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AbstractIn the present work, the antibacterial and antifungal properties of six new heterocyclic Schiff bases (HSb1, HSb2, HSb3, HSb4, HSb5, HSb6) were evaluated as potential bioactive compounds against the disease-causing pathogenic microorganisms (S.epidermidis, S.aureus, B.cereus RSKK863, E.aerogenes, P.aeroginosa sp., K. pneumonia, S. type H, P.vulgaris, E. coli and (C.albicans Y-1200-NIH). The well-diffusion-method was used to determine the antimicrobial activity. For this purpose, heterocyclic Schiff bases were synthesized by condensation reaction of aldehyde derivatives and thiosemicarbazide derivatives. Spectral analysis techniques (organic elemental analysis, FT-IR,1H-NMR, HRMS, SEM-EDX) were used to characterize the synthesized compounds. It was determined that all the newly synthesized heterocyclic Schiff bases exhibited sound, high or moderate inhibitory effects on the growth of selected different standard antibiotics. [ABSTRACT FROM AUTHOR]

Cronobacter is an emerging bacterial pathogen associated with infections such as necrotizing enterocolitis, sepsis, and meningitis in neonates and infants, related to the consumption of powdered infant formula. In addition, this bacterium can also cause infections in adults by the ingestion of other foods. Thus, this review article aims to report the occurrence and prevalence of Cronobacter spp. in foods of plant origin, as well as the possible sources and routes of contamination in these products, and the presence of pathogenic strains in these foods. Cronobacter was present in a wide variety of cereal-based foods, vegetables, herbs, spices, ready-to-eat foods, and foods from other categories. This pathogen was also found in cultivation environments, such as soils, compost, animal feces, rice and vegetable crops, as well as food processing industries, and domestic environments, thus demonstrating possible contamination routes. Furthermore, sequence types (ST) involved in clinical cases and isolates resistant to antibiotics were found in Cronobacter strains isolated from food of plant origin. The identification of Cronobacter spp. in plant-based foods is of great importance to better elucidate the vehicles and routes of contamination in the primary production chain and processing facility, until the final consumption of the food, to prevent infections. [ABSTRACT FROM AUTHOR]

Cronobacter is an emerging bacterial pathogen associated with infections such as necrotizing enterocolitis, sepsis, and meningitis in neonates and infants, related to the consumption of powdered infant formula. In addition, this bacterium can also cause infections in adults by the ingestion of other foods. Thus, this review article aims to report the occurrence and prevalence of Cronobacter spp. in foods of plant origin, as well as the possible sources and routes of contamination in these products, and the presence of pathogenic strains in these foods. Cronobacter was present in a wide variety of cereal-based foods, vegetables, herbs, spices, ready-to-eat foods, and foods from other categories. This pathogen was also found in cultivation environments, such as soils, compost, animal feces, rice and vegetable crops, as well as food processing industries, and domestic environments, thus demonstrating possible contamination routes. Furthermore, sequence types (ST) involved in clinical cases and isolates resistant to antibiotics were found in Cronobacter strains isolated from food of plant origin. The identification of Cronobacter spp. in plant-based foods is of great importance to better elucidate the vehicles and routes of contamination in the primary production chain and processing facility, until the final consumption of the food, to prevent infections. [ABSTRACT FROM AUTHOR]

The general objective of this work was to isolate from yoghourts cultured strains of lactobacilli with potential for use as probiotics in poultry farming. Three yoghourts were cultured to see the presence of lactobacilli in the Rogosa agar base culture medium. It was found that only one yoghourt (number 1) showed the growth of lactobacilli. This yoghourt was immediately selected for further cultivation. Afterwards, the Lactobacillus strains were isolated and fortified under CO2 and then inoculated into a solution of peptone water, which constituted inoculums to be administered to an experimental group of poultry. Another group served as controls. Pathogenic strains of Escherichia coli were also administered to both groups (experimental and control, each comprising five hens). The results showed significant weight gain from the experimental group (positive effect on immunity) and freedom from disease after an incubation period (inhibitory effect of the lactobacillus strains on the Escherichia coli strains), whereas the control group showed less weight gain than the experimental group and development of colibacillosis after an incubation period. The positive effects of the Lactobacillus strains observed on the poultry of the experimental group proved the ecological role of these microorganisms in improving the health of the poultry by inhibiting the effects of pathogenic Escherichia coli strains. This suggests reassuring prospects for the reduction of antibiotic use in both human and animal care. [ABSTRACT FROM AUTHOR]

The objective of the present study is to the total phenolic compound determination, as well as the in vitro evaluation of methanolic and ethanolic extracts antimicrobial activity of the medicinal plant Mentha rotundifolia L. against pathogenic strains. The Follin-Cioacalteu method was used to determine the total polyphenols, while the flavonoids were estimated according to the colorimetric method with aluminum chloride. In addition, the determination of condensed tannins is performed by the vanillin method. The antimicrobial activity is tested on five pathogenic bacterial strains, two of which are Gram-negative (Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 27853), three Gram-positive (Bacillus cereus ATCC 11778, Staphylococcus aureus ATCC 25923 and Micrococcus leutus ATCC 4698), and one yeast (Candida albicans ATCC 26790), by the diffusion on solid medium and microdilution methods. The ethanolic extract of round leaf mint from the Bechar region is very rich in polyphenols and flavonoids (401.75 ± 0.32 mg GAE/g, 549.75 ± 1.23 mg QE/g) compared to the methanolic and hydroalcoholic extracts of this plant from the Sidi-Bel-Abbes region. The results of the obtained well method showed that all bacterial strains exhibited sensitivity to the ethanolic extract of Mentha rotundifolia L. from the Bechar region, with inhibition zones up to 21,67 ± 0,57 mm and minimum inhibitory concentrations (MIC) varying between 06.25 mg/ml and 100 mg/ml, The effect of the other extracts on the tested strains was less significant, the methanolic extract was the least effective. These results demonstrate that the Mentha rotundifolia L. ethanolic extract has a great potential of secondary metabolites with antimicrobial activity. [ABSTRACT FROM AUTHOR]

Objective To understand the pathogenic bacteria strains in patients with nosocomial infection in the comprehensive ICU of the First Hospital of Shanxi Medical University and to analyse their drug resistance. Methods We retrospectively analyzed the clinical data of patients with nosocomial infection in the comprehensive ICU of the First Hospi‐ tal of Shanxi Medical University from 2017 to 2021，summarized the incidence of infection，pathogenic bacteria species and sites of infection in patients，and analyzed the drug resistance of Gram-negative and Gram-positive bacteria. Results There were 3 608 patients with 532 cases of infections，an incidence of infection of 14. 75% and an incidence of infection cases of 21. 62%，both of which showed a decreasing trend with increasing years. A total of 1 216 pathogenic strains were detected，mainly Gram-negative bacteria of 844(69. 41%)，followed by Gram-positive bacteria of 232(19. 08%)and fun‐ gi of 140(11. 51%). The site of infection in the comprehensive ICU hospitals was predominantly respiratory system，ac‐ counting for 55. 51%. The overall detection rate of carbapenem-resistant Klebsiella pneumoniae was 43. 44%，with a down‐ ward trend over the five-year period. The overall detection rate of Klebsiella pneumoniae with ultra broad spectrum β-lac‐ tamase was 25. 36%，with an increasing trend over the five-year period. The resistance rate of Acinetobacter baumannii to carbapenems，cephalosporins and penicillins was more than 80%，and the detective rate of carbapenem-resistant A. bau‐ mannii was more than 75%；the detection rate of carbapenem-resistant Pseudomonas aeruginosa ranged from 41. 51% to 42. 62%. The resistance rate of Enterococcus faecalis to penicillins and quinolones was more than 90%，and they were sensitive to vancomycin and teicoplanin. The resistance rate of Coagulase-negative staphylococci and Staphylococcus epidermi‐ dis to penicillin antibiotics was more than 80%，and they were sensitive to linezolid，vancomycin and teicoplanin. The de‐ tection rate of methicillin-resistant Staphylococcus aureus ranged from 27. 27% to 35. 71%. Conclusions Gram-nega‐ tive bacteria are the main pathogens of hospital-acquired infections in our comprehensive ICU，with the main site of the re‐ spiratory system. Klebsiella pneumoniae and Acinetobacter baumannii have high rates of drug resistance and some multidrug resistant bacteria are detected at a relatively high rate. [ABSTRACT FROM AUTHOR]

Plant diseases are the serious threat to global food security. Many of the current antimicrobial agents for agriculture are highly toxic and non-biodegradable and cause prolonged environmental pollution. In this present research work, seed extract of corn has been used to reduce silver nitrate for the biosynthesis of silver nanoparticles (AgNPs) and to evaluate antimicrobial activity against pathogenic bacterium and fungus. The synthesised biogenic silver nanoparticles (AgNPs) were characterised by UV-Vis, FTIR, XRD, SEM, EDX, TEM and DLS. Scanning electron microscopic (SEM) and Transmission electron microscope (TEM) elicit the formation of spherical-shaped nanoparticles with an average size of 25 nm. X-ray diffraction revealed the FCC nature of nanoparticles. Biosynthetic AgNPs have been shown to be a valuable inhibitory activity against the phytopathogenic fungus Phomopsis vexans by reducing the growth of mycelium by 30–40% in potato dextrose medium. It has been concluded that corn seed extract is capable of synthesising AgNPs with antifungal activity. [ABSTRACT FROM AUTHOR]

Introduction: Cardamom, also known as Elettaria cardamomum, a venerated perennial herb like the "Queen of Spices" belongs to the Zingiberaceae family. She holds various pharmacological activities due to its phytochemicals it contains such as; phenols, tannins, terpenoids, flavonoids, sterols. Methods: The study included the determination of the chemical composition of Elettaria cardamomum ethanolic extract (EEC) by HPLC/UV and evaluated their antimicrobial potential against ten pathogenic reference strains using two complementary techniques: the method of diffusion from solid discs and the determination of minimum inhibitory concentrations (MIC). Results: The results obtained from chemical identification of the EEC showed the presence of polyphenolic acids (rosmarinic acid, caffeic acid, ferulic acid, etc.) and many flavonoids (kaempferol, chrysin, galangin, pinocembrine, quercetin, etc.). The results of the antimicrobial effect showed that the extract reacted positively on almost all the microbial strains tested. The EEC extract significantly inhibited the growth of microbial strains, with a broader antimicrobial spectrum with extensive action with inhibitory zones between 8 and 33 mm in diameter. Thus, this extract revealed a dose-dependent antimicrobial activity on these microbial strains used. However, the inhibitory potential of the cardamom extract was variable compared to their MIC ranging from 6.25 to 12.5 mg of dry extract/mL. Therefore, the strains least susceptible to EEC are Bacillus subtilis, Escherichia coli, Aspergillus niger and Candida albicans. Conclusion: This activity is due to the phenolic compounds produced by the EEC extract. This extract can be used for the development of plant medicines against microbial infections and fungal infestations. [ABSTRACT FROM AUTHOR]

Background: The microbial infections represent a real public health problem with considerable individual and economical consequences. Their surveillance has become, in recent decades, an essential element of any program to control these infections. Aim: In this study, we estimated the prevalence and frequencies of some microbial infections amongst the Bechar's community (Algeria). Methods: The microbiological analyzes of various pathological samples namely : urine and vaginal discharge, pus, nipple discharge, originally sampled from throat, otitis discharge and effusion liquid, have been carried out in the medical analysis laboratory of Bechar for seven months. Results: The obtained results showed that out of 1458 samples, 506 cases were positive (34.7 %), for some infections, there is a relationship correlation between the infections' frequency and their prevalence with the age and gender of patients, as factors; which the female gender presents 74.7 % of positive cases, a sex-ratio less than 1; besides, the most affected population is aged between 25 and 39 years old. The isolated microbial species, which are the most incriminated agents responsible for the studied infections, were mainly Escherichia coli with an isolation frequency of 87.15 %, followed by coagulase-positive Staphylococci CoPS (5.13 %), Streptococcus sp (3.16 %), fungal species Candida albicans (1.58 %), Coagulase-negative Staphylococci Co NS (1.18 %). However, less than 2 % of infectious agents were recorded for the bacterial strains P. aeruginosa, K. pneumoniae and Enterococcus sp. Conclusion : This study can provide a platform for an effective prevention strategy and can be useful for epidemiological prediction with a decision-making. [ABSTRACT FROM AUTHOR]

Wine has long been under the view of researchers to test it for prospective benefits to human health. Many recent studies have claimed how moderate consumption of wine, can be beneficial for us. The aim of this study was to assess antagonistic activity and probiotic potential of the LAB strains, Lactobacillus brevis, Lactobacillus hilgardii and Lactobacillus plantarum, isolated from wine against pathogenic bacteria. The antimicrobial activity was detected with disc diffusion method against five species of Gram-negative bacteria: Escherichia coli CCM 3988, Klebsiella pneumoniae CCM 2318, Salmonella enterica subsp. enterica CCM 3807, Shigella sonei CCM 1373, Yersinia enterocolitica CCM 5671 and five Gram-positive bacteria: Bacillus thuringiensis CCM 19, Enterococcus faecalis CCM 4224, Listeria monocytogenes CCM 4699, Stapylococcus aureus subsp. aureus CCM 2461, Streptococcus pneumonia CCM 4501. These results showed antagonistic activity and probiotic potential of pathogenic bacteria isolated from wine. The cell free supernatants (CFS) from Lactobacillus brevis, Lactobacillus hilgardii and Lactobacillus plantarum inhibited the growth of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

The present work is emphasised on the bio‐fabrication of silver and gold nanoparticles in a single step by a microwave‐assisted method using the leaf extract of Synedrella nodiflora as both reducing and stabilising agent. The synthesised nanoparticles are highly stable and show surface plasmon resonance peak at 413 and 535 nm, respectively, for silver and gold nanoparticles in UV–Vis spectrum. The functional group responsible for the reduction of metal ions were obtained from Fourier transform infrared spectroscopy. The crystalline nature of nanoparticles with face‐centred cubic geometry was confirmed by the X‐ray diffraction and selected area electron diffraction patterns. The morphology and sizes of the silver and gold nanoparticles were obtained from transmission electron microscopy images. The nanoparticles exhibit effective antimicrobial activities against various pathogenic strains. These antimicrobial properties were analysed by employing agar well diffusion method. The nanoparticles show significant antioxidant properties, and it was determined using 2, 2‐diphenyl‐1‐picrylhydrazyl assay. The nanoparticles also show potent catalytic activity in the degradation of anthropogenic pollutant dyes Congo red and eosin Y by excess NaBH4. Thus, the current study demonstrates the potential use of S. nodiflora as a reducing and stabilising agent for the synthesis of silver and gold nanoparticles and their relevance in the field of biomedicine and catalysis. [ABSTRACT FROM AUTHOR]

Background: Probiotics are live microorganisms which are beneficial bacteria that are normal flora of the digestive system which, in determined amounts, show beneficial effects on host health, and can balance gastrointestinal microflora. Digestive tract diseases such as diarrhea are one of the major causes of child mortality in developing countries. Different pathotypes of Escherichia coli cause diarrhea that affects children, therefore reduction of these colonization strains in humans or animals can decline gastrointestinal disorders such as diarrhea. Objective: The aim of this study was to determine the antimicrobial effect of probiotic bacterial strains isolated from different natural sources against 4 pathotypes of pathogenic E. coli using disk and well diffusion methods. Methods: This cross-sectional study was conducted from December 2013 to July 2014 on Martyr Chamran University in Ahwaz city. A total of 13 probiotic colonies isolated from 20 samples of traditional dairy products including yogurt, cheese and milk, and 20 samples of vegetables including carrots and cabbages (red and white), of which 5 isolates were selected to determine the antimicrobial effect against 4 Escherichia coli pathotypes, randomly. The antimicrobial effect was evaluated using two methods: disk diffusion and well diffusion tests and measuring growth inhibition zones of probiotics against 4 pathotypes of pathogenic E. coli. Results: Obtained results showed growth inhibition effects of all 5 probiotic strains against Escherichia coli pathotypes in both used methods. But in comparison Lactobacillus plantarum had higher growth inhibitory effects in both methods. Conclusion: results of this study demonstrated high antimicrobial effect of probiotic bacteria against pathogenic Escherichia coli strains. It indicated a positive and beneficial role of probiotics in human health and prevention of illness. [ABSTRACT FROM AUTHOR]

The current research study focuses on biosynthesis of silver nanoparticles (Ag NPs) for the first time from silver acetate employing methanolic root extract of Diospyros assimilis. The UV–Vis absorption spectrum of biologically synthesised nanoparticles displayed a surface plasmon peak at 428 nm indicating the formation of Ag NPs. The influence of metal ion concentration, reaction time and amount of root extract in forming Ag NPs by microscopic and spectral analysis was thoroughly investigated. Structural analysis from transmission electron microscopy confirmed the nature of metallic silver as face‐centered cubic (FCC) crystalline with an average diameter of 17 nm, which correlates with an average crystallite size (19 nm) calculated from X‐ray diffraction analysis. Further, the work was extended for the preliminary examination of antimicrobial activity of biologically synthesised Ag NPs that displayed promising activity against all the tested pathogenic strains. [ABSTRACT FROM AUTHOR]

A series of transition metal complexes of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) with (Z)- 4-(1-((2-carboxycyclohexa-2,4-dien-1-yl)imino)-ethyl)[bis(η 5 -cyclopenta-1,3-dien-1-yl)]iron (HL) mixed with 1,10-phenanthroline (Phen.) have been synthesized and successfully characterized using various spectrochemical techniques: elemental analyses, molar conductance, IR, 1 H NMR, mass spectroscopy, SEM, thermal analysis (TG/DTG), MOE, biological and anticancer activities. The molecular structures of the HL ligand and its Fe(III) complex were determined by SEM studies. HL ligand acts as a bidentate ligand and coordinates to metal ion center via deprotonated carboxylate oxygen atom and azomethine nitrogen. Also, 1,10-phenanthroline acts as a neutral bidentate ligand coordinates to the metal ion center via two nitrogen atoms. Additionally, mixed ligand complexes were screened against pathogenic antibacterial and antifungal strains: two Gram (+) bacteria; Streptococcus pneumoniae and Bacillis subtilis , two Gram (−); Pseudomonas aeruginosa and Escherichia coli and four fungi; Aspergillus fumigatu , Syncephalastrum racemosum , Geotricum candidum and Candida albicans . The breast cancer cell line MCF7 anticancer activity was studied and a moderate result was the main observation. Molecular docking studies of the HL ligand and its mixed Fe(III), Ni(II) and Cu(II) metal complexes with 1,10-phenanthroline showed the nature of binding energy, H-bond and hydrophobic interactions with the crystal structure of: Tyrosine kinase auto-inhibitor (PDB: 1T46 ), Staphylococcus aureus nucleoside (PDB: 3Q8U ), Human papillomavirus (HPV) pro-apoptotic tumor suppressor (PDB: 4XR8 ) and breast cancer mutant oxidoreductase (PDB ID: 3HB5 ). [ABSTRACT FROM AUTHOR]

A collection of 46 Vibrio harveyi strains were isolated from Epinephelus spp., Lutjanus erythopterus , and other maricultured fish in coastal areas of Hainan Province and Guangdong Province, China, between 2011 and 2013. Eighteen strains were determined to be pathogenic via artificial infection of healthy Epinephelus coioides at 10 7 colony-forming units (CFU) mL − 1 . Mortality occurred within 2 to 6 h after injection. Genotypic assays of the 46 strains by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) revealed a similar genotype profile, referred to as the ERIC-1 profile, for all 18 pathogenic strains. This finding indicates that pathogenic V. harveyi strains in south China have similar genetic backgrounds and might be representative pathogenic strains of this region. All 46 strains were screened for the presence of virulence genes typical of V. harveyi , of zoonotic Vibrio species such as V. cholerae , V. parahaemolyticus , and V. vulnificus and of the aquatic pathogen V. anguillarum . Virulence genes were amplified by PCR using specific primers, and five typical virulence genes of the Harveyi clade, luxR , toxRvh , chiA , serine protease and vhh , were detected in all pathogenic isolates. Non-pathogenic strains carried only 1 to 4 of these genes, indicating that these five genes might be the main virulence genes of ERIC-1 strains. Strain-specific PCR primers were designed based on the sequences of distinct ERIC-PCR bands for the 18 pathogenic strains. Species-specific primers exhibited high specificity and sensitivity. This study demonstrates that bacteria that are highly important to mariculture could be specifically detected using ERIC-PCR fingerprint-based amplification. [ABSTRACT FROM AUTHOR]

In the present study, the effect of different in vitro cultures (callus, in vitro shoots) and commercially available peppercorn extract was investigated for its activity against toxic metabolite-producing strains (Escherichia coli, Pseudomonas aeroginosa, Salmonella typhi, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, and Candida albicans). These in vitro cultures were extracted with ethanol, hexane, and chloroform, and the antipathogenic activity was determined by well-diffusion method. Hexane extract of callus showed 22 mm zone of inhibition against B. cereus, 23 mm against S. aureus, while regenerated shoots and seeds have shown 24.3 and 26 mm zones of inhibition. The ethanolic extracts of regenerated Piper shoots have shown 25 mm activity against S. aureus, 21 mm against B. cereus, and 16 mm in the case of C. albicans in comparison with standard antibiotics. Peppercorn extracts in chloroform and ethanol had shown activities against B. cereus (23.6 mm) and B. subtilis (23.5 mm). During in vitro organogenesis and morphogenesis, cells and tissues produced a comparable phytochemicals profile like mother plant. Morphogenesis is critically controlled by the application of exogenous plant-growth regulators. Such addition alters the hormonal transduction pathways, and cells under in vitro conditions regenerate tissues, which are dependant on the physiological state of cells, and finally enhance the production of secondary metabolites. To the best of our knowledge, this is the first report to compare the antimicrobial potential of in vitro regenerated tissues and peppercorn with standard antibiotics. In conclusion, most of the extracts showed pronounced activities against all the pathogenic microbes. This is a preliminary work, and the minimum inhibitory concentration values needs to be further explored. Regenerated tissues of P. nigrum are a good source of biologically active metabolites for antimicrobial activities, and callus culture presented itself as a good candidate for such activities. [ABSTRACT FROM AUTHOR]

Green synthesis of metallic nanoparticles has lured the world from the chemical and physical approaches owing to its rapid, non‐hazardous and economic aspect of production mechanism. In this study, silver nanoparticles (AgNPs) were synthesised using petal extracts of Hibiscus rosa‐sinensis. The AgNPs displayed characteristic surface plasmon resonance peak at around 421 nm having a mean particle size of 76.25 ± 0.17 nm and carried a charge of −41 ± 0.2 mV. The X‐ray diffraction patterns displayed typical peaks of face centred cubic crystalline silver. The surface morphology was characterised by scanning electron microscopy and atomic force microscopy. Fourier transform infrared spectroscopy studies confirmed the surface modifications of the functional groups for the synthesis of AgNPs. Furthermore, the synthesised AgNPs displayed proficient antimicrobial activity against pathogenic strains of Vibrio cholerae, Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum is a well-known soil-borne fungi and it is difficult to control their pathogenic strains by conventional strategies. The cultures of two strains of Trichoderma harzianum (T16 and T23) were examined in laboratory conditions and with pot experiments for the control of pathogenic strains of Fusarium oxysporum f. sp. melongenae (Fomg), Fusarium oxysporum f. sp. lycopersici (Fol), Fusarium oxysporum f. sp. niveum (Fon) and F. oxysporum f. sp. melonis (Fom). The T16 and T23 strains showed significant inhibition of mycelial growth in the pathogenic strains of F. oxysporum and the maximum inhibition were recorded when the T. harzianum strain T16 was used (72.69%). Both T. harzianum strains produced volatile and non-volatile metabolites that inhibited growth of F. oxysporum strains on PDA medium. In vitro colonization study demonstrated the root-colonizing ability of these antagonists. The interaction between T. harzianum isolates (T16 and T23) and pathogenic F. oxysporum hyphae showed no overgrowth, hyphal coiling, cell wall degradation or any hyphal penetration around any of the tested F. oxysporum hyphae. Pre-treatment of soil with T16 significantly reduced the severity of Fusarium wilt disease. The disease severity in control plants reached to 90-95% whereas those of the T16-Fomg and T16-Fol treated seedlings of eggplants were 37.74% and 47.12%, respectively, on the 21st day. In this study, while both T. harzianum isolates had a considerable antagonistic effect on the tested pathogens, T16 was found to be more successful than T23. The strong repressive effect of T. harzianum (T16) towards pathogenic Fusarium oxsporum can be applied in biological control of these pathogens. [ABSTRACT FROM AUTHOR]

Sulfated polysaccharides were extracted from gray triggerfish (GTSP) and smooth hound (SHSP) skins. Their chemical and physical characteristics were determined using X-ray diffraction and Infrared spectroscopic analysis. The antibacterial activities of GTSP and SHSP against Listeria monocytogenes (ATCC 43251), Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 25922), Salmonella enterica (ATCC 43972) and Enterobacter sp were evaluated by determining clear growth inhibition zone diameters and the minimum inhibitory concentration (MIC) values and by essays in liquid media. GTSP and SHSP were fractionated by a Diethylaminoethyl-cellulose chromatography. Fraction F GII , from GTSP, and fraction F SII , from SHSP, showed the most important inhibitory effects against the tested bacterial species. The sulfated polysaccharides from fish skins did not show hemolytic activity towards bovine erythrocytes. Overall, the results suggested that those polysaccharides could offer promising sources of polysaccharides for future application as dietary ingredients in the nutraceutical industry. [ABSTRACT FROM AUTHOR]

Abstract: The diversity of environmental mycobacteria was studied in water-logged acidic forest soil. Mycobacteria were assessed in upper and lower soil horizons and summer and winter seasons using T-RFLP and sequencing of 16S rRNA gene produced with Mycobacterium-specific primers. Mycobacteria diversity differed between both the two seasons and soil horizons. Cloning revealed the presence of mycobacteria belonging to three major clusters recognized within the genus, i.e. fast-growing, intermediate, and slow-growing species, with unprecedented abundance and diversity of the latter. Two novel clusters of sequences unrelated to the known mycobacteria were identified. This study raises the possibility that forest wetlands could serve as environmental reservoirs for an unexplored diversity of mycobacteria including those related to pathogenic species. [ABSTRACT FROM AUTHOR]

The pathogenicity of smut fungi is initiated by the fusion of two compatible saprotrophic yeasts that give rise to the formation of dikaryotic pathogenic hyphae. It has been described in the literature that complementation assays of auxotrophic yeasts of Ustilago maydis have allowed the isolation of diploid strains that are solopathogenic, i.e. pathogenic in the absence of mating. The occurrence of such strains from germinating teliospores was not investigated. We evaluated the ability of teliospores to generate solopathogenic strains in three species of smut fungi: Sporisorium reilianum f.sp. zeae, U. maydis and Moesziomyces penicillariae. Using an approach based on the stability of pseudohyphae of solopathogenic strains, we isolated the strain SRZS1 from teliospores of S. reilianum. Microscopic observations and analyses of mating-type alleles showed that SRZS1 is monokaryotic and diploid. Inoculation tests on maize plantlets indicated that SRZS1 is infectious. The same protocol was applied to polyteliosporal isolates from M. penicillariae, U. maydis and S. reilianum of diverse geographic origin. Surprisingly, all strains from teliospores of M. penicillariae were solopathogenic, whereas only few solopathogenic strains were obtained from the other two species. The possible incidence of solopathogenic strain production in the biology of these species is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Locally prevalent pathogenic bacteria 189 Gram (−) and 135 Gram (+) strains, all isolated from pediatric patients severely infected, were tested in vitro against 11 essential oils from commercial origin. All the strains showed resistance to selected antibiotics. Cinnamomum verum, Origanum vulgare and Thymus vulgaris exhibited the highest and broadest antibacterial activity. Emphasis is made in the potential implications of these resources, uncommon at the clinical setting of the study, employed against non-commercial, locally pathogenic strains, being a step to submit in the ensuing period essential oils from plants used in Mexican traditional medicine. [Copyright &y& Elsevier]

The tilapias have become one of the most essential and commercial freshwater aquatic products of China. Here, 16S, 18S, and ITS2 rRNA genes were used through high-throughput sequencing (HTS) to investigate the microbiome from sixteen pond-cultured environments of tilapia (Oreochromis niloticus) at the larvae, juvenile, rearing, and harvesting growth stages (n = 4). A total of 8,659,384 high-quality counts and 272,854 OTUs were obtained. Overall, the larvae group comparatively had more taxa of microbes and a higher community richness index than those in the juvenile, rearing, and harvesting groups. The most dominant phyla included cyanobacteria (35.7%) of 16S rRNA gene, Opisthokonta (28.5%) of 18S rRNA gene, and Chlorophyta (59.5%) of ITS2 rRNA gene. There were 585 bacteria, 395 micro-eukaryotic, and 29 fungi (eukaryotes) shared at the genus level. Annotation analyses showed that the most abundant bacterium, micro-eukaryotes, and fungi were Cylindrospermopsis (13%), Cryptomonas (30%), and Nectriaceae (27%), respectively. Besides, 113 significant KEGG pathway annotations were identified, and the most significant proportion was metabolism (52.4%). The relative abundance revealed that the larvae group had higher pathogenic potential and oxidative stress tolerant among nine investigated bacterial phenotypes. Moreover, 12 guild types were identified as the guilds of animal and plant pathogen origin. Importantly, our results demonstrated that the environmental factors of stocking density, temperature, pH, transparency, and dissolved oxygen have significant impacts on the distribution and abundance of eight identified potential pathogens. These results indicated that water quality management should be prioritized in all growth stages of tilapias. Altogether, this is the first robust study to elucidate the detailed characteristics of microbiota in different growth stages of pond cultured tilapias environments. Our results will provide necessary data for environmental regulation, disease prevention and control, and healthy breeding of tilapias. • The first study to report the characteristics of environmental microbiota in Oreochromis niloticus. • The larvae group had the largest number of microbial communities. • The most influential factor was stocking density as determined by using redundancy analysis. • Eight identified potential pathogen were affected by different environmental factors. [ABSTRACT FROM AUTHOR]