundance of several treponeme phylotypes was significantly higher in lesion samples. The streptococcal cysteine protease speB was among the most abundant virulence factors present in severe UCD lesions, while a plethora of virulence factors such as the antitoxin relB were downregulated, possibly contributing to creating the ideal wound climate for the dysbiotic community. Network analysis showed healthy lesion samples had a large network ofpositive, correlations between the abundances of beneficial species such as Aerococcus urinaeequi and Bifidobacterium angulatum , indicating that the healthy skin microbiome forms an active protective bacterial network, which is disrupted in case of UCD. In UCD samples, a smaller microbial network mainly consisting of positive correlations between the abundances of Bacteroides fragilis and anaerobic Bacteroidota was exposed. Moreover, a high correlation between the taxonomic data and virulence factors was revealed, concurrently with 2 separate networks of microbes and virulence factors. One network, matching with the taxonomic findings in the healthy udder skin samples, showcased a community of harmless or beneficial bacteria, such as Bifidobacterium spp. and Butyrivibrio proteoclasticus , associated with hcnB, hcnC, relB, glyoxalase, and cupin 2. The other network, corresponding to UCD samples, consisted of pathogenic or facultative pathogenic and mainly anaerobic bacteria such as Treponema spp., Mycoplasmopsis spp., and bovine gammaherpesvirus 4, that correlated with virulence factors SpvB, fhaB, and haemagglutination activity domain–associated factor. Our results point toward a dysbiotic community with a notable decrease in diversity and evenness, with a loss of normal skin inhabitants and innocuous or useful species making way for predominantly anaerobic, facultative pathogens. The shift in the abundance of virulence factors such as fhaB and SpvB could play a role in the manifestation of a local micro-environment favorable to the microbiome associated with udder skin lesions. Lastly, the presence of specific networks between microbial species, and between microbes and virulence factors was shown. [ABSTRACT FROM AUTHOR]

Hidradenitis Suppurativa (HS) is a chronic autoinflammatory skin disease with activated keratinocytes, tunnel formation and a complex immune infiltrate in tissue. The HS microbiome is polymicrobial with an abundance of commensal gram‐positive facultative (GPs) Staphylococcus species and gram‐negative anaerobic (GNA) bacteria like Prevotella, Fusobacterium and Porphyromonas with increasing predominance of GNAs with disease severity. We sought to define the keratinocyte response to bacteria commonly isolated from HS lesions to probe pathogenic relationships between HS and the microbiome. Type strains of Prevotella nigrescens, Prevotella melaninogenica, Prevotella intermedia, Prevotella asaccharolytica, Fusobacterium nucleatum, as well as Staphylococcus aureus and the normal skin commensal Staphylococcus epidermidis were heat‐killed and co‐incubated with normal human keratinocytes. RNA was collected and analysed using RNAseq and RT‐qPCR. The supernatant was collected from cell culture for protein quantification. Transcriptomic profiles between HS clinical samples and stimulated keratinocytes were compared. Co‐staining of patient HS frozen sections was used to localize bacteria in lesions. A mouse intradermal injection model was used to investigate early immune recruitment. TLR4 and JAK inhibitors were used to investigate mechanistic avenues of bacterial response inhibition. GNAs, especially F. nucleatum, stimulated vastly higher CXCL8, IL17C, CCL20, IL6, TNF and IL36γ transcription in normal skin keratinocytes than the GPs S. epidermidis and S. aureus. Using RNAseq, we found that F. nucleatum (and Prevotella) strongly induced the IL‐17 pathway in keratinocytes and overlapped with transcriptome profiles of HS patient clinical samples. Bacteria were juxtaposed to activated keratinocytes in vivo, and F. nucleatum strongly recruited murine neutrophil and macrophage migration. Both the TLR4 and pan‐JAK inhibitors reduced cytokine production. Detailed transcriptomic profiling of healthy skin keratinocytes exposed to GNAs prevalent in HS revealed a potent, extensive inflammatory response vastly stronger than GPs. GNAs stimulated HS‐relevant genes, including many genes in the IL‐17 response pathway, and were significantly associated with HS tissue transcriptomes. The close association of activated keratinocytes with bacteria in HS lesions and innate infiltration in murine skin cemented GNA pathogenic potential. These novel mechanistic insights could drive future targeted therapies. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the in vitro antibacterial effects of lysozyme‐chitosan oligosaccharide conjugates (LYZOX) against Streptococcus gordonii and Porphyromonas gingivalis. Materials and Methods: Planktonic S. gordonii and P. gingivalis were treated with various concentrations of LYZOX for 10 min. The treated bacteria were incubated on trypticase soy agar plates, and colony‐forming unit (CFU) was calculated. The antibacterial effect of LYZOX was compared with that of lysozyme, chitosan, physiological saline, and benzalkonium chloride solution. Cell morphology before and after LYZOX treatment was observed using a scanning electron microscope (SEM). The antibacterial effect of LYZOX with decanoic acid against the biofilm‐like bacteria was also examined via crystal violet staining. The Kruskal–Wallis test and post hoc Dunn tests were performed to compare the difference in antibacterial activity of each treatment. Results: Bacterial CFU numbers were reduced after LYZOX treatment in a concentration‐dependent manner. The reduction in CFUs was smaller for corresponding concentrations of chitosan or lysozyme alone. SEM analyses revealed bacterial cells shrank following LYZOX treatment. The combined use of LYZOX and decanoic acid yielded an even higher antibacterial effect against bacterial biofilms. Conclusion: LYZOX exhibits antibacterial activity against two periodontal bacteria and may be a promising plaque control agent. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to explore the potential role of zinc‐finger homeodomain transcription factor (TCF8) in osteoclastogenesis and inflammation during periodontitis. Materials and Methods: Rats with periodontitis were induced via Porphyromonas gingivalis‐lipopolysaccharide (Pg‐LPS) injection. The recombinant lentivirus delivering short hairpin RNA (shRNA) against TCF8 was used to downregulate TCF8 in vivo. Alveolar bone loss in rats was determined by micro‐computed tomography (Micro‐CT). Typical pathological changes, periodontal tissue inflammation, and osteoclastogenesis were evaluated via histological analyses. The RAW264.7‐derived osteoclasts were induced by RANKL stimulation. TCF8 downregulation in vitro was achieved by lentivirus infection. The osteoclast differentiation and inflammatory signaling in RANKL‐induced cells were measured via immunofluorescence methods and molecular biology approaches. Results: Porphyromonas gingivalis‐lipopolysaccharide induced rats exhibited overexpressed TCF8 in their periodontal tissues, while TCF8 knockdown attenuated the bone loss, tissue inflammation, and osteoclastogenesis in LPS‐induced rats. Besides, TCF8 silencing inhibited RANKL‐induced osteoclast differentiation in RAW264.7 cells, as evidenced by the reduced numbers of TRAP‐positive osteoclasts, less formation of F‐actin rings, and downregulated expressions of osteoclast‐specific markers. It also exerted an inhibitory effect on the NF‐κB signaling in RANKL‐induced cells via blocking NF‐κB p65 phosphorylation and nuclear translocation. Conclusions: TCF8 silencing inhibited alveolar bone loss, osteoclast differentiation, and inflammation in periodontitis. [ABSTRACT FROM AUTHOR]

Background: The causal relationship between breast cancer (BC) and the oral microbiome remains unclear. In this case–control study, using two‐sample Mendelian randomization (MR), we thoroughly explored the relationship between the oral microbiome and BC in the East Asian population. Methods: Genetic summary data related to oral microbiota and BC were collected from genome‐wide association studies involving participants of East Asian descent. MR estimates were generated by conducting various analyses. Sequencing data from a case–control study were used to verify the validity of these findings. Results: MR analysis revealed that 30 tongue and 37 salivary bacterial species were significantly associated with BC. Interestingly, in both tongue and salivary microbiomes, we observed the causal effect of six genera, namely, Aggregatibacter, Streptococcus, Prevotella, Haemophilus, Lachnospiraceae, Oribacterium, and Solobacterium, on BC. Our case–control study findings suggest differences in specific bacteria between patients with BC and healthy controls. Moreover, sequencing data confirmed the MR analysis results, demonstrating that compared with the healthy control group, the BC group had a higher relative abundance of Pasteurellaceae and Streptococcaceae but a lower relative abundance of Bacteroidaceae. Conclusions: Our MR analysis suggests that the oral microbiome exerts a causative effect on BC risk, supported by the sequencing data of a case–control study. In the future, studies should be undertaken to comprehensively understand the complex interaction mechanisms between the oral microbiota and BC. [ABSTRACT FROM AUTHOR]

We consider the Cauchy problem for the Keller-Segel system of consumption type coupled with the incompressible Euler equations in R 2. This coupled system describes a biological phenomenon in which aerobic bacteria living in slightly viscous fluids (such as water) move towards a higher oxygen concentration to survive. We firstly prove the local existence of smooth solutions for arbitrary smooth initial data. Then we show that these smooth solutions can be extended globally if the initial density of oxygen is sufficiently small. The main ingredient in the proof is the W 1 , q -energy estimate (q > 2) motivated by the partially inviscid two-dimensional Boussinesq system. Our result improves the well-known global well-posedness of the two-dimensional Keller-Segel system of consumption type coupled with the incompressible Navier-Stokes equations. [ABSTRACT FROM AUTHOR]

In freshwater habitats, aerobic animals and microorganisms can react to oxygen deprivation by a series of behavioural and physiological changes, either as a direct consequence of hindered performance or as adaptive responses towards hypoxic conditions. Since oxygen availability can vary throughout the water column, different strategies exist to avoid hypoxia, including that of active 'flight' from low‐oxygen sites. Alternatively, some organisms may invest in slower movement, saving energy until conditions return to more favourable levels, which may be described as a 'sit‐and‐wait' strategy. Here, we aimed to determine which, if any, of these strategies could be used by the freshwater ciliate Tetrahymena thermophila when faced with decreasing levels of oxygen availability in the culture medium. We manipulated oxygen flux into clonal cultures of six strains (i.e. genotypes) and followed their growth kinetics for several weeks using automated image analysis, allowing to precisely quantify changes in density, morphology and movement patterns. Oxygen effects on demography and morphology were comparable across strains: reducing oxygen flux decreased the growth rate and maximal density of experimental cultures, while greatly expanding the duration of their stationary phase. Cells sampled during their exponential growth phase were larger and had a more elongated shape under hypoxic conditions, likely mirroring a shift in resource investment towards individual development rather than frequent divisions. In addition to these general patterns, we found evidence for intraspecific variability in movement responses to oxygen limitation. Some strains showed a reduction in swimming speed, potentially associated with a 'sit‐and‐wait' strategy; however, the frequent alteration of movement paths towards more linear trajectories also suggests the existence of an inducible 'flight response' in this species. Considering the inherent costs of turns associated with non‐linear movement, such a strategy may allow ciliates to escape suboptimal environments at a low energetic cost. [ABSTRACT FROM AUTHOR]

Background Revised diagnostic criteria for infective endocarditis (IE), the 2023 Duke-ISCVID criteria, were recently presented and need validation. Here, we compare the 2000 modified Duke criteria for IE with Duke-ISCVID among patients with bacteremia and relate the diagnostic classification to IE treatment. Methods We reanalyzed patient cohorts with Staphylococcus aureus , Staphylococcus lugdunensis , non–β-hemolytic streptococci, Streptococcus -like bacteria, Streptococcus dysgalactiae, Enterococcus faecalis, and HACEK (Haemophilus , Aggregatibacter , Cardiobacterium , Eikenella , Kingella) bacteremia. Episodes were classified as definite, possible, or rejected IE with the modified Duke and Duke-ISCVID criteria. Reclassification included the microbiology criteria, positron emission tomography–computed tomography, and cardiac implanted electronic devices. To calculate sensitivity, patients treated for IE were considered as having IE. Results In 4050 episodes of bacteremia, the modified Duke criteria assigned 307 episodes (7.6%) as definite IE, 1190 (29%) as possible IE, and 2553 (63%) as rejected IE. Using the Duke-ISCVID criteria, 13 episodes (0.3%) were reclassified from possible to definite IE, and 475 episodes (12%) were reclassified from rejected to possible IE. With the modified Duke criteria, 79 episodes that were treated as IE were classified as possible IE, and 11 of these episodes were reclassified to definite IE with Duke-ISCVID. Applying the decision to treat for IE as a reference standard, the sensitivity of the Duke-ISCVID criteria was 80%. None of the 475 episodes reclassified to possible IE were treated as IE. Conclusions The Duke-ISCVID criteria reclassified a small proportion of episodes to definite IE at the expense of more episodes of possible IE. Future criteria should minimize the possible IE group while keeping or improving sensitivity. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a neurological condition that is much more common as people get older. It may start out early or late. Increased levels of pro-inflammatory cytokines and microglial activation, both of which contribute to the central nervous system's inflammatory state, are characteristics of AD. As opposed to this, periodontitis is a widespread oral infection brought on by Gram-negative anaerobic bacteria. By releasing pro-inflammatory cytokines into the systemic circulation, periodontitis can be classified as a "low-grade systemic disease." Periodontitis and AD are linked by inflammation, which is recognized to play a crucial part in both the disease processes. The current review sought to highlight the effects of pro-inflammatory cytokines, which are released during periodontal and Alzheimer's diseases in the pathophysiology of both conditions. It also addresses the puzzling relationship between AD and periodontitis, highlighting the etiology and potential ramifications. [ABSTRACT FROM AUTHOR]

The relationship among gut microbiota, mitochondrial dysfunction/neuroinflammation, and diabetic neuropathic pain (DNP) has received increased attention. Ginger has antidiabetic and analgesic effects because of its anti-inflammatory property. We examined the effects of gingerols-enriched ginger (GEG) supplementation on pain-associated behaviors, gut microbiome composition, and mitochondrial function and neuroinflammation of colon and spinal cord in DNP rats. Thirty-three male rats were randomly divided into 3 groups: control group, DNP group (high-fat diet plus single dose of streptozotocin at 35 mg/kg body weight, and GEG group (DNP+GEG at 0.75% in the diet for 8 weeks). Von Frey and open field tests were used to assess pain sensitivity and anxio-depressive behaviors, respectively. Colon and spinal cord were collected for gene expression analysis. 16S rRNA gene sequencing was done from cecal samples and microbiome data analysis was performed using QIIME 2. GEG supplementation mitigated mechanical hypersensitivity and anxio-depressive behavior in DNP animals. GEG supplementation suppressed the dynamin-related protein 1 protein expression (colon) and gene expression (spinal cord), astrocytic marker GFAP gene expression (colon and spinal cord), and tumor necrosis factor-α gene expression (colon, P <.05; spinal cord, P =.0974) in DNP rats. GEG supplementation increased microglia/macrophage marker CD11b gene expression in colon and spinal cord of DNP rats. GEG treatment increased abundance of Acinetobacter, Azospirillum, Colidextribacter , and Fournierella but decreased abundance of Muribaculum intestinale in cecal feces of rats. This study demonstrates that GEG supplementation decreased pain, anxio-depression, and neuroimmune cells, and improved the composition of gut microbiomes and mitochondrial function in rats with diabetic neuropathy. GEG supplementation mitigated pain-associated behaviors, favored gut microbiome composition, and improved mitochondrial function in HFD + STZ rats. Abbreviations: GEG, gingerol-enriched ginger; HFD+STZ, high-fat diet and streptozocin. [Display omitted] [ABSTRACT FROM AUTHOR]

In recent years, ultraviolet and ultrasound treatments are gaining attraction as promising green decontamination technologies to ensure microbial safety in food industry. Decontamination by ultraviolet light is a physical process defined by the transfer of electromagnetic energy from a light source to an organism's cellular material and depended on the emission of radiation in the ultraviolet region (100–400 nm), specifically the UV-C region (200–280 nm) which has been demonstrated to be germicidal. Ultrasound technology is defined as sound waves with high and low frequency beyond the limit of human hearing and shows a decontamination effect that occurs as a consequence of cavitation at high power (low frequency) in general. In the present study, it was aimed to determine the effectiveness of ultraviolet light (254 nm, 10 min) and high frequency ultrasound techniques (40 kHz, 10 min) in reducing total aerobic mesophilic bacteria, yeast and mold, Esherichia coli /coliform and Salmonella spp. on the equipment surfaces used in the catering facility. For this purpose, the equipment (cutting knife, meat grinder knife, knife sharpener, cut-proof glove) used in the meat preparation department of catering facility were selected for the treatments. According to the results, appreciable reductions were achieved in total aerobic mesophilic bacterial counts of the ultraviolet treated samples (maximum difference 2.61 log cfu/cm2) and the ultrasound treated samples (maximum difference 4.07 log cfu/cm2). After ultraviolet treatment, Salmonella spp. were totally inhibited on the contaminated surfaces. Furthermore, Escherichia coli /coliform was not detected in the samples after both treatments whereas it was detected before the treatments. It has been concluded that the techniques are effective in reducing microbiological load and also ultraviolet treatment is effective on pathogenic microorganisms on food contact surfaces. As a result, the ultraviolet and ultrasound techniques are effective treatments for equipment disinfection in the catering sector and can be used industrially as it gives successful results. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of hop extracts on changes in the primary and secondary fat oxidation products, physicochemical properties, and microbiological quality of pâté-type offal sausages obtained through the partial replacement of animal fat with vegetable fat. This study demonstrated that the extraction efficiency varied among hop cone varieties, with the highest efficiency observed for the Lubelski variety and the lowest for the Magnum variety. The phenolic compound content was higher in the Magnum cones (2.74 ± 0.11 mg/g dry matter) compared to the Lubelska cones (2.27 ± 0.05 mg/g of product). Additionally, the DPPH radical scavenging activity was greater in the extract from the Magnum cones (4.21 ± 0.09 mg TE/g d.w.) than in the extract from the Lublelski cones (3.87 ± 0.05 mg TE/ g d.w.). Similarly, the extracts from the Lubelski cones exhibited a higher antiradical activity against the ABTS radical compared to the extract from Magnum cones. Throughout storage, a significant increase in the pH value was observed in the control sample and in the samples with a 20% replacement of animal fat with rapeseed oil and Magnum hop extract. However, the addition of Lubelski hop extract resulted in a decrease in the pH value during the 15-day storage period. The samples with a 20% replacement of animal fat with rapeseed oil and 0.1% Lubelski hop extract showed the least changes in water activity during storage. The samples with a 20% replacement of animal fat with rapeseed oil and the addition of 0.2% Lubelski hop extract had the lowest peroxide value and TBARS index throughout the storage period. The addition of hop extract inhibited the growth of the total number of microorganisms in the tested sausages. In the samples with a 20% replacement of animal fat with rapeseed oil, the content of aerobic microorganisms, compared to the control sample, was statistically significantly lower. [ABSTRACT FROM AUTHOR]

Background: A notable improvement in the treatment of necrotizing soft tissue infections (NSTIs) is the development of negative pressure wound therapy (NPWT). Clinicians are still debating whether NPWT is as successful as conventional wet-to-dry dressings at removing bacteria. Recent research has revealed potential oxygen deprivation effects of NPWT in underlying wound tissues, although clinical trials regarding the effects of reduced oxygen on anaerobic bacterial soft tissue infections remain noticeably lacking. Hypothesis: We hypothesized that NPWT-treated patients with NSTIs who were solely infected by anaerobic bacteria would have worse outcomes than those who were infected with other bacterial species. Patients and Methods: Our study included a retrospective examination of the 2008–2022 period of our Acute and Critical Care Surgery database. Patients who had been identified as having necrotizing fasciitis, Fournier gangrene, or gas gangrene and who had their conditions verified by positive wound cultures acquired during the initial debridement and subsequently received NPWT made up the study cohort. Comorbidities, surgical techniques, and clinical results were all covered by the data. Based on their wound infections, patients were divided into two groups: those with exclusively anaerobic NSTIs and those with different bacterial groups (such as polymicrobial and aerobic). Multiple regression, χ2 analysis, and analysis of variance (ANOVA) were among the analytical methods used. Results: One hundred twelve patients with NSTI who had received NPWT comprised the study cohort. Sixteen of these patients (14.3%) had NSTIs that were exclusively anaerobic, whereas the remaining 96 (85.7%) had NSTIs that were mixed aerobic, facultative, or polymicrobial. Between the two groups, there was no difference in the initial wound size. Patients with anaerobic NSTI who underwent NPWT showed a statistically significant increase in the number of debridements (3 [interquartile range {IQR},1–9] vs. 2 [IQR, 1–4]; p = 0.012) and an increased 100-day re-admission rate (37.5% vs. 12.5%; p = 0.012) when compared with patients with non-anaerobic NSTI. The 100-day re-admission rate increased three-fold in NPWT-treated anaerobic NSTIs, according to a logistic regression analysis (odds ratio [OR], 3.63; 95% confidence interval [CI], 1.06–12.44; p = 0.04). Conclusions: In contrast to patients with other bacterial strains, our data show that patients with NSTI treated with NPWT who only have anaerobic bacterial infections have a larger number of debridements and are much more likely to require re-admission within 100 days. We call for additional prospective studies to be conducted to identify additional risk factors and consider alternate treatment options for individuals with exclusively anaerobic NSTIs in light of these findings. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of high-pressure microfluidization on the physicochemical attributes, antioxidant, enzymatic, and microbiological activity of ginger rhizome (Zingiber officinale Roscoe) juice at different microfluidization pressures (68.94, 103.42, and 137.89 MPa) and cycles (1, 2, and 3). An important physical attribute, the mean particle size of ginger rhizome juice, was significantly (p < 0.05) decreased from 15.85 (control) to 12.86 µm at 137.89 MPa and 1 cycle, which was further supported by microscopic inspection revealing cell disintegration. Due to the release of phenolic compounds and pigments brought on by cell disruption, total phenolic content, antioxidant activity assay DPPH, and ABTS values increased from 56.79 to 65.28 mg GAE/100 mL, 69.99 to 77.51% inhibition, and 74.61 to 84.74% inhibition, respectively, at 103.42 MPa and 3 cycles. The polyphenol oxidase (PPO) enzyme was shown to be baroresistant because microfluidization had no noticeable impact on its relative activity. A higher microfluidization pressure of 137.89 MPa resulted in the complete reduction of aerobic bacteria, yeast, and molds. Due to its solvent-free nature and success in microbial reduction, microfluidization may aid in the delivery of high quality clean-labeled ginger juice. The findings demonstrated that microfluidization treatment has the potential to produce clean-labeled, safe ginger juice with improved overall quality. This study provides useful information to industries for the commercialization of ginger juice and will assist in promoting the usage of undervalued rhizome species. [ABSTRACT FROM AUTHOR]

Bacteriological studies of well water mainly focus on aerobic and facultative aerobic coliform bacteria. However, the presence of obligate anaerobic bacteria in well water, especially sulfate-reducing bacteria (SRB), possible causative agents of some diseases, is often ignored. In this study, the presence of SRB and coexisting anaerobic bacteria with SRB in sulfate-reducing enrichment cultures obtained from 10 well water samples in Istanbul was investigated. A nested polymerase chain reaction-denaturing gradient gel electrophoresis strategy was performed to characterize the bacterial community structure of the enrichments. The most probable number method was used to determine SRB number. Out of 10, SRB growth was observed in only one (10%) enrichment culture and the SRB number was low (,10 cells/mL). Community members were identified as Desulfolutivibrio sulfodismutans and Anaerosinus sp. The results show that SRB coexist with Anaerosinus sp., and this may indicate poor water quality, posing a risk to public health. Furthermore, Anaerosinus sp., found in the human intestinal tract, may be used as an alternative anaerobic fecal indicator. It is worth noting that the detection of bacteria using molecular analyzes following enrichment culture techniques can bring new perspectives to determine the possible origin and presence of alternative microbial indicators in aquatic environments. [ABSTRACT FROM AUTHOR]

Background: Diabetic foot ulcer (DFU) is a major complication of diabetes mellitus (DM) which is associated with high morbidity and mortality. There is high rate of bacteria colonization especially in those with tendencies for poor wound dressing. This is accompanied by high rate of inappropriate antibiotic usage. The aim of this study is to characterize microbial pathogens colonizing foot ulcers of diabetic patients in Enugu, Nigeria, and to determine the antibiotic susceptibility of these isolates. Methodology: This was a descriptive cross-sectional study of consecutively enrolled diabetic patients with foot ulcers in two tertiary healthcare facilities in Enugu, Nigeria, between May 2021 and February 2022. A structured questionnaire was used to obtain socio-demographic and clinical data of the patients. Pus samples and/or tissues were collected from the ulcer lesion of each patient for aerobic and anaerobic microbial cultures and biochemical identification using standard conventional techniques. Results: A total of 310 diabetic patients with foot ulcers were recruited into the study, with 62.3% (193/310) males and 37.7% (117/310) females, and mean age of 56.0±13.9 years. Bacteria and yeast were isolated from samples of 280 (90.3%) patients while samples of 30 (9.7%) patients had no microbial growth. Males had higher frequency of microbial isolates (90.7%, 175/193) than females (89.7%, 105/117), while the age group ≤ 40 years had higher frequency of microbial isolates (100%, 43/43) compared to other age groups, although the differences are not statistically significant (p>0.05). The distribution of the isolates showed that 15.7% (44/280) were monomicrobial while 84.3% (236/280) were polymicrobial. The highest single isolate was Bacteroides fragilis with 5.0% (14/280), followed by Staphylococcus aureus with 3.2% (9/280). Bacteroides fragilis and S. aureus occurred as the highest combined bacteria isolates with 5.7% (16/280). Most of the patients were colonized by combination of bacterial isolates. The susceptibility indicates that most of the anaerobic bacteria were sensitive to metronidazole while S. aureus isolates were resistant to ofloxacin at a rate of 65.0%. Conclusion: The findings in this study showed that there is high bacteria and fungi colonization of foot ulcers of diabetic patients in Enugu, Nigeria. Routine care of wounds especially frequent changes of dressing materials and the use of potent antiseptics, are recommended. [ABSTRACT FROM AUTHOR]

Aim: We sought to investigate the release of neutrophil extracellular traps (NETs) in neutrophils from individuals with rheumatoid arthritis (RA) and controls and compare the presence of NETs in gingival tissues according to periodontal status. Also, the association between single nucleotide polymorphisms (SNPs) of the peptidyl arginine deaminase type 4 (PADI4) gene and the GTG haplotype with RA, periodontitis and NETs was evaluated in vitro. Materials and Methods: Peripheral neutrophils were isolated by density gradient, and NET concentration was determined by the PicoGreen method. Immunofluorescence was studied to identify NETs by co‐localization of myeloperoxidase (MPO)‐citrullinated histone H3 (H3Cit). Genotyping for SNPs (PADI4_89; PADI4_90; PADI4_92; and PADI4_104) was performed in 87 individuals with RA and 111 controls. Results: The release of NETs in vitro was significantly higher in individuals with RA and periodontitis and when stimulated with Porphyromonas gingivalis. Gingival tissues from subjects with RA and periodontitis revealed increased numbers of MPO‐H3Cit‐positive cells. Individuals with the GTG haplotype showed a higher release of NETs in vitro and worse periodontal parameters. Conclusions: The release of NETs by circulating neutrophils is associated with RA and periodontitis and is influenced by the presence of the GTG haplotype. [ABSTRACT FROM AUTHOR]

Aim and background: Myroides (M.) species are ubiquitous in the environment and cause a variety of infections like urinary tract infections (UTI), sepsis, meningitis, cholecystitis, pneumonia, and soft tissue infections, especially among immunocompromised populations. These are usually resistant to multiple antibiotics. This study aimed to demonstrate the clinical profile, underlying comorbidities, and antimicrobial susceptibility of Myroides isolates obtained from nosocomial UTI cases. Materials and methods: A sudden rise in the isolation of Myroides spp. from the repeated urine samples of admitted patients alerted us to conduct this retrospective observational study. Urine cultures that grew M. species were included in this study. Antibiotic susceptibility was performed and the patient's clinical data was analyzed. Results: A total of 14 Myroides spp. isolates were obtained from urine culture. The maximum number of cases (71.4%) were from the Nephrology ward and ICUs. The average (mean) age of patients was 46 years (range 2-80 years). All patients were catheterized. All isolates were multidrug resistant. Minocycline and doxycycline were the only drugs found effective in this study. Conclusions: Myroides species are emerging rare pathogens that can cause UTI in immunocompromised and catheterized patients. Minocycline may be used for treating such infections. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) are probiotic bacteria that have many health benefits. The aim of study was to determinate LAB from traditional cheeses (Gedebey, Ivanovka, Karabakh) consumed in Azerbaijan. The microbial content and loading of three traditional samples were explored using counting methods and a culture-independent approach. The average count of total bacteria in both of samples ranged between 105 and 107 cfu/g. In all samples, aerobic bacteria and lactic acid bacteria were more >4.9 × 105 cfu/g. The V3-V4 region of 16S rDNA was amplified from total DNA extracted from traditional cheese samples and microbial communities and lactic acid bacteria were determined. In general, the diversity of microbial populations in cheese samples were Lactobacillus, Lactococcus, Streptococcus. Among the three samples, Gedebey sample showed the highest richness. Obtained data can be use in the food industry. In addition, lactic acid bacteria analysis could help the determination of potential strains for traditional cheese production. In conclusion, determination and identification of LAB strains in traditional cheeses will reveal the traditional food microbiota and will help to find potential probiotic bacteria for health and industry. [ABSTRACT FROM AUTHOR]

In freshwater habitats, aerobic animals and microorganisms can react to oxygen deprivation by a series of behavioural and physiological changes, either as a direct consequence of hindered performance or as adaptive responses towards hypoxic conditions. Since oxygen availability can vary throughout the water column, different strategies exist to avoid hypoxia, including that of active 'flight' from low‐oxygen sites. Alternatively, some organisms may invest in slower movement, saving energy until conditions return to more favourable levels, which may be described as a 'sit‐and‐wait' strategy. Here, we aimed to determine which, if any, of these strategies could be used by the freshwater ciliate Tetrahymena thermophila when faced with decreasing levels of oxygen availability in the culture medium. We manipulated oxygen flux into clonal cultures of six strains (i.e. genotypes) and followed their growth kinetics for several weeks using automated image analysis, allowing to precisely quantify changes in density, morphology and movement patterns. Oxygen effects on demography and morphology were comparable across strains: reducing oxygen flux decreased the growth rate and maximal density of experimental cultures, while greatly expanding the duration of their stationary phase. Cells sampled during their exponential growth phase were larger and had a more elongated shape under hypoxic conditions, likely mirroring a shift in resource investment towards individual development rather than frequent divisions. In addition to these general patterns, we found evidence for intraspecific variability in movement responses to oxygen limitation. Some strains showed a reduction in swimming speed, potentially associated with a 'sit‐and‐wait' strategy; however, the frequent alteration of movement paths towards more linear trajectories also suggests the existence of an inducible 'flight response' in this species. Considering the inherent costs of turns associated with non‐linear movement, such a strategy may allow ciliates to escape suboptimal environments at a low energetic cost. [ABSTRACT FROM AUTHOR]

Hospital infections associated with uncommon pathogens usually originated from environmental sources and are challenging for microbiologists and clinicians because of the difficulties in the differentiation of colonization vs infection. Increasing reports of bacteremia caused by environmental pathogens point out their importance in hospital infections. The increasing number of case reports of bacteremia due to Cupriavidus spp., impose to consider these unusual microorganisms which are aerobic Gram-negative rods that live in soil and water. In this report, we present two cases of bacteremia in which Cupriavidus metallidurans were isolated from blood cultures and discuss the roles of the isolates in hospital infection. [ABSTRACT FROM AUTHOR]

Coating crayfish (Astacus leptodactylus) meat samples with chitosan solution could be an effective approach to limit microbiological spoilage. During the 18-day cold storage period at 2°C±1, mesophilic aerobic bacteria (MABc), psychrophilic bacteria (PBc), yeast mold count (YMc), anaerobic bacteria (AnBc), and Enterobacteriaceae growth in the samples coated with chitosan (0.5% and 1%) and also control group samples were tested. Crayfish samples coated with chitosan (0.5% and 1%) had a lower TMABc (6.58 to 4.60 log CFU/g: up to 30.09%), TPBc (3.77 to 1.99 log CFU/g: up to 47.21%), TYMc (1.84 to 1.27 log CFU/g: up to 30.97%), TAnBc (3.69 to 1.88 log CFU/g: up to 49.05%), and Enterobacteriaceae (3.49 to 2.60 log CFU/g: up to 25.50%) counts as compared with control group samples at 2°C±1. The results particularly based on mesophilic anaerobic bacteria suggested that the application would be a promising approach to limit microbial growth and provide food safety for boiled crayfish meat samples. [ABSTRACT FROM AUTHOR]

Morganella morganii is a gram negative, facultative anaerobic rod‐shaped bacterium, commonly found in environment and in the intestine of human, mammals, and reptiles as a part of their gut microbiome. M. morganii can cause Gram‐negative folliculitis, black nail infection, acute retiform purpura, fetal demise, and subdural empyema. The increasing frequency of M. morganii infections generate the need for efficient methods to enrich the presence of M. morganii in clinical samples to make its detection easier. Culturomics aims to grow and maximize the number of culturable bacteria. Different methods are followed to maximize the growth of minority population of bacteria by disrupting the growth of bacteria which are present in higher concentration. This article presents a method for selective enriching the M. morganii in human fecal samples. This method includes prior incubation of fecal microbiota in an anaerobic environment, adding supplement like fecal water to give dormant bacteria a break to become active to grow to threshold concentration, and an enrichment stage which provides the additional opportunity of growing to M. morganii on the selective medium. This method also provides an ingenuous way for augmenting the growth of fecal M. morganii species. Significance statement: Morganella morganii can cause Gram‐negative folliculitis, black nail infection, acute retiform purpura, fetal demise, and subdural empyema. The increasing frequency of M. morganii infections generate the need for efficient methods to enrich the presence of M. morganii in clinical samples to make its detection easier. Different methods are followed to maximize the growth of a minority population of bacteria by disrupting the growth of bacteria which are present in higher concentration. Our research work developed a method which includes prior incubation of fecal microbiota in an anaerobic environment, adding supplement like fecal water to give dormant bacteria a break to become active to grow to threshold concentration, and an enrichment stage which provides the additional opportunity of growing to M. morganii on the selective medium. [ABSTRACT FROM AUTHOR]

Carbapenemase‐producing gram‐negative bacteria (CP‐GNB) infections threaten public health with high mortality, morbidity and treatment costs. Although frequencies remain low in Australia (total number of CP‐GNB infections reported was 907 in 2022), blaIMP‐4 has established low levels of endemicity in many states. Imipenemase metallo‐β‐lactamase types alone accounted for more than half of all carbapenemases in carbapenemase‐producing Enterobacterales isolates in Australia, particularly in Enterobacter cloacae complex. New Delhi metallo‐β‐lactamase constitutes almost 25% of all carbapenemases in Australia and was identified predominantly in Escherichia coli. The OXA‐48‐like carbapenemases include almost 10% of all carbapenemases and are mainly seen in Klebsiella pneumoniae and E. coli. Although K. pneumoniae carbapenemase‐type carbapenemases are rare in Australia, some local outbreaks have occurred. Most carbapenem‐resistant (CR) Pseudomonas aeruginosa strains in Australia do not produce carbapenemases. Finally, OXA‐23‐like carbapenemases are overwhelmingly positive in CR‐Acinetobacter baumannii strains in Australia. Treatment of CR‐GNB infections challenges physicians. Of 10 new antibiotics active against at least some CR‐GNB infections that are approved by the US Food and Drug Administration, just three are approved for use in Australia. In this context, there is still an unmet need for novel antibacterials that can be used for the treatment of CR‐GNB infections in Australia, as well as a pressing requirement for new mechanisms to 'de‐link' antibiotic sales from their availability. In this narrative review, we aim to overview the epidemiology and clinical significance of carbapenem resistance in Australia as it pertains to Enterobacterales, P. aeruginosa and A. baumannii. [ABSTRACT FROM AUTHOR]

Background: Nocardia is a ubiquitous saprophyte capable of causing human disease. Disease is primarily respiratory or cutaneous, usually acquired via inhalation or inoculation. Under the influence of environmental and host factors, Nocardia incidence and species distribution demonstrate geographical variation. Aims: To examine for differences in Nocardia incidence within Western Australia (WA) and analyse species distribution in the context of prior published studies. To analyse antibiogram data from a nationwide passive antimicrobial resistance surveillance program. Methods: Retrospective extraction of laboratory data for Western Australian Nocardia isolates over a 21‐year period. Analysis of Nocardia antimicrobial susceptibility testing data submitted to the Australian Passive Antimicrobial Resistance Surveillance (APAS) program between 2005 and 2022. Results: Nine hundred sixty WA isolates were identified, giving an annual incidence of 3.03 per 100 000 population with apparent latitudinal variation. The four most common species identified within WA and amongst APAS isolates were N. nova, N. cyriacigeorgica, N. brasiliensis and N. farcinica. APAS data demonstrated that all species exhibited high rates of susceptibility to linezolid (100%) and trimethoprim‐sulfamethoxazole (98%). Amikacin (>90% susceptibility for all species except N. transvalensis) was the next most active parenteral agent, superior to both carbapenems and third‐generation cephalosporins. Susceptibility to oral antimicrobials (other than linezolid) demonstrated significant interspecies variation. Conclusions: We demonstrate geographical variation in the distribution of Nocardia incidence. Four species predominate in the Australian setting, and nationwide data confirm a high in vitro susceptibility to trimethoprim‐sulphamethoxazole and linezolid, justifying their ongoing role as part of first‐line empiric therapy. [ABSTRACT FROM AUTHOR]

This experiment aimed to assess the effects of ultrasound techniques on the quality of Iranian industrial honey. Honey samples were subjected to ultrasound waves at different frequencies and various parameters. The results showed that both ultrasound treatments (30 or 42 kHz) changed the physical, biochemical, antioxidant, and antibacterial characteristics of honey. Ultrasound treatments at 20 or 45°C for 1, 5, or 10 min reduced moisture, acidity, sugars, ABTS levels, 5‐hydroxymethylfurfural content, clostridium, aerobic mesophilic bacteria count, and osmophile count while increasing diastase, phenol, and proline levels. Ultrasound treatment of honey samples at 30 and 42 kHz and different temperatures for varying durations led to a decrease in acidity after 90 and 180 days. Treating honey samples with 42 kHz ultrasound at 45°C for 10 min led to a significant reduction in the amount of reducing sugar. Ultrasonication at different frequencies and temperatures led to higher levels of phenol, ABTS, and proline production, along with a considerable decrease in the total count of aerobic mesophilic bacteria. Our study unveils the potential of ultrasonication to enhance honey quality through multifaceted improvements. Treatment significantly augmented phenolic content and antioxidant capacity, opening avenues for novel honey preservation and quality enhancement strategies. Additionally, ultrasonication effectively controlled honey crystallization while simultaneously improving biochemical, antioxidant, and antibacterial properties. This demonstrates its potential as a comprehensive strategy for honey quality improvement. [ABSTRACT FROM AUTHOR]

Aerobic anoxygenic phototrophic (AAP) bacteria harvest light energy using bacteriochlorophyll-containing reaction centers to supplement their mostly heterotrophic metabolism. While their abundance and growth have been intensively studied in coastal environments, much less is known about their activity in oligotrophic open ocean regions. Therefore, we combined in situ sampling in the North Pacific Subtropical Gyre, north of O'ahu island, Hawaii, with two manipulation experiments. Infra-red epifluorescence microscopy documented that AAP bacteria represented approximately 2% of total bacteria in the euphotic zone with the maximum abundance in the upper 50 m. They conducted active photosynthetic electron transport with maximum rates up to 50 electrons per reaction center per second. The in situ decline of bacteriochlorophyll concentration over the daylight period, an estimate of loss rates due to predation, indicated that the AAP bacteria in the upper 50 m of the water column turned over at rates of 0.75-0.90 d-1. This corresponded well with the specific growth rate determined in dilution experiments where AAP bacteria grew at a rate 1.05 ± 0.09 d-1. An amendment of inorganic nitrogen to obtain N:P = 32 resulted in a more than 10 times increase in AAP abundance over 6 days. The presented data document that AAP bacteria are an active part of the bacterioplankton community in the oligotrophic North Pacific Subtropical Gyre and that their growth was mostly controlled by nitrogen availability and grazing pressure. IMPORTANCE Marine bacteria represent a complex assembly of species with different physiology, metabolism, and substrate preferences. We focus on a specific functional group of marine bacteria called aerobic anoxygenic phototrophs. These photoheterotrophic organisms require organic carbon substrates for growth, but they can also supplement their metabolic needs with light energy captured by bacteriochlorophyll. These bacteria have been intensively studied in coastal regions, but rather less is known about their distribution, growth, and mortality in the oligotrophic open ocean. Therefore, we conducted a suite of measurements in the North Pacific Subtropical Gyre to determine the distribution of these organisms in the water column and their growth and mortality rates. A nutrient amendment experiment showed that aerobic anoxygenic phototrophs were limited by inorganic nitrogen. Despite this, they grew more rapidly than average heterotrophic bacteria, but their growth was balanced by intense grazing pressure. [ABSTRACT FROM AUTHOR]

This study aimed to optimize minimal thermal treatment conditions for sour cherry juice using response surface methodology. The effects of ultrasound power (UP; 54, 35, 14 W), ultrasound time (UT; 8, 5, 3 min), ohmic electrical field strength (OE; 40, 30, 20 V/cm) and ohmic time (OT; 8, 5, 3 min) on total phenolic content (TPC), antioxidant activity (AA), color values (L*, a*, b*, ΔE), total monomeric anthocyanin content (TMAC), polymeric color (PC), color density (CD), polymeric color ratio (PC%), total mesophilic aerobic bacteria (TMAB) and yeast-mold count (YM) were investigated. UP significantly affected TPC, L*, a*, b*, and ΔE, while OE affected TPC, TMAC, PC, PC%, and TYC. UT affected TPC, L*, AA, CD, PC and PC%, and OT level affected TPC and b* values. The optimum points were determined by considering maximum TPC as 28.7564, maximum AA as 6.7714, maximum TMAC as 4.9616, maximum L* as 21.3839, maximum a* as 5.5396, maximum b* as 3.4260, maximum color density as 27.1412, minimum polymeric color as 17.3148, minimum PC% as 4.9253, minimum TYC as 1.9251 and minimum TMBC as 2.3301. The optimum levels were found to be 54 W, 8 min, 27.06 V/cm and 8 min. Improvements in TPC, TMAC and AA were determined after ultrasound-ohmic combination thermal treatment. Although ohmic (OH) has the effect of maintaining juice quality, its effectiveness is impacted by the electrochemical properties of food. By using ultrasound, the electrical conductivity values of juices were increased; thus, ultrasound improved the electrochemical properties of sour cherry juice. Further studies are needed to evaluate the effects of ultrasound-ohmic combination for juice processing on a large scale. [ABSTRACT FROM AUTHOR]