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Introduction: Organic meat products are well known for their probiotic values due to the presence of probiotic lactic acid bacteria such as Lactobacillus, Leuconostoc, Lactococcus, and Pediococcus strains. The present study aimed to isolate and characterize new strains of lactic acid bacteria (LABs) from organic meat sausages and evaluate their antimicrobial activities. Materials and Methods: In this study, LAB strains were isolated from vacuum-packed organic meat sausages bought from Solico Group Co Ltd. (Tehran, Iran). All isolates were characterized by morphological, biochemical, and 16S rRNA analysis. The primary antibacterial activity of the isolates was evaluated against Micrococcus luteus PTCC 1408. The growth kinetics and antimicrobial activity of the strain MN-B against Lactobacillus casei ATCC 39392 were determined in an MRS broth medium. In addition, a bacteriocin produced by the strains MN-B revealed antimicrobial activity against selected foodborne pathogens. Bacteriocin produced by the MN-B strain was partially purified using the adsorption-desorption method followed by dialyzes. Results: In this study, two Pediococcus spp. and three Leuconostoc spp. with antimicrobial activity were isolated from vacuum-packed organic meat sausages and designated as MNA, MN-B, MN-A2, MN-A2-1, and MN-A3. The results showed that the isolate MN-A and MN-B belonged to the strain Pediococcus acidilactici and the MN-A2, MN-A2-1, and MN-A3 isolates were identified as Leuconostoc mesenteroides strains. Amongst the isolates, the strain MN-B showed the highest antimicrobial activity against the Micrococcus luteus PTCC 1408. The molecular weight of bacteriocin was about 5.0 KDa. Discussion and Conclusion: Pediococcus acidilactici (strain MN-B) showed significant antimicrobial activity against Salmonella enterica subsp. enterica serotype Typhimurium PTCC 1709, Staphylococcus aureus PTCC 1113, Listeria monocytogenes PTCC1302, and Listeria inovani PTCC 1303. Therefore, this strain can be considered a potential candidate in different sectors such as the food industry as a preservative. [ABSTRACT FROM AUTHOR]

The aim of this work was to provide an overview of available information on the antibacterial and antifungal properties of Epilobium angustifolium extracts. A literature search of Scopus, PubMed/Medline, and Google Scholar for peer-reviewed articles published between January 2000 and June 2023 was undertaken. A total of 23 studies were eligible for inclusion in this review. Significant variation of antimicrobial activity depending on the tested species and strains, type of extract solvent, or plant organs utilized for the extract preparation was found. E. angustifolium extracts were active against both Gram-positive and Gram-negative bacteria and showed antimycotic effects against the fungi of Microsporum canis and Trichophyton tonsurans and the dermatophytes Arthroderma spp. Greater susceptibility of Gram-positive than Gram-negative bacteria to fireweed extracts was found. A strong antibacterial effect was recorded for Staphylococcus aureus, Bacillus cereus, Micrococcus luteus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii including multi-drug resistant strains. E. angustifolium extract might find practical application as an antimicrobial in wound healing, components of cosmetic products for human and animals, or as food preservatives. [ABSTRACT FROM AUTHOR]

Aerosols in caves are natural tracers and, together with climatic parameters, provide a detailed insight into atmospheric conditions, responses to climatic changes and anthropogenic influences in caves. Microbiological air monitoring in show caves is becoming increasingly useful to understand changes in cave ecosystems and to implement and review measures for sustainable cave use and tourism development. In 2017 and 2018, air along tourist trails in caves Postojnska jama and Škocjanske jame (Slovenia) was sampled before and after tourist visits. Samples were analysed using culture-dependent methods, flow cytometry, detection of β-D-glucan and lipopolysaccharide and compared with CO2 and temperature data to measure anthropogenic influences and seasonality on aerobiota. While the presence of tourists significantly increased concentrations of airborne microorganisms (p < 0.05), β-D-glucan and CO2 did not show such a trend and were more dependent on seasonal changes. Locally, concentrations of cultivable microorganisms above 1000 CFU/m3 were detected, which could have negative effects on the autochthonous microbiota and possibly on human health. A mixture of bacteria typically associated with humans was found in the air and identified with MALDI-TOF MS. Using MALDI-TOF MS, we achieved a 69.6% success rate in identification. Micrococcus luteus, Streptococcus mitis, Staphylococcus epidermidis and Moraxella spp. were recognized as good indicators of cave anthropisation. [ABSTRACT FROM AUTHOR]

Exopolysaccharides (EPS) are acknowledged for their diverse functional and technological properties. This study presents the characterization of EPS400, an acidic exopolysaccharide sourced from the native probiotic Limosilactobacillus fermentum NCDC400. Notably, this strain has demonstrated previous capabilities in enhancing dairy food texture and displaying in vivo hypocholesterolemic activity. Our investigation aimed to unveil EPS400′s potential biological roles, encompassing antioxidant, antibacterial, and immunomodulatory activities. The results underscore EPS400′s prowess in scavenging radicals, including the 2,2-diphenyl-1-picrylhydrazyl radical, 2,2′-azino-di-(3-ethylbenzthiazoline sulfonic acid) radical, superoxide radical, hydroxyl radical, and chelating activity targeting the ferrous ion. Furthermore, EPS400 displayed substantial antibacterial effectiveness against prevalent food spoilage bacteria such as Pseudomonas aeruginosa NCDC105 and Micrococcus luteus. Remarkably, EPS400 exhibited the ability to modulate cytokine production, downregulating pro-inflammatory cytokines TNF-α, IL-1β, IL-6, and nitric oxide, while concurrently promoting the release of anti-inflammatory cytokine IL-10 within lipopolysaccharide-activated murine primary macrophages. Additionally, EPS400 significantly (p ≤ 0.05) enhanced the phagocytic potential of macrophages. Collectively, our findings spotlight EPS400 as a promising contender endowed with significant antioxidant, antibacterial, and immunomodulatory attributes. These characteristics propose EPS400 as a potential pharmaceutical or bioactive component, with potential applications in the realm of functional food development. [ABSTRACT FROM AUTHOR]

We studied the physicochemical and electrochemical characteristics of microbial fuel cells (MFCs) with a new proton-exchange membrane. It was synthesized on the basis of zeolite-doped polyvinyl alcohol cross-linked with sulfosuccinic acid (PVA-SSA-BEA). An MF-4SK industrial membrane (Plastpolymer, Russia) was used as a comparative sample. Various sugars were added as substrates (glucose, arabinose, galactose, xylose). The role of the bioagent was performed by the strain Micrococcus luteus 1-i. MFCs with PVA‑SSA-BEA and MF-4SK membranes showed rather close electrochemical characteristics. A higher electricity output was performed with the addition of glucose, galactose, the lowest—with the use of xylose. The data obtained indicate that the proposed PVA-SSA-BEA membrane is promising for use as an alternative to proton-exchange membranes widely used in fuel cell technology. [ABSTRACT FROM AUTHOR]

This paper is aimed to synthesize and characterize lysozyme-modified microengines for the degradation of bacteria. For this purpose, Pt/reduced graphene oxide (rGO) microengines were synthesized and modified covalently with lysozyme enzyme. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy analysis (EDX) techniques were used for the characterization. The pH, temperature and substrate concentration-dependent activities of lysozyme-modified microengines were investigated and compared with the free lysozyme. In addition, the high thermal and storage stability of lysozyme-modified microengines has been demonstrated. Lysozyme-modified microengines degraded 100% of Micrococcus lysodeikticus within 5 min. Bacterial degradation was photographed under the microscope, and the movement of microengines carrying lysozyme with bubble was also videoed. Microengines functionalized with lysozyme prepared in this study can potentially be used to destroy bacteria in environmental applications. [ABSTRACT FROM AUTHOR]

Simple Summary: In recent decades, more and more data have been accumulated on the close interaction of the human microbiota with the human organism. Today, we can safely say that human hormones are microbiota regulators that can influence both the behavior of individual species and the balance of microbial communities. However, the mechanisms of such action have been elucidated for an extremely small number of microorganisms. In particular, very little is known about how hormones, especially catecholamines, affect skin Gram-positive microorganisms and their biofilms. In our work, we studied for the first time how epinephrine at a concentration close to normal in blood plasma affects the protein composition of planktonic cultures and biofilms of the skin microorganism Micrococcus luteus C01, as well as how the protein composition changes depending on the cultivation time. It was shown that despite the small number of genes with altered expression in the presence of the hormone, the concentration of dozens and hundreds of proteins changes in the presence of epinephrine. The main "targets" of epinephrine are proteins of ribosomes, the tricarboxylic acid cycle, and cell division. Thus, this study opens up great prospects for further work in the field of microbial endocrinology. In the current study, extensive Orbitrap mass spectrometry analysis was conducted for skin strain Micrococcus luteus C01 planktonic cultures and biofilms after 24 h and 72 h of incubation either in the presence of epinephrine or without any implementations. The investigation revealed the complex and conditionally extensive effect of epinephrine at concentrations closer to normal blood plasma concentrations on both planktonic cultures and biofilms of skin strain M. luteus C01. The concentrations of hundreds of proteins changed during the shift from planktonic growth mode to biofilm and hundreds of proteins were downregulated or upregulated in the presence of epinephrine. Ribosomal, TCA, and cell division proteins appear to be the most altered in their amounts in the presence of the hormone. Potentially, the regulatory mechanism of this process is connected with c-di-GMP and histidine kinases, which were affected by epinephrine in different samples. The phenomenon of epinephrine-based biofilm regulation in M. luteus C01 has wide implications for microbial endocrinology and other research areas. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Universally, in microbiological diagnostics the detection of live bacteria is essential. Rapid identification of pathogens enables appropriate remedial measures to be taken. The identification of many bacteria simultaneously facilitates the determination of the characteristics of the accompanying microbiota and/or the microbiological complexity of a given environment. The effectiveness of the VITEK2 Compact automated microbial identification system and matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF MS), analytical profile index (API) and Remel RapID tests were compared in identification of bacteria isolated from the alpaca gastrointestinal tract. Most isolates were Gram-positive, such as Bacillus cereus, Bacillus flexus, Bacillus licheniformis, Bacillus pumilus and Bacillus subtilis; Enterococcus faecium, Enterococcus gallinarum, Enterococcus hirae and Enterococcus casseliflavus; Staphylococcus aureus, Staphylococcus equorum, Staphylococcus lentus, Staphylococcus pseudintermedius and Staphylococcus sciuri; Paenibacillus amylolyticus; Cellulosimicrobium cellulans; Leuconostoc mesenteroides; Clostridium perfringens; Corynebacterium stationis, Corynebacterium xerosis, and Corynebacterium diphtheriae (the last only isolated manually by API Coryne and the VITEK2 system and Corynebacteria (CBC) card). Corynebacterium diphtheriae was misidentified by MALDI-TOF MS as Candida lipolytica (currently Yarrowia lipolytica). Gram-positive and Gram-variable Micrococcus luteus were also isolated. Gram-negative Enterobacter cloacae, Enterobacter gergoviae, Enterobacter hormaechei and Enterobacter ludwigii; E. coli; Klebsiella pneumoniae subsp. pneumoniae; Citrobacter braakii and Citrobacter freundii; Serratia liquefaciens, Serratia odorifera and Serratia marcescens; Morganella morganii subsp. morganii; Providencia alcalifaciens; Pseudomonas aeruginosa; Stenotrophomonas maltophilia; Moraxella osloensis; and Ochrobactrum intermedium were also found. The yeasts Candida albicans, Candida haemulonii and Candida ciferrii were also present. MALDI-TOF MS enabled the identification of pathogens and opportunistic pathogens from the alpaca gut which may represent a high risk to human and animal health. [ABSTRACT FROM AUTHOR]

This study examined the chemical composition and anti-coccal properties of essential oils and methanolic extracts of six different Humulus lupulus L. varieties from Poland: Iunga, Marynka, Sybilla, Magnum, Tradition and Chinook. The activity of an α-acid-enriched fraction of methanolic extracts was also studied. The chemical composition of essential oils and extracts was determined by gas chromatography–mass spectrometry (GC/MS) and liquid chromatography–mass spectrometry (LC/MS) techniques. The compounds characteristic to H. lupulus extracts include xanthohumol, α-acids, β-acids, and prenylated flavonoids. Essential oil compositions showed a high prevalence of monoterpene hydrocarbon, myrcene and sesquiterpene hydrocarbons, α-humulene and β-caryophyllene. The antimicrobial activity was investigated against eight human cocci pathogenic strains: Staphylococcus aureus MRSA (ATCC 43300), S. aureus MRSA (29213), S. aureus MSSA (ATCC 29213), S. epidermidis (ATCC 12228), Enterococcus faecalis (ATCC 29212), E. faecalis VRE (ATCC 51299), E. faecium (ATCC 19434) and Micrococcus luteus (ATCC 10240). The lowest minimum inhibitory concentrations (MIC) were obtained for extracts and essential oils from Iunga hop samples. Extracts were significantly more active than essential oils. The most susceptible strain to both essential oils and extracts was M. luteus, whilst the least susceptible was E. faecium. The antimicrobial activity correlated with a high concentration of xanthohumol of active extracts rather than with the content of α-acids. Xanthohumol showed considerable activity against MRSA with an MIC value of 3.9 µg/mL. The activity of the α-acid-enriched fraction was mediocre compared to the results of all extracts. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the roots of Allophylus spicatus (Sapindacea) led to the isolation of four compounds, namely cleomiscosin A (1), cleomiscosin C (2), scopoletin (3) and 3-oxotirucalla-7,24-dien-24-oic acid (4). The structures of the compounds were established by spectroscopic analysis: UV, IR, 1D and 2D NMR, EI-MS and HR-EI-MS and compared with the literature. These compounds are reported for the first time from the plant. The compounds showed potent antibacterial activity, marked inhibition against most of the tested bacterial strains: Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), Salmonella typhi (ATCC 25923), Klebsiella pneumonia (ATCC 13883), Streptococcus faecalis (ATCC 29212) and Micrococcus luteus (ATCC 10240), with a zone of inhibition between 0.7±0.35 - 16±0.46 mm as compared with the zone of inhibition of Streptomycin (20±0.34 - 31±0.29 mm), a known antibacterial drug used as the standard. The antibacterial activity of the isolated phytochemicals could be responsible for the plant ethno-medicinal uses. [ABSTRACT FROM AUTHOR]

The antimicrobial activity of several extracts and fractions of Salvia verbenaca L. (Lamiaceae) was investigated by disc diffusion and broth microdilution methods against Escherichia coli ATCC 10536, Staphylococcus aureus ATCC 6538P, Klebsiella pneumoniae UC57, Micrococcus luteus La 2971, Micrococcus flavus ATCC 14452, Proteus vulgaris ATCC 8427, Pseudomonas aeruginosa ATCC 27853, Listeria monocytogenes ATCC 19115, Mycobacterium smegmatis CCM 2067, Bacillus cereus ATCC 7064, Bacillus subtilis ATCC 6633, Candida albicans ATCC 10231, Cryptococcus neoformans ATCC 90112, Kluyveromyces fragilis NRRL 2415 and Rhodotorula rubra DSM 70403. The methanol extract, butanol and chloroform fractions have shown potential antimicrobial effects against some bacteria and the yeast cultures tested, with grown inhibition area diameters in the range 10.8 – 22.4 mm, and MIC values between 0.03 and 0.34 µL/mL. The results of the study support the use of the plant in traditional medicine. [ABSTRACT FROM AUTHOR]

Antisepsis of the hands of medical personnel is one of the most important steps in the process of patient care, since direct contact can cause the cross-transfer of potentially pathogenic microorganisms at surgical sites. This study aimed to analyze the prevalence of microorganisms on the hands of 131 surgeons in a university hospital before the surgical procedure. Swabs were collected from each clinician's hands before and after handwashing. The samples were placed in a transport medium and immediately delivered to a private clinical analysis laboratory from São Luis-Maranhão. The microorganisms were identified by ionization source mass spectrometry and matrix-assisted laser desorption (MALDI-TOF), and antibiotic susceptibility tests (AST) were performed using the Vitek2 and Phoenix-BD automated system. The results showed a high frequency (100%) of microorganisms before handwashing, but after surgical antisepsis, the rate dropped significantly (p < 0.05) to 27.5%. The gram-positive species most detected were Staphylococcus spp. and Micrococcus luteus, representing 83.9%, followed by gram-negative species, Stenotrophomonas maltophilia, Acinetobacter baumanii, Pseudomonas aeruginosa, Pseudomonas gessardi, Pantoea septica, Serratia marcescens, and Burkholderia lata. The effectiveness of hand antisepsis was 72.5%, demonstrating that surgeons' hands are an important source of microorganisms that can cause infections in hospitalized patients in different care settings. [ABSTRACT FROM AUTHOR]

Bacterial contamination of semen has become an important contributor to the reduced shelf life of insemination doses in the poultry industry, which is why antibiotics (ATBs) are an important component of semen extenders. Due to a global rise in antimicrobial resistance, the aim of this study was to assess the efficiency of selected commercially available semen extenders to prevent possible bacterial contamination of rooster ejaculates. Two selected extenders free from or containing 31.2 µg/mL kanamycin (KAN) were used to process semen samples from 63 healthy Lohmann Brown roosters. Phosphate-buffered saline without ATBs was used as a control. The extended samples were stored at 4 °C for 24 h. Sperm motility, viability, mitochondrial activity, DNA integrity and the oxidative profile of each extended sample were assessed following 2 h and 24 h of storage. Furthermore, selective media were used to quantify the bacterial load and specific bacterial species were identified with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The results indicate that semen extenders enriched with KAN ensured a significantly higher preservation of sperm quality in comparison to their KAN-free counterparts. Bacterial load was significantly decreased in diluents supplemented with ATBs (p ≤ 0.001); however, KAN alone was not effective enough to eradicate all bacteria since several Escherichia coli, Enterococcus faecalis, Enterococcus faecium and Micrococcus luteus were retrieved from samples extended in KAN-supplemented commercial extenders. As such, we may suggest that more focus should be devoted to the selection of an optimal combination and dose of antibiotics for poultry extenders, which should be accompanied by a more frequent bacteriological screening of native as well as extended poultry semen. [ABSTRACT FROM AUTHOR]

3, 5, 6-Trichloro-2-pyridinol (TCP) is a metabolite of the insecticide chlorpyrifos and the herbicide triclopyr, and it is higher toxic than the parent compounds. Microbially-mediated mineralization appears to be the primary degradative pathway and the important biological process of detoxification. However, little information is available on TCP complete metabolic pathways and mechanisms. In this study, the degradation of TCP was studied with a novel strain Micrococcus luteus ML isolated from a stable TCP degrading microbiota. Strain ML was capable of degrading 61.6% of TCP (50 mg/L) and 35.4% of chlorpyrifos (50 mg/L) at 24 h and 48 h under the optimal conditions (temperature: 35 °C; pH: 7.0), respectively. It could also degrade 3, 5-dichloro-2-pyridone, 6-chloropyridin-2-ol, 2-hydroxypyridine and phoxim when provided as sole carbon and energy sources. Seven TCP intermediate metabolites were detected in strain ML and two possible degradation pathways of TCP were proposed on the basis of LC–MS analysis. Both the hydrolytic-oxidative dechlorination pathway and the denitrification pathway might be involved in TCP biodegradation by strain ML. To the best of our knowledge, this is the first report on two different pathways responsible for TCP degradation in one strain, and this finding also provides novel information for studying the metabolic mechanism of TCP in pure culture. [ABSTRACT FROM AUTHOR]

Luria–Bertani broth (LB) culture medium is a commonly used bacterial culture medium in the laboratory. The nutrient composition, concentration, and culture conditions of LB medium can influence the growth of microbial strains. The purpose of this article is to demonstrate the impact of LB liquid culture medium on microbial growth under different sterilization conditions. In this study, LB medium with four different treatments was used, as follows: A, LB medium without treatments; B, LB medium with filtration; C, LB medium with autoclaving; and D, LB medium with autoclaving and cultured for 12 h. Subsequently, the protein levels and antioxidant capacity of the medium with different treatments were measured, and the effects of the different LB medium treatments on the growth of microorganisms and metabolites were determined via 16s rRNA gene sequencing and metabolomics analysis, respectively. Firmicutes and Lactobacillus were the dominant microorganisms, which were enriched in fermentation and chemoheterotrophy. The protein levels and antioxidant capacity of the LB medium with different treatments were different, and with the increasing concentration of medium, the protein levels were gradually increased, while the antioxidant capacity was decreased firstly and then increased. The growth trend of Bacillus subtilis, Bacillus paralicheniformis, Micrococcus luteus, and Alternaria alternata in the medium with different treatments was similar. Additionally, 220 and 114 differential metabolites were found between B and C medium, and between C and D medium, which were significantly enriched in the "Hedgehog signaling pathway", "biosynthesis of plant secondary metabolites", "ABC transporters", "arginine and proline metabolism", and "linoleic acid metabolism". LB medium may be a good energy source for Lactobacillus growth with unsterilized medium, and LB medium filtered with a 0.22 μm filter membrane may be used for bacterial culture better than culture medium after high-pressure sterilization. LB medium still has the ability for antioxidation and to keep bacteria growth whether or not autoclaved, indicating that there are some substances that can resist a high temperature and pressure and still maintain their functions. [ABSTRACT FROM AUTHOR]

Infectious pathogens can be transmitted through textiles. Therefore, additional efforts are needed to develop functional fabrics containing antimicrobial substances to prevent the growth of antibiotic-resistant bacteria and their biofilms. Here, we developed a cotton fabric coated with reduced graphene oxide (rGO) and copper nanoparticles (Cu NPs), which possessed hydrophobic, antimicrobial, and anti-biofilm properties. Once the graphene oxide was dip-coated on a cellulose cotton fabric, Cu NPs were synthesized using a chemical reduction method to fabricate an rGO/Cu fabric, which was analyzed through FE-SEM, EDS, and ICP-MS. The results of our colony-forming unit assays indicated that the rGO/Cu fabric possessed high antibacterial and anti-biofilm properties against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, Corynebacterium xerosis, and Micrococcus luteus. Particularly, the fabric could inhibit the growth of E. coli, C. xerosis, and M. luteus with a 99% efficiency. Furthermore, our findings confirmed that the same concentrations of rGO/Cu had no cytotoxic effects against CCD-986Sk and Human Dermal Fibroblast (HDF), human skin cells, and NIH/3T3, a mouse skin cell. The developed rGO/Cu fabric thus exhibited promising applicability as a cotton material that can maintain hygienic conditions by preventing the propagation of various bacteria and sufficiently suppressing biofilm formation while also being harmless to the human body. [ABSTRACT FROM AUTHOR]

A series of novel Mannich bases were designed, synthesized, and screened for their antimicrobial activity. The target compounds were synthesized from 4-(3-chlorophenyl)-5-(3-fluorophenyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione and different piperazine derivatives. The structures of the products were confirmed by 1H and 13C NMR and elemental analysis. The activity of piperazine derivatives against bacteria (Gram-positive: Staphylococcus epidermidis, Staphylococcus aureus, Micrococcus luteus, Bacillus cereus, and Bacillus subtilis; Gram-negative: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Proteus mirabilis) and yeasts (Candida glabrata, Candida krusei, and Candida parapsilosis) was determined by the minimum inhibitory concentration and minimum bactericidal concentration values. Significant activity was observed against Gram-positive bacteria, mainly staphylococci (PG7–PG8) and bacteria of the genes of Micrococcus and Bacillus (PG1-3), as well as selected strains of Gram-negative bacteria, including bacteria of the Enterobacteriaceae family (PG7), while all tested compounds showed high fungistatic activity against Candida spp. yeasts, especially C. parapsilosis, with MICs ranging from 0.49 µg/mL (PG7) to 0.98 µg/mL (PG8) and 62.5 µg/mL (PG1-3). In conclusion, the results obtained confirm the multidirectional antimicrobial activity of the newly synthesized piperazine derivatives. Furthermore, in silico studies suggest that the tested compounds are likely to have good oral bioavailability. The results obtained will provide valuable data for further research into this interesting group of compounds. The library of compounds obtained is still the subject of pharmacological research aimed at finding new interesting biologically active compounds. [ABSTRACT FROM AUTHOR]

The aim of the study was to search for, isolate and characterize new bacteriolytic enzymes that show promising potential for their use in medicine, agriculture and veterinary. Using a transcriptomic analysis, we annotated in Lysobacter capsici VKM B-2533T the genes of known bacteriolytic and antifungal enzymes, as well as of antibiotics, whose expression levels increased when cultivated on media conducive to the production of antimicrobial agents. The genes of the secreted putative bacteriolytic proteases were also annotated. Two new bacteriolytic proteases, Serp and Serp3, were isolated and characterized. The maximum bacteriolytic activities of Serp and Serp3 were exhibited at low ionic strength of 10 mM Tris-HCl, and high temperatures of, respectively, 80 °C and 70 °C. The pH optimum for Serp was 8.0; for Serp3, it was slightly acidic, at 6.0. Both enzymes hydrolyzed autoclaved cells of Micrococcus luteus Ac-2230T, Proteus vulgaris H-19, Pseudomonas aeruginosa and Staphylococcus aureus 209P. Serp also digested cells of Bacillus cereus 217. Both enzymes hydrolyzed casein and azofibrin. The newly discovered enzymes are promising for developing proteolytic antimicrobial drugs on their basis. [ABSTRACT FROM AUTHOR]

A novel Schiff base has been synthesized from the condensation of the 3‐formyl‐2‐hydroxybenzoic acid and 4‐nitrobenzene‐1,2‐diamine. The new ligand was found to have two coordination sites. So, it has the capability to form mono‐ and binuclear complexes with different metal ions. The free ligand and its mono‐ and binuclear cobalt(II) complexes have been characterized by UV–Visible spectra, IR, elemental analyzes, H1 NMR, conductimetric, thermal, and magnetic measurements. Results indicated that the cobalt(II) ion is attached to the inside coordination site and the second metal ion attached to the outside coordination site. The complexes are all non‐electrolytes, as demonstrated by the molar conductance tests. The thermodynamic parameters of the metal complexes are calculated using Horowitz Metzger and Coats‐Redfern methods. The complexes' bonding properties have also been estimated. Molecular docking was employed to forecast the interaction of the prepared with the Candida‐albicans receptor (1zap). The biological activities of these metal complexes were tested against some bacteria and fungi. It is evident from the biological screening data that the prepared Co(II) binuclear complexes exhibit predominant activity against Candida albicans, Penicillium oxalicum and Escherichia coli, while they have no activity against Micrococcus roseus and Micrococcus luteus. [ABSTRACT FROM AUTHOR]

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Comprehensive Summary: Lobophorins (LOBs) belong to a large family of spirotetronate antibiotics with antibacterial and antitumor activities. In this study, we demonstrated the function of LobP1, a P450 monooxygenase encoded in the LOB biosynthetic gene cluster, by in vivo deletion and in vitro biochemical assays. The disruption of lobP1 led to the isolation of three new LOBs derivatives (3—5) and three known ones (6—8) without the hydroxyl group at C‐32. LobP1 was shown to have relatively broad substrate scope. Determining the kinetic parameters of LobP1 towards different substrates revealed that LobP1 preferred substrate with a nitrosugar. The new LOBs 3—5 displayed significant antibacterial activities against Bacillus subtilis and Micrococcus luteus with MIC values of 0.125 to 1 μg·mL–1, and the major product LOB E (6) from the ∆lobP1 mutant showed moderate cytotoxic activities against several cancer cell lines. [ABSTRACT FROM AUTHOR]

In the present study, the role of the skin microbiota in regulating skin homeostasis and protecting against the harmful effects of the sun is examined. The active ingredient PhotobiomeTM protects the microorganisms involved in skin photoprotection and has been confirmed through in vitro and in vivo studies. Various microorganisms of the skin microbiota, such as Staphylococcus epidermidis, Micrococcus luteus, Bifidobacterium spp., and Malassezia furfur, contribute to protecting the skin from sun exposure. The active ingredient PhotobiomeTM derived from Punica granatum and Gossypium herbaceum stem cells is used to prevent photoaging and repair light-induced skin damage. Clinical studies have shown that the application of the active ingredient increases skin firmness, reduces pigmentation spots, and diminishes wrinkles. The active ingredient PhotobiomeTM has been tested in a clinical study and has proven to be effective in reducing wrinkles and improving skin firmness and elasticity. [Extracted from the article]

Propolis (bee glue), a valuable biological mixture produced by European honey bees (Apis mellifera L.), is widely used as a remedy in traditional and alternative medicine, as an effective food biopreservative and as a nutritional value enhancer. The present study aimed to investigate eighty propolis samples collected from all twenty-eight districts of Bulgaria in the period of 2020–2022 in order to determine their physicochemical properties as well as their antioxidant and antimicrobial potential. The raw propolis samples exhibited brown or green colour depending on the climatic zone from which they are collected and pH values from 4.82 to 5.87, while the moisture content ranged between 0.98% and 2.97%. The total phenolics content (TPC) and total flavonoids content (TFC) varied from 63.14 mg GAE/g to 737.27 mg GAE/g, and from 29.22 mg QE/g to 234.17 mg QE/g, respectively. The propolis samples demonstrated significant antioxidant potential determined by DPPH and FRAP methods, from 18.56 mM TE/g to 1598.66 mM TE/g and from 82.28 mM TE/g to 1208.81 mM TE/g, respectively, whose values showed a positive correlation (r2) with the TPC and TFC. The results from the antimicrobial screening revealed that the methanolic propolis extracts in concentration of 20 mg/ml exhibited the highest inhibitory effect on the Gram-positive bacteria such as Micrococcus luteus 2YC-YT, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, Listeria monocytogenes NBIMCC 8632 and Listeria innocua ATCC 33090. [ABSTRACT FROM AUTHOR]

In this study, 106 bacterial strains were isolated from rhizosphere of Deschampsia antarctica and used for the screening of potential antimicrobial compounds. Among all the bacterial strains, 61 (57.55%) were classified as Gram-positive, 34 (32.08%) as Gram-negative, and 11 (10.37%) did not grown under the laboratory culture conditions and were not classified. Organic crude extracts were analysed for potential antimicrobial activity and the B-22-EA ethyl acetate extract was the most effective inhibiting 84% of Escherichia coli growth, and Staphylococcus aureus, Pseudomonas aeruginosa and Micrococcus luteus by 31, 17 and 5%, respectively. The B-22-EA extract showed a MIC of 187 µg/mL on Cryptococcus neoformans, and of 438 µg/mL on Trichophyton rubrum. The strain, coded as B22, was classified as Gram-positive and the taxonomic analysis indicated that this strain belongs to the genera Janibacter, with 98.66% of similarity with Janibacter hoylei PVAS-1 and Janibacter limosus DSM 11140; 98.51% with Janibacter cremeus HR08-44, and 98.36% with Janibacter indicus 0704P10-1, Janibacter anophelis H2.16B and Janibacter terrae CS12. The cellular fatty acids (CFA) composition for B22 (Janibacter sp.) was determined by fatty acid methyl esters (FAME) using gas chromatography and compared with those species for which the B22 strain has a high level of similarity. The comparison among the different species from the genus Janibacter shows that there is a difference in their CFA composition and in their optimum temperature for growth, showing the high biodiversity, even for the same species. The data from this study are important and B-22 (Janibacter sp.) is an interesting source of antimicrobial compounds. [ABSTRACT FROM AUTHOR]

Despite the growing interest in the therapeutic potential of propolis, limited attention has been paid to the chemical composition and biological activity of water extract propolis produced by Malaysian stingless bees. Thus, this study aimed to determine the phytochemical composition and antibacterial potential of ethanolic extract propolis (EEP) and water extract propolis (WEP) of the stingless bee species, Heterotrigona itama against ten pathogenic bacteria. The phytochemical analysis of the extracts was carried out using the gas chromatography-mass spectrometry (GCMS) technique. The antibacterial activity was determined using the disc-diffusion, minimum inhibition concentration (MIC), and minimum bactericidal concentration (MBC) methods. The GC-MS analysis of EEP exhibited four volatile compounds including hexamethylcyclotrisiloxane, 2-hydroxy-2-cyclopenten-1-one, 2-coumaranone, and diethyl bis(trimethylsilyl) ester silicic acid. However, only two compounds were identified in WEP, consisting of 2-(acetoxymethyl)-3-(methoxycarbonyl)biphenylene, and hexamethylcyclotrisiloxane. EEP showed the highest antibacterial activity against all Gram-positive bacteria (Bacillus subtilis, Enterococcus faecalis, Enterococcus faecium, Micrococcus luteus, Staphylococcus aureus, Streptococcus mutans) with values of the inhibition zones ranging from 7 to 10 mm. However, both extracts showed no antibacterial activity against Gram-negative bacteria, except WEP, which displayed an inhibition zone of 9.33 ± 1.53 mm against Escherichia coli. Meanwhile, EEP showed the lowest MIC and MBC values against M. luteus at 70 and 280 μg/mL, respectively. The results revealed the presence of several volatile compounds in the EEP of H. itama which could contribute to its antibacterial activity, particularly against Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

Cinnamomum burmannii (Nees & T. Nees) Blume is a cinnamon species used for daily needs and as an herb in traditional medicine. This study was designed to determine the composition, antioxidant, and antimicrobial activity of essential oils (EOs) extracted from different organs of the plant. The gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS) analysis revealed that the bark was dominated by 1-isopropyl-4,7-dimethyl-1,2,3,5,6,8a-hexahydronaphthalene (11.60%), γ-muurolene (8.79%), eucalyptol (7.66%), α-muurolene (7.37%), α-terpineol (6.65%), δ-selinene (6.42%), while endo-borneol (41.74 and 40.60%), caryophyllene (6.29 and 10.43%), and bornyl acetate (4.18 and 4.08%) were the primary components of branch and leaf oils. Additionally, a notable antioxidant power of the bark, branch and leaf essential oil was observed from the results of 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical scavenging activity (0.03-0.05 mg/mL), antiradical power (ARP) (19.61-32.26), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity assay (0.40-0.75 mol/g), and ferric reducing antioxidant power (FRAP) (0.30-0.66 mg Fe2+/g). Branches and leaves had stronger antioxidant activity, and endo-borneol, bornyl acetate, humulene and cedrene were the main contributors to the antioxidant activity. Moreover, the bark showed notable inhibitory activity against Staphylococcus aureus, while the leaf oil had good antibacterial activity against Micrococcus luteus and Pseudomonas putida. These findings suggest that C. burmannii could be considered a potent source of natural nutraceutical uses. [ABSTRACT FROM AUTHOR]

Antheroporum harmandii Gagnep. is a native plant species of Vietnam, belonging to a small genus of the Fabaceae family. In this study, the bioactivities of different extracts from twigs and seeds of A. harmandii plants collected from Dakrong, Quang Tri province were evaluated. Antimicrobial and antioxidant activities of plant extracts had been done using an agar well diffusion method and DPPH assay. The results showed that methanol, dichloromethane and ethyl acetate extracts from twigs and methanol extract from seeds exerted activities to significantly inhibit two out of nine tested microorganisms. Particularly, the dichloromethane extract from the twigs sample exhibited the highest activity to Micrococcus luteus and Staphylococcus aureus strains with inhibition zones of 4.7 ± 0.3 mm and 2.3 ± 0.2 mm, respectively, at concentrations of 50 mg/mL. The lowest MIC values (500 µg/mL) and 50% inhibition concentration values (IC50) against M. luteus and S. aureus were recorded for the methanol and dichloromethane extracts of twigs. Among tested extracts, the ethyl acetate extract of twigs was the strongest antioxidant, showing radical scavenging potential with IC50 of 117.24 μg/mL. Therefore, A. harmandii species can be suggested as a new source for the isolation of valuable natural compounds. Antheroporum harmandii Gagnep. is a native plant species of Vietnam, belonging to a small genus of the Fabaceae family. In this study, the bioactivities of different extracts from twigs and seeds of A. harmandii plants collected from Dakrong, Quang Tri province were evaluated. Antimicrobial and antioxidant activities of plant extracts had been done using an agar well diffusion method and DPPH assay. The results showed that methanol, dichloromethane and ethyl acetate extracts from twigs and methanol extract from seeds exerted activities to significantly inhibit two out of nine tested microorganisms. Particularly, the dichloromethane extract from the twigs sample exhibited the highest activity to Micrococcus luteus and Staphylococcus aureus strains with inhibition zones of 4.7 ± 0.3 mm and 2.3 ± 0.2 mm, respectively, at concentrations of 50 mg/mL. The lowest MIC values (500 µg/mL) and 50% inhibition concentration values (IC50) against M. luteus and S. aureus were recorded for the methanol and dichloromethane extracts of twigs. Among tested extracts, the ethyl acetate extract of twigs was the strongest antioxidant, showing radical scavenging potential with IC50 of 117.24 μg/mL. Therefore, A. harmandii species can be suggested as a new source for the isolation of valuable natural compounds. [ABSTRACT FROM AUTHOR]

Some 1,4,7,8‐tetrahydro‐5H‐furo[3,4‐b]pyrazolo[4,3‐e]pyridin‐5‐ones containing azo group were synthesized by a three‐component one‐pot reaction of a preformed azoaldehyde (AZA), tetronic acid, and 5‐aminopyrazole in ethanol in the presence of triethylamine under microwave irradiation. The structures of the products were confirmed by spectroscopic data. This method has the advantages of simpler operation to prepare a new dihydropyridines (1,4‐DHPs) ring with multi‐functional groups architecture, high efficiency, short reaction time, and exciting atom economical chemistry. All the products were evaluated regarding antibacterial activities. Some compounds exhibited potent antibacterial activity against both Gram‐negative (Escherichia coli) and Gram‐positive (Micrococcus luteus and Staphylococcus aureus) bacteria compared with erythromycin and tetracycline. The antioxidant activity (AOA) of the synthesized compounds was considered in comparison to vitamin C. Some compounds exhibited the highest AOA, even higher than vitamin C. [ABSTRACT FROM AUTHOR]

Background: Contamination of food by microorganisms from the processing to the consumption stage has become a major health concern in this era, where a better approach for the elongation of food shelf life is explored. This study aims to evaluate the microbial and fungal contamination of different dried cocoyam flakes during storage. Methods: The cocoyam (Colocasia esculenta) samples were properly cooked, peeled, sliced into thin shapes, and dried to constant weights. The drying methods used were sun, hot-air oven, and Nigerian Stored Products Research Institute (NSPRI) multi-crop dryer; samples were divided into three groups A, B, and C, respectively, and the dried samples were stored for three months. Moisture Content (MC) was conducted using the standard method. Colonial morphology, Gram staining, and biochemical test were used to identify and characterize microorganisms. Statistical analyses were performed using SPSS 20.0. Results: There was a significant increase in the MC of all the samples after the storage duration. The sun-dried sample had the highest MC (13.60%) while the oven-dried sample had the lowest MC (10.82%). The sun-dried samples had the highest viable bacteria count (7.2×105 Colony Forming Unit (CFU)/g) and the oven-dried sample had the lowest count (5.1×105 CFU/g). The four bacterial isolates identified were Bacillus subtilis, Pseudomonas aeruginosa, Micrococcus luteus, and Staphylococcus aureus. The heterotrophic fungal number was the highest (0.5×10³ CFU/g) regarding sun-dried samples, whereas the samples dried with NSPRI multi-crop dryer and oven-dried samples had the same value (0.3×10³ CFU/g). Aspergillus flavus, A. niger, Rhizopus, Penicillium, and Mucor were isolated from the samples. Rhyzopertha dominica was identified in sun-dried samples. Conclusion: The increase of MC and the nature of the storage material may have contributed to high bacterial and fungal counts of stored dried cocoyam flakes, especially sun-dried ones, thereby exposing consumers to potential health risks. [ABSTRACT FROM AUTHOR]

Aegle marmelos (L.) or bael commonly known as wood apple, is rich in bioactive compounds has diverse pharmacological importance and is widely employed for the synthesis of green nanoparticles. The current study aims to evaluate the phytochemical components of A. marmelos (L.) by biochemical assays and its antioxidant activity. Further, silver nanoparticles synthesized from A. marmelos (L.) fruit extract exhibited antibacterial effect against pathogens such as Micrococcus luteus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis. The phytochemical screening revealed the phytochemicals such as saponins, flavonoids, alkaloids, phenols, and tannins. UV–Vis spectrophotometry confirms silver ions in the biosynthesized nanoparticles. Further, FT-IR revealed the chemical bonds of alkanes, amines, alcohols, and alkenes. Bioderived silver nanoparticles (AgNPs) showed the highest inhibitory activity against Staphylococcus aureus (29.33 ± 1.59 mm) followed by Enterococcus faecalis (20.14 ± 1.5 mm), Micrococcus luteus (19.33 ± 1.3 mm), Pseudomonas aeruginosa (16.23 ± 1.2 mm), and Escherichia coli (16.13 ± 1.5 mm) at the concentration of 100 µl the highest. The antioxidant activity of different concentrations (25, 50, 100, and 200 µl) of biosynthesized AgNPs were 40%, 46%, 57%, and 61%, respectively. The cytotoxic effect of bioderived nanoparticles on VERO cell lines by MTT assay showed increased cytotoxicity with an increase in concentration and the highest IC50 value recorded at 1000 µg/ml. These results indicate that the bioactive components of A. marmelos (L.) fruit extract exhibited potential antioxidant activity. Bioactive silver nanoparticles showed the highest antibacterial prospects that can be exploited in new drug and antiseptic lotion formulations of herbal origin with sustainable synthesis and application. [ABSTRACT FROM AUTHOR]

Households, restaurants, canteens, and hotel wastes constitute kitchen waste. Every day our growing cities generate more and more waste, which is overloading our municipal systems. The main aim of the present work was to prepare a microbial consortium that can effectively and rapidly bring about the degradation of kitchen wastes that can be used in agricultural soils. More than 100 different bacterial isolates were obtained from various kitchen waste dumping areas. The bacterial isolates were studied to produce enzymes like amylase, gelatinase, lipase, and protease on respective media plates. The best 20 isolates were subjected to enzyme quantification. The isolates showing maximum production for all four enzymes were selected for consortia preparation. The consortia of isolates were prepared by permutation combinations. Amongst all consortia prepared consortium No. 7 showed maximum enzymatic potential. The bacterial isolates in the best consortium (No. 7) were further characterized and identified as KW104 Serratia marcescens, KW37 Micrococcus luteus, KW128 Brevindimonas mediterranea, KW91 Bacillus tequilensis, and KW97 Exiguobacterium mexicanum. This consortium showed rapid degradation of waste as compared to others in 15 days duration of time showing good potential for compost formation when applied to plant growth. [ABSTRACT FROM AUTHOR]

Pomegranate crops are prone to wilt complex disease, which is known to severely hamper the crop yield. There have been limited studies that have explored bacteria–plant–host associations in wilt complex disease affecting pomegranate crops. In the present study, wilt infected rhizosphere soil samples (ISI, ASI) in pomegranate were studied in comparison to a healthy control (HSC). The 16S metagenomics sequencing approach using the MinION platform was employed for screening of bacterial communities and predictive functional pathways. Altered physicochemical properties in the soil samples were recorded showing a comparatively acidic pH in the ISI (6.35) and ASI (6.63) soil samples to the HSC soil (7.66), along with higher electrical conductivity in the ISI (139.5 µS/cm), ASI soil (180 µS/cm), HSC soil sample (123.33 µS/cm). While concentration of micronutrients such as Cl and B were significantly higher in the ISI and ASI soil as compared to the HSC, Cu and Zn were significantly higher in the ASI soil. The effectiveness and accuracy of 16S metagenomics studies in identifying beneficial and pathogenic bacterial communities in multi-pathogen–host systems depend on the completeness and consistency of the available 16S rRNA sequence repositories. Enhancing these repositories could significantly improve the exploratory potential of such studies. Thus, multiple 16S rRNA data repositories (RDP, GTDB, EzBioCloud, SILVA, and GreenGenes) were benchmarked, and the findings indicated that SILVA yields the most reliable matches. Consequently, SILVA was chosen for further analysis at the species level. Relative abundance estimates of bacterial species showed variations of growth promoting bacteria, namely, Staphylococcus epidermidis, Bacillus subtilis, Bacillus megatarium, Pseudomonas aeruginosa, Pseudomonas putida, Pseudomonas stutzeri and Micrococcus luteus. Functional profiling predictions employing PICRUSt2 revealed a number of enriched pathways such as transporter protein families involved in signalling and cellular processes, iron complex transport system substrate binding protein, peptidoglycan biosynthesis II (staphylococci) and TCA cycle VII (acetate-producers). In line with past reports, results suggest that an acidic pH along with the bioavailability of micronutrients such as Fe and Mn could be facilitating the prevalence and virulence of Fusarium oxysporum, a known causative pathogen, against the host and beneficial bacterial communities. This study identifies bacterial communities taking into account the physicochemical and other abiotic soil parameters in wilt-affected pomegranate crops. The insights obtained could be instrumental in developing effective management strategies to enhance crop yield and mitigate the impact of wilt complex disease on pomegranate crops. [ABSTRACT FROM AUTHOR]

Background: The antibiotic resistance in various bacteria is consistently increasing and is posing a serious threat to human health, prompting the need for the discovery of novel structurally featured natural products with promising biological activities in drug research and development. Endolichenic microbes have been proven to be a fertile source to produce various chemical components, and therefore these microbes have been on a prime focus for exploring natural products. In this study, to explore potential biological resources and antibacterial natural products, the secondary metabolites of an endolichenic fungus have been investigated. Methods: The antimicrobial products were isolated from the endolichenic fungus using various chromatographic methods, and the antibacterial and antifungal activities of the compounds were evaluated by the broth microdilution method under in vitro conditions. The antimicrobial mechanism has been discussed with measuring the dissolution of nucleic acid and protein, as well as the activity of alkaline phosphatase (AKP) in preliminary manner. Chemical synthesis of the active product compound 5 was also performed, starting from commercially available 2,6-dihydroxybenzaldehyde through a sequence of transformations that included methylation, the addition of propylmagnesium bromide on formyl group, the oxidation of secondary alcohol, and the deprotection of methyl ether motif. Results: Among the 19 secondary metabolites of the endolichenic fungus, Daldinia childiae (compound 5) showed attractive antimicrobial activities on 10 of the 15 tested pathogenic strains, including Gram-positive bacteria, Gramnegative bacteria, and fungus. The Minimum Inhibitory Concentration (MIC) of compound 5 for Candida albicans 10213, Micrococcus luteus 261, Proteus vulgaris Z12, Shigella sonnet, and Staphylococcus aureus 6538 was identified as 16 mg/ml, whereas the Minimum Bactericidal Concentration (MBC) of other strains was identified as 64 mg/ml. Compound 5 could dramatically inhibit the growth of S. aureus 6538, P. vulgaris Z12, and C. albicans 10213 at the MBC, likely affecting the permeability of the cell wall and cell membrane. These results enriched the library of active strains and metabolites resources of endolichenic microorganisms. The chemical synthesis of the active compound was also performed in four steps, providing an alternative pathway to explore antimicrobial agents. [ABSTRACT FROM AUTHOR]

Myxobacteria are part of the phylum Myxococcota, encompassing four orders. Most of them display complex lifestyles and broad predation profiles. However, metabolic potential and predation mechanisms of different myxobacteria remains poorly understood. Herein, we used comparative genomics and transcriptomics to analyze metabolic potentials and differentially expressed gene (DEG) profiles of Myxococcus xanthus monoculture (Mx) compared to coculture with Escherichia coli (MxE) and Micrococcus luteus (MxM) prey. The results showed that myxobacteria had conspicuous metabolic deficiencies, various protein secretion systems (PSSs) and the common type II secretion system (T2SS). RNA-seq data demonstrated that M. xanthus overexpressed the potential predation DEGs, particularly those encoding T2SS, the tight adherence (Tad) pilus, different secondary metabolites (myxochelin A/B, myxoprincomide, myxovirescin A1, geosmin and myxalamide), glycosyl transferases and peptidase during predation. Furthermore, the myxalamide biosynthesis gene clusters, two hypothetical gene clusters and one arginine biosynthesis clusters were highly differential expressed in MxE versus MxM. Additionally, homologue proteins of the Tad (kil) system and five secondary metabolites were in different obligate or facultative predators. Finally, we provided a working model for exhibiting multiple predatory strategies when M. xanthus prey on M. luteus and E. coli. These results might spur applicationoriented research on the development of novel antibacterial strategies. [ABSTRACT FROM AUTHOR]

Geranium robertianum L. is a widely distributed plant used as a traditional herbal medicine, but the knowledge of its biological properties still needs to be improved. Thus, the purpose of this presented research was to assess the phytochemical profile of extracts from aerial parts of G. robertianum, commercially available in Poland and to study their anticancer potential and antimicrobial properties, including the antiviral, antibacterial, and antifungal effects. Additionally, the bioactivity of fractions obtained from the hexane and ethyl acetate extract was analyzed. The phytochemical analysis revealed the presence of organic and phenolic acids, hydrolysable tannins (gallo- and ellagitannins), and flavonoids. Significant anticancer activity was found for G. robertianum hexane extract (GrH) and ethyl acetate extract (GrEA) with an SI (selectivity index) between 2.02 and 4.39. GrH and GrEA inhibited the development of HHV-1-induced cytopathic effect (CPE) in virus-infected cells and decreased the viral load by 0.52 log and 1.42 log, respectively. Among the analyzed fractions, only those obtained from GrEA showed the ability to decrease the CPE and reduce the viral load. The extracts and fractions from G. robertianum showed a versatile effect on the panel of bacteria and fungi. The highest activity was observed for fraction GrEA4 against Gram-positive bacteria, including Micrococcus luteus ATCC 10240 (MIC 8 μg/mL), Staphylococcus epidermidis ATCC 12228 (MIC 16 μg/mL), Staphylococcus aureus ATCC 43300 (MIC 125 μg/mL), Enterococcus faecalis ATCC 29212 (MIC 125 μg/mL), and Bacillus subtilis ATCC 6633 (MIC 125 μg/mL). The observed antibacterial effect may justify the traditional use of G. robertianum to treat hard-to-heal wounds. [ABSTRACT FROM AUTHOR]

The essential oil of Myristica fragrans Hutt. (nutmeg) is an important commodity used as a flavoring agent in the food, pharmaceutical, and cosmetic fields. Hydrodistillation is chiefly employed at the industrial scale for nutmeg essential oil isolation, but such a technique generates large quantities of post-distillation by-products (e.g., spent plant material and residual distillation water). Therefore, our work aimed to propose a novel strategy for the valorization of nutmeg wastes, with beneficial economic and ecological advantages. Thus, the current study assessed the phytochemical (GC-MS, LC-HRMS/MS) and biological (antioxidant, enzyme inhibitory, antimicrobial) profile of nutmeg crude materials (essential oil and total extract) and post-distillation by-products (residual water and spent material extract). Identified in these were 43 volatile compounds, with sabinene (21.71%), α-pinene (15.81%), myristicin (13.39%), and β-pinene (12.70%) as the main constituents. LC-HRMS/MS analysis of the nutmeg extracts noted fifteen metabolites (e.g., organic acids, flavonoids, phenolic acids, lignans, and diarylnonanoids). Among the investigated nutmeg samples, the spent material extract was highlighted as an important source of bioactive compounds, with a total phenolic and flavonoid content of 63.31 ± 0.72 mg GAE/g and 8.31 ± 0.06 mg RE/g, respectively. Moreover, it showed prominent radical-scavenging and metal-reducing properties and significantly inhibited butyrylcholinesterase (4.78 ± 0.03 mg GALAE/g). Further, the spent material extract displayed strong antimicrobial effects against Streptococcus pneumoniae, Micrococcus luteus, and Bacillus cereus (minimum inhibitory concentrations of 62.5 mg/L). Overall, our study brings evidence on the health-promoting (antioxidant, anti-enzymatic, antimicrobial) potential of nutmeg post-distillation by-products with future reference to their valorization in the pharmaceutical, cosmeceutical, and food industries. [ABSTRACT FROM AUTHOR]

A new member of the surfactin family of microbial lipopeptides has been isolated from the cell broth of Bacillus subtilis TD7 using a combination of organic solvent extraction and RP-HPLC, and its primary chemical structure was determined by ESI-MS, LC-MS/MS, GC-MS, 1H-NMR, 13C-NMR and amino acid analysis. The surfactin-C17 consists of a β-hydroxy heptadecanoic acid chain and a heptapeptide ring with the sequence of N–Glu–Leu–Leu–Val–Asp–Leu–Leu–C, which is a new member with the longest hydrophobic chain in the surfactin family produced by B. subtilis. Compared with the reported members of surfactins-C11∼16, surfactin-C17 showed a very low critical micelle concentration (CMC) of 4.02 × 10−6 mol L−1 in 10 mM PBS at 25 °C, and a very low surface tension of 28.98 mN m−1 at CMC (γCMC); meanwhile, it inherited a strong antibacterial activity against the Gram-positive Micrococcus luteus with a MIC value of 60 mg L−1, and a higher hemolytic activity on sheep erythrocytes. This work concluded that increasing the hydrophobic chain length of a surfactin certainly contributed to decreasing its CMC and would facilitate the development of environmentally friendly biosurfactants and extend the domain of surfactin biosurfactants to new applications such as in pharmaceutical, bioremediation and detergent industries. [ABSTRACT FROM AUTHOR]

The aim of the experiment was to study the enrichment process, chemical composition and antibacterial activity of tea tree hydrosol. D101 macroporous adsorption resin and AB-8 macroporous adsorption resin were used to enrich the chemical components of tea tree hydrosol. Two etho-aqueous solutions with different concentrations of 50% and 95% were selected as eluting agents. The D101 and AB-8 macroporous adsorption resin columns were eluted with 50% ethanol solution, and then the two resin columns were eluted with 95% ethanol solution. The chemical constituents of the crude extracts were analyzed by GC-MS, and determined the antibacterial activity of the crude extracts. The results showed that the main chemical components of M1-95% crude extract enriched by D101 macroporous adsorption resin were terpine-1-ol, γ-terpinene, 1,8-Cineole and α-terpinene. The main chemical components of M2-95% crude extract enriched by D101 macroporous adsorption resin and again by AB-8 macroporous adsorption resin were terpine-1-ol, γ -terpinene, 1, 8-Cineole and α -terpinene. M1-95% showed strong inhibitory activity against Candida albicans, Bacillus subtilis and Micrococcus luteus. M1-50% showed moderate inhibitory activity against Candida albicans, Bacillus subtilis, Micrococcus luteus and Klebsiella pneumoniae. The study indicates that D101 macroporous adsorption resin has strong enrichment ability for chemical components in tea tree hydrops, while AB-8 macroporous adsorption resin does not enrich other chemical components, so the production workshop does not need to enrich the runoff through AB-8 macroporous adsorption resin again. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the chemical composition and antibacterial activity of essential oils of Cymbopogon citratus (CCEO), Cymbopogon khasianus (CKEO), and Mentha arvensis (MAEO) against two Gram-negative (Escherichia coli, Klebsiella pneumoniae) and three Gram-positive (Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis) microbial strains and their combination with antibiotics (chloramphenicol, ampicillin, erythromycin) to observe the synergistic behavior between them. The essential oils (EOs) were investigated by the GC-MS (gas chromatography mass spectrometry) method. The synergistic effect between EOs and antimicrobial agents was analyzed by broth dilution assay. (-)-carvone (52.48%), geraniol (57.66%), and citral (37.83%) were the major components identified in EOs of MAEO, CKEO, and CCEO, respectively. According to the antibacterial activity, EOs demonstrated strong antibacterial activity with MIC values ranging from 0.7 to 18 mg/mL. The interaction between the combination of EOs and antibiotics was determined in terms of FICI (Fractional Inhibitory Concentration Index). Some combinations displayed a partial synergistic effect, and some showed a synergistic and others displayed no effect against bacterial strains. The best synergistic action was shown by the combination of CCEO and Chloramphenicol against E. coli with a FICI value of 0.4. Three to four fold reductions in the MIC value of both essential oil and antibiotics were observed. Therefore, this synergistic interaction of the most active EOs with synthetic antibiotics could lead to new combination therapies for combating infections caused by multidrug-resistant microbes at sufficiently low concentrations in the pharmaceutical and food industry. [ABSTRACT FROM AUTHOR]

Background and Aim: Orangutans are an "umbrella species" for conserving tropical forests in Sumatra and Kalimantan. There are remarkable changes between the gut microbiomes of wild and captive Sumatran orangutans. This study aimed to profile gut microbiota of wild and captive Sumatran orangutans. Materials and Methods: Nine fecal samples collected from wild orangutans and nine fecal samples collected from captive orangutans were divided into three replicates. Each replicate randomly combined three pieces and were analyzed on the Illumina platform. A bioinformatics study of 16S rRNA according to Qiime2 (Version 2021.4) and microbiome profiling analysis was conducted. Results: The relative abundance of different microbial taxa varied significantly between wild and captive Sumatran orangutans. Among the operational taxonomic units, various proportions of Firmicutes, Proteobacteria, Bacteroidetes, Euryarchaeota, Acidobacteria, Actinobacteria and Verrucomicrobia predominated. Solobacterium was found only in 19% of captive orangutans. Methanobrevibacter was identified to be prevalent among wild orangutans (16%). Analysis of the core microbiome from the combined wild and captive data revealed seven species as cores. According to linear discriminant analysis effect size, Micrococcus luteus, Bacteroidescaccae, Lachnospiraceae bacterium, Ruthenibacterium lactatiformans, Haemophilus haemolyticus, and Chishuiella spp. were microbiome biomarkers in captive orangutans, whereas Roseburia inulinivorans, Collinsella aerofaciens, Oscillibacter spp., and Eubacterium hallii were microbiome biomarkers in wild orangutans. Conclusion: There were differences in the microbiome biomarkers of wild and captive Sumatran orangutans. This study is important for understanding the role of gut bacteria in the health of Sumatran orangutans. [ABSTRACT FROM AUTHOR]

The optimal conditions for C3 oxidative biotransformation of 1.0 g/L pentacyclic triterpenoids oleanolic (OA) and glycyrrhetinic (GA) acids were determined using the resting cells of Rhodococcus rhodochrous IEGM 1360 from the Regional Specialised Collection of Alkanotrophic Microorganisms. Resting cell suspensions (OD600 2.6, pH 8.0, and OD600 2.2, pH 6.0) showed the highest catalytic activity against OA and GA, resulting in the formation of 61 and 100% of their 3-oxo derivatives, respectively. Using phase contrast, atomic force, and confocal laser scanning microscopy, an adaptive response of rhodococci to the effects of OA and GA was revealed. In silico, the apoptotic activity of 3-oxo-OA and antioxidant activity of 3-oxo-GA have been assumed. In vitro, a pronounced antibacterial activity of 3-oxo-OA against Micrococcus luteus, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis was shown. The absence of toxic effects of the above triterpenoids and their 3-oxo derivatives on aquatic objects and plants was demonstrated in silico and in vitro, respectively. [ABSTRACT FROM AUTHOR]

Actinomycetes produce secondary metabolites with many bioactivities such as antimicrobial, which can be useful as alternatives against resistant bacterial strains. Therefore, the screening of new habitats is likely to provide new strains with high potential. In this work, the antimicrobial capacity was used to select Streptomyces sp. strains isolated from Raf Raf forest (Tunisia). From the strain displaying higher activity, FR7, an ethyl acetate extract was prepared under optimized culturing conditions (10 days at 30°C in ISP2 medium with initial pH 8), showing significant antimicrobial activity against Micrococcus luteus and Staphylococcus aureus (MIC = 5 μg ml−1), and Listeria monocytogenes and Pseudomonas aeruginosa (MIC = 20 μg ml−1). The extract displayed strong DPPH radical scavenging activity (IC 50 = 1.3 μg ml−1) and protection of yeast cells from H2O2-induced oxidative stress determined by flow cytometry with dichlorofluorescein diacetate. The crude extract showed the presence of polyketides, with methylsalicylic acid as moiety, a large and diverse group of secondary metabolites with a wide range of bioactivities, including antioxidant and antibacterial. Based on 16S RNA gene sequences, strain FR7 was identified as belonging to genus Streptomyces with high resemblance to S. iakyrus. Streptomyces sp. FR7 has great potential as a source of antibacterial and antioxidant metabolites. [ABSTRACT FROM AUTHOR]

The use of microbial skin health care products that balance one’s skin microbiome mimicking healthy skin is rapidly increasing. Postbiotics have more advantages in terms of safety, shelf life, active peptides, and other active compounds, such as GABA, which benefit human skin. In our previous study, we isolated skin commensal bacteria, i.e., Staphylococcus hominis MBF12- 19J, Staphylococcus warneri MBF02-19J, Micrococcus luteus MBF05-19J, and Bacillus subtilis MBF10-19J. This study aimed to produce a bacterial cocktail (BC) formula of those strains, elevate the BC formula into a ferment lysate (FL), and characterize the activities and test for skin sensitivity. The antibacterial activity was carried out by conducting a competition test using Propionibacterium acnes as an indicator bacterium, whereas the antiradical scavenging activity assay was performed using the DPPH method. Skin sensitivity was tested using the patch test method. The bacterial cocktail was lysed by optimizing the enzymatic and ultrasonication methods, whereas sucrose was added as lyoprotectant to obtain a stable powder FL. Potential activity to inhibit the growth of P. acnes was achieved using a formula of FL consisting of M. luteus MBF05-19J, B. subtilis MBF10-19J, S. warneri MBF02-19J, and S. hominis MBF12-19J at a ratio of 1.5:1.5:0.5:0.5 or equivalent to DNA copy number/mL 1.01E + 16:1.14E + 24:1.96E + 22:1.50E + 18. The skin sensitivity test results showed no sensitivity reaction, guaranteeing that CFS and FL are safe to use for the skin. Sucrose-FL at 12% sucrose formula exhibited higher physical stability than those without. However, the result of potential antiradical scavenging showed mild and very mild activities compared with the use of standard ascorbic acid. [ABSTRACT FROM AUTHOR]

Essential oils are highly concentrated natural extracts obtained from plants, rich in bioactive constituents with antimicrobial properties, but the distinctive climate of the Western Himalayan region influences the same. Aromatic and medicinal plants, viz., Origanum majorana, Origanum vulgare, Cymbopogon winterianus, Pelargonium graveolens, and Nepeta cataria were grown in the foothills of the Western Himalayan condition and evaluated for essential oil content, composition, and their effect on some of the most common pathogenic microorganisms. The essential oil content (%) was 0.77, 0.45, 1.37, 0.15 and 0.17% in O. majorana, O. vulgare, C. winterianus, P. graveolens, and N. cataria, respectively. The major essential oil constituents of the isolated oils were terpinen-4-ol, thymol, citronellal, citronellol, and nepetalactone, contributing 41.24%, 31.81%, 43.13%, 43.35% and 91.43% in O. majorana, O. vulgare, C. winterianus, P. graveolens, and N. cataria, respectively. Well-diffusion assay revealed that the essential oil of O. majorana and O. vulgare was active against both the tested Gram-positive, viz., Bacillus subtilis MTCC 121, Micrococcus luteus MTCC 2470, and Staphylococcus aureus MTCC 96; and Gram-negative, viz., Escherichia coli MTCC 43, Klebsiella pneumoniae MTCC 109, and Pseudomonas aeruginosa MTCC 2453 bacteria, while the essential oil of C. winterianus, P. graveolens, and N. cataria showed activity against only some Gram-positive bacteria. Minimum inhibitory concentration (v/v) values indicated the highest efficacy of O. majorana essential oil against B. subtilis (0.5%), M. luteus (1%), and S. aureus (1%), while O. vulgare was most efficient to E. coli (2%) and K. pneumoniae (2%). C. winterianus essential oil did not inhibit any bacterial strains. M. luteus was susceptible to the essential oil of P. graveolens (1%) and N. cataria (0.5%) at low concentrations. Present findings showed the association between the chemical constituents' profile of isolated essential oils from the Himalayan region and their antimicrobial activity, indicating their perspective to be utilized as antibacterial means. [ABSTRACT FROM AUTHOR]

The study showed the ability to synthesize environmentally friendly silver nanoparticles (AgNPs) using extracts from Wrightia tinctoria seeds and Acacia chundra stems. Surface plasmon resonance peaks in the UV-Vis absorption spectra of both plant extracts verified AgNP synthesis. The structural and morphological properties of the AgNPs were investigated using analytical techniques such as XRD, FTIR, TEM, and EDAX. The AgNPs have an FCC crystalline structure, according to XRD study, and their sizes range from 20 to 40 nm, according to TEM images. Based on the results, these plant extracts have been identified as suitable bioresources for AgNP production. The study also showed that both AgNPs had significant levels of antibacterial activity when tested on four different microbial strains using the agar-well diffusion method. The bacteria tested included two Gram-positive strains (Staphylococcus aureus and Micrococcus luteus) and two Gram-negative strains (Proteus vulgaris and Escherichia coli). Furthermore, the AgNPs were found to have a significant anticancer effect on MCF-7 cell lines, suggesting that they may be useful in therapeutic applications. Overall, this research highlights the potential of the plant extracts considered as a source for synthesizing eco-friendly AgNPs with potential applications in medicine and other fields. [ABSTRACT FROM AUTHOR]

Background: Bioprospecting of actinobacteria isolated from Kubuqi desert, China for antibacterial, antifungal and cytotoxic metabolites production and their structure elucidation. Results: A total of 100 actinobacteria strains were selectively isolated from Kubuqi desert, Inner Mongolia, China. The taxonomic characterization revealed Streptomyces as the predominant genus comprising 37 different species, along with the rare actinobacterial genus Lentzea. The methanolic extracts of 60.8% of strains exhibited potent antimicrobial activities against Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis, Escherichia coli, Salmonella enterica, Saccharomyces cerevisiae and high to mild in vitro cytotoxicity against PC3 (prostate cancer) and A549 (lung carcinoma) cell lines. The metabolomics analysis by TLC, HPLC-UV/vis, HPLC-MS and NMR showed the presence of compounds with molecular weights ranging from 100 to 1000 Da. The scale-up fermentation of the prioritized anti-Gram-negative strain PU-KB10–4 (Streptomyces griseoviridis), yielded three pure compounds including; griseoviridin (1; 42.0 mgL− 1) with 20 fold increased production as compared to previous reports and its crystal structure as monohydrate form is herein reported for the first time, mitomycin C (2; 0.3 mgL− 1) and a new bacterial metabolite 4-hydroxycinnamide (3; 0.59 mgL− 1). Conclusions: This is the first report of the bioprospecting and exploration of actinobacteria from Kubuqi desert and the metabolite 4-hydroxycinnamide (3) is first time isolated from a bacterial source. This study demonstrated that actinobacteria from Kubuqi desert are a potential source of novel bioactive natural products. Underexplored harsh environments like the Kubuqi desert may harbor a wider diversity of actinobacteria, particularly Streptomyces, which produce unique metabolites and are an intriguing source to develop medicinally valuable natural products. [ABSTRACT FROM AUTHOR]

Biofouling is one of the most serious problems in membrane filtration systems for water treatment. An easily applicable antimicrobial finish of polyethersulfone (PES) filter membranes is shown by derivatizing an approved chlorin photosensitizer drug with adhesive ortho-catechol functionalities as known from L-3,4-dihydroxyphenylalanin (Dopa) residues of marine mussel glues. The chemical structure of the second-generation photosensitizer 5,10,15,20-tetrakis(3-hydroxyphenyl)chlorin (m-THPC) is modified by 2-iodoxybenzoic acid (IBX) oxidation, transforming the peripheric meta-phenols of m-THPC into ortho-catechols, and thus improving the adsorption properties ofm-THPC derivatives onto PES material. Stable coatings are formed that preserve chlorin's capability to generate singlet oxygen under visible light illumination. The modification of one or two phenol groups out of the four m-THPC substituents leads to an optimumin the generation of active singlet oxygen, and thus the finish significantly reduces the bacterial growth of gram-negative Escherichia coli and gram-positive Micrococcus luteus on the PES membranes. [ABSTRACT FROM AUTHOR]

Seborrheic dermatitis (SD) is the most prevalent dermatological disease, occurring in up to 50% of newborns, children, and adults around the world. The antibacterial and antifungal resistance contributed to the search for new natural substances and the development of a novel substance based on Melaleuca alternifolia (M. alternifolia) leaf oil (TTO), 1,8-cineole (eucalyptol), and α-(-)-bisabolol. Thus, this work aimed to determine the chemical composition of the novel plant-based substance and to evaluate its antimicrobial activity against standard microorganisms involved in the pathogenesis of SD. Moreover, the chemical composition of the substance was analyzed by gas chromatography coupled with mass spectrometry (GC/MS). Staphylococcus epidermidis (S. epidermidis), Staphylococcus aureus (S. aureus), Micrococcus luteus (M. luteus), and Candida albicans (C. albicans) were used for antimicrobial and antifungal assays by means of the broth microdilution method to determine the minimal inhibitory concentration (MIC). Finally, the substance's ability to inhibit Malassezia furfur (M. furfur) was evaluated. Eighteen compounds from different chemical groups were identified by GC/MS. The major biologically active compounds of the substance were terpinen-4-ol (20.88%), 1,8-cineole (22.28%), (-)-α-bisabolol (25.73%), and o-cymene (8.16%). The results showed that the substance has a synergistic antimicrobial and antifungal activity, while S. epidermidis and C. albicans strains were the most susceptible. Furthermore, the substance inhibited M. furfur, which is a main pathogen involved in the pathogenesis of SD and clinical manifestations. It can be concluded that the novel plant-based substance has a promising potential against M. furfur and scalp commensal bacteria and may be helpful for the development of new drugs for treatment of dandruff and SD. [ABSTRACT FROM AUTHOR]