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Studies on the conditions and pollution routes of antibiotic-resistant bacteria (ARB) in rivers can help provide countermeasures against the spread of ARB. This study focused on the pristine uppermost stream of a river, where Escherichia coli (E. coli) and enterococci were detected, although the stream flows through a pristine forest catchment. Antibiotic resistance of E. coli and enterococci isolated from the river water, riverbed sediment, and feces of waterside animals, such as birds and Mustelidae, were investigated throughout the year in the pristine uppermost sites. Antibiotic resistance was present in 1.4% (7/494) of the E. coli strains and 3.0% (24/812) of the enterococcal strains, and was low throughout the year. Although antibiotic resistance of bacteria isolated from feces was not detected in this watershed, the prevalence of multidrug-resistant E. coli was 0.4% (1/246) and 0.6% (1/172) in river water and riverbed sediment samples, respectively were observed. The presence of extended-spectrum β-lactamase (ESBL)-producing E. coli was confirmed in river water samples, and genomic analysis revealed that the samples possessed the CTX-M-15 group. Multidrug-resistant strains and ESBL-producing strains were classified as phylogroups B1 and A, respectively, which are E. coli phenotypes isolated from wild animals. Pulsed-field gel electrophoresis revealed analysis targeting enterococci that strains isolated from river water and bird feces were in the same cluster with 100% similarity. Therefore, bird feces are a source of enterococci in the uppermost stream of the river. Because multidrug-resistant bacteria and ESBL-producing bacteria were present in the pristine uppermost stream of the pristine river, urgent elucidation of the spreading routes of ARB is important. [ABSTRACT FROM AUTHOR]

Bacterial pustule (BP), caused by Xanthomonas citri pv. glycines, is an important disease that, under favorable conditions, can drastically affect soybean production. We performed a genome-wide association study (GWAS) with a panel containing Brazilian and American cultivars, which were screened qualitatively and quantitatively against two Brazilian X. citri isolates (IBS 333 and IBS 327). The panel was genotyped using a genotyping by sequencing (GBS) approach, and we identified two main new regions in soybeans associated with X. citri resistance on chromosomes 6 (IBS 333) and 18 (IBS 327), different from the traditional rxp gene located on chromosome 17. The region on chromosome 6 was also detected by QTL mapping using a biparental cross between Williams 82 (R) and PI 416937 (S), showing that Williams 82 has another recessive resistance gene besides rxp, which was also detected in nine BP-resistant ancestors of the Brazilian cultivars (including CNS, S-100), based on haplotype analysis. Furthermore, we identified additional SNPs in strong LD (0.8) with peak SNPs by exploring variation available in WGS (whole genome sequencing) data among 31 soybean accessions. In these regions in strong LD, two candidate resistance genes were identified (Glyma.06g311000 and Glyma.18g025100) for chromosomes 6 and 18, respectively. Therefore, our results allowed the identification of new chromosomal regions in soybeans associated with BP disease, which could be useful for marker-assisted selection and will enable a reduction in time and cost for the development of resistant cultivars. [ABSTRACT FROM AUTHOR]

The purpose of this research was to investigate the impact of dietary supplementation of Caragana korshinskii tannin (CKT) on rumen fermentation, methane emission, methanogen community and metabolome in rumen of sheep. A total of 15 crossbred sheep of the Dumont breed with similar body conditions, were divided into three groups (n=5), which were fed with CKT addition at 0, 2 and 4%/kg DM. The study spanned a total of 74 days, with a 14-day period dedicated to adaptation and a subsequent 60-day period for conducting treatments. The results indicated that the levels of ammonia nitrogen (NH3-N) and acetate were reduced (p < 0.05) in rumen sheep fed with 2 and 4% CKT; The crude protein (CP) digestibility of sheep in 2 and 4% CKT groups was decreased(p < 0.05); while the neutral detergent fiber (NDF) digestibility was increased (p < 0.05) in 4% CKT group. Furthermore, the supplementation of CKT resulted in a decrease (p < 0.05) in daily CH4 emissions from sheep by reducing the richness and diversity of ruminal methanogens community, meanwhile decreasing (p < 0.05) concentrations of tyramine that contribute to methane synthesis and increasing (p < 0.05) concentrations of N-methy-L-glutamic acid that do not contribute to CH4 synthesis. However, CH4 production of DMI, OMI, NDFI and metabolic weight did not differ significantly across the various treatments. To sum up, the addition of 4% CKT appeared to be a viable approach for reducing CH4 emissions from sheep without no negative effects. These findings suggest that CKT hold promise in mitigating methane emissions of ruminant. Further investigation is required to evaluate it effectiveness in practical feeding strategies for livestock. [ABSTRACT FROM AUTHOR]

This study aimed to investigate changes in feed intake and ruminal environmental parameters during a high-lipid diet transition in cattle. Eight Nellore steers were fed a control diet composed of 30% hay and 70% concentrate for 21 days, followed by the inclusion of 60 g/kg dry matter of soybean oil for 21 days. The DM intake expressed as a percentage of BW 21 days after lipid inclusion was lower (1.75% BW) than that observed during the control diet feeding (1.81% BW) (P<0.01). Steers fed the control diet had a lower pH than the ruminal pH recorded on days 7, 14, and 21 after lipid inclusion (P=0.034). Lower total short-chain fatty acid production in the rumen and lower microbial nitrogen synthesis were observed on day 7 after lipid inclusion compared to values found when steers were fed the control diet and on days 14 and 21 after lipid inclusion (P=0.041). Lipid inclusion in the diet decreased the population of protozoa on days 7, 14, and 21 (P<0.001). The abundances of R. albus and F. succinogenes were higher when steers were fed the control diet than the abundance observed on days 7, 14, and 21 after lipid inclusion in the diet (P<0.05). The first seven days of lipid diet inclusion are considered the most critical for ruminal adaptation, involving reductions in fibrolytic bacteria and changes in fermentation parameters. After 14 days the rumen showed signs of recovery and adaptation. [ABSTRACT FROM AUTHOR]

Microbial endophytes are microorganisms that live inside plants, and some of them play important yet understudied roles in plant health, growth, and adaptation to environmental conditions. Their diversity within plants has traditionally been underestimated due to the limitations of culture-dependent techniques. Metagenomic profiling provides a culture-independent approach to characterize entire microbial communities. The argan tree (Argania spinosa) is ecologically and economically important in Morocco, yet its seed endophyte microbiome remains unexplored. This study aimed to compare the bacterial and fungal endophyte communities associated with argan seeds collected from six sites across Morocco using Illumina MiSeq sequencing of the 16S rRNA gene and ITS regions, respectively. Bacterial DNA was extracted from surface-sterilized seeds and amplified using universal primers, while fungal DNA was isolated directly from seeds. Bioinformatics analysis of sequencing data identified taxonomic profiles at the phylum to genus levels. The results indicated that bacterial communities were dominated by the genus Rhodoligotrophos, while fungal communities exhibited varying degrees of dominance between Ascomycota and Basidiomycota depending on site, with Penicillium being the most abundant overall. Distinct site-specific profiles were observed, with Pseudomonas, Bacillus, and Aspergillus present across multiple locations. Alpha diversity indices revealed variation in endophyte richness between seed sources. In conclusion, this first exploration of the argan seed endophyte microbiome demonstrated environmental influence on community structure. While facing limitations due to small sample sizes and lack of ecological metadata, it provides a foundation for future mechanistic investigations into how specific endophyte-host interactions shape argan adaptation across Morocco's diverse landscapes. [ABSTRACT FROM AUTHOR]

Antimicrobial agents were produced through submerged and solid substrate fermentation using palm oil mill effluent (POME) and oil palm decanter cake (OPDC) as substrates, respectively. This study aimed to compare the effectiveness of extracts from Streptomyces philanthi RM-1-138 that were obtained from POME and OPDC culture against three strains of bacterial plant pathogens and three strains of oil palm pathogenic fungi. The antimicrobial agents produced in the POME medium could inhibit these pathogens better than those produced in the OPDC medium. The antimicrobial agents exhibited strong antimicrobial activity against Xanthomonas axonopodis pv. glycines and X. campestris pv. campestris (MIC 16 µg ml−1) and Curvularia oryzae and Ganoderma boninense (MIC 128 µg ml−1). The effect of temperature (− 20 to 121 °C for 15 min) and pH (4.0–8.0) on the stability of the antimicrobial agents against C. oryzae was investigated. The antimicrobial agents had excellent stability at the highest temperature and a wide range of pH tests. Identification of these antimicrobial agents produced in POME and OPDC substrate using LC-Q-TOF MS/MS revealed 8 and 6 compounds, respectively. These compounds could be functioned as fungicides (oxadixyl), herbicides (chloreturon), insecticides (isoprocarb and xylylcarb), and antibiotics (anisomycin). Therefore, the POME and OPDC mediums has shown promising potential for being utilized as substitute substrates in the production of antimicrobial agents from S. philanthi RM-1-138. [ABSTRACT FROM AUTHOR]

Desirable characteristics of Staphylococcus sp., Streptococcus sp., Bacillus sp., Klebsiella sp., Escherichia coli, and Pseudomonas pseudoalcaligenes isolated from the trachea of healthy turkeys were evaluated as probiotic candidates in the search for new alternatives to solve antimicrobial resistance issues in poultry. In current study phenotypic and genotypic capacity to produce bacteriocin-like substances, efficacy to inhibit the growth of avian pathogens, susceptibility to antimicrobials of bacteria isolated from the respiratory microbiota of healthy turkeys, and the presence of virulence-associated genes (VAGs) predictors of Avian Pathogenic Escherichia coli (APEC) were evaluated. Nine E. coli and one Klebsiella sp. strains produced bacteriocin-like substances, and all harbored the cvaA gene. Some strains also showed antagonistic activity against APEC. Multidrug-resistant profile was found in 54% of the strains. Six strains of bacteriocin-like substances producing E. coli also harbored 3–5 VAGs. The study showed that two bacterial genuses (Klebsiella sp. and E. coli) present desirable probiotic characteristics. Our results identified strains with potential for poultry's respiratory probiotic. [ABSTRACT FROM AUTHOR]

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Bacteria have evolved multiple sensing strategies to efficiently adapt to their natural hosts and environments. In the context of plant pathology, chemotaxis allows phytopathogenic bacteria to direct their movement towards hosts through the detection of a landscape of plant‐derived molecules, facilitating the initiation of the infective process. The importance of chemotaxis for the lifestyle of phytopathogens is also reflected in the fact that they have, on average, twice as many chemoreceptors as bacteria that do not interact with plants. Paradoxically, the knowledge about the function of plant pathogen chemoreceptors is scarce. Notably, many of these receptors seem to be specific to plant‐interacting bacteria, suggesting that they may recognize plant‐specific compounds. Here, we highlight the need to advance our knowledge of phytopathogen chemoreceptor function, which may serve as a base for the development of anti‐infective therapies for the control of phytopathogens. [ABSTRACT FROM AUTHOR]

Cocoa bean fermentation is typically performed in a spontaneous manner on farms in tropical countries or areas and involves several microbial groups. Metabolism by microbes markedly affects the quality of cocoa beans fermented and the chocolate produced thereof. The present study characterized the microbiota and their metabolic profiles in temperature- and humidity-controlled intra-factory cocoa fermentation in a semitropical area of Japan. Although environmental factors were uniform, the microbiota of cocoa beans subjected to intrafactory fermentation was not stable between tests, particularly in terms of the cell count levels and species observed. Fermentation was sometimes delayed, and fermenting microbes were present at very low levels after 24 hr of fermentation. Due to the unstable microbiota, the profiles of water-soluble compounds differed between tests, indicating the unstable qualities of the fermented cocoa beans. These results suggest the necessity of starter cultures not only in on-farm fermentation but also in machine-controlled intra-factory cocoa fermentation. [ABSTRACT FROM AUTHOR]

Currently, many advances have been made in avoiding food contamination by numerous pathogenic and toxigenic microorganisms. Many studies have shown that different probiotics, in addition to having beneficial effects on the host's health, have a very good ability to eliminate and neutralize pathogens and their toxins in foods which leads to enhanced food safety. The present review purposes to comprehensively discuss the role of probiotics in improving food safety by inactivating pathogens (bacterial, fungal, viral, and parasite agents) and neutralizing their toxins in food products. Some recent examples in terms of the anti-microbial activities of probiotics in the body after consuming contaminated food have also been mentioned. This review shows that different probiotics have the potential to inactivate pathogens and neutralize and detoxify various biological agents in foods, as well as in the host body after consumption., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)