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The Dong Taijinar (DT) and Xi Taijinar (XT) Salt Lakes have been extensively researched for their mineral richness. However, the composition and distribution of their microbial communities are still poorly known. In this study, we employed metagenomic sequencing to explore the diversity and potential functions of the microbial populations in DT and XT. Our findings indicate that the salinity levels in DT (332.18–358.30 g/L) were tenfold higher than in XT (20.09–36.83 g/L). Notably, archaea dominated the DT domain at 96.16%, while bacteria prevailed in XT at 93.09%. In DT, the bacterial community comprised 33 phyla and 1717 genera, with Marinobacter emerging as the dominant genus, showing a positive correlation with the total phosphorus content. The archaeal community in DT included four main phyla and 153 genera. The most abundant genera were Natronomonas (24.61%) and Halorubrum (23.69%), which had a strong positive correlation with the concentrations of Na+, Ca2+, and Cl−. Conversely, XT hosted 33 phyla and 1906 bacterial genera, with Loktanella as the dominant genus. The archaeal taxonomy in XT encompassed four phyla and 149 genera. In both salt lakes, Proteobacteria and Euryarchaeota were the most abundant bacterial and archaeal phyla, respectively. Our analysis of the halophilic mechanisms of these microorganisms suggests that the bacteria in XT tend to synthesize compatible solutes, whereas the archaea in DT adopt a 'salt-in' strategy, integrating salt into their cellular machinery to cope with the high-salinity environment. [ABSTRACT FROM AUTHOR]

Simple Summary: Fenugreek seeds, a natural source of bioactive compounds, were tested for their effects on the immune system and gut bacteria of broiler chickens. Broilers were fed three diets: control, low fenugreek seed powder (5 g/kg), and high fenugreek seed powder (10 g/kg). The results showed that fenugreek seeds downregulated genes related to inflammation and antimicrobial defense, suggesting reduced inflammation, and improved immune response. Fenugreek increased the "good" Firmicutes bacteria and decreased the "bad" Actinobacteriota, Gemmatimonadota, and Verrucomicrobiota. It also boosted beneficial Alistipes, Bacteriodes, and Prevotellaceae bacteria. In conclusion, fenugreek seeds positively impact broiler chickens' immune systems and gut bacteria, possibly by influencing how these two systems interact. This suggests the potential for fenugreek as a natural health promoter in poultry production. Fenugreek seeds (FSs) are a natural source of bioactive compounds that may modulate the immune system and gut microbiota in broilers. This study examined the effects of dietary fenugreek seed powder on immune-related gene expression and cecal microbiota composition in broilers. A total of 144 broiler chickens were randomly allocated to three dietary groups, CON (0 g/kg FS, FS5 (5 g/kg FS) and FS10 (10 g/kg FS), each with 6 replicates of 8 birds. Ileum tissues and cecal contents were collected on day 42 for the mRNA expression of inflammation and antimicrobial defense-related genes and cecal microbiome diversity, respectively. The results indicated that fenugreek seeds downregulated mRNA-level inflammation and antimicrobial defense-related genes: IL6, IL8L2, CASP6, PTGS2, IRF7, AvBD9, AvBD10, and AvBD11. Moreover, fenugreek seeds altered the cecal microbial community by increasing the population of Firmicutes and decreasing the population of Actinobacteriota, Gemmatimonadota and Verrucomicrobiota at the phylum level and increasing Alistipes, Bacteriodes and Prevotellaceae at the genera level. These findings suggest that fenugreek seeds have a positive impact on the immunological profile and microbiome of broiler chickens, possibly through the interplay of the immune system and the gut microbiome. [ABSTRACT FROM AUTHOR]

Microorganisms colonizing modern water-based metalworking fluids (MWFs) have been implicated in various occupational respiratory health hazards to machinists. An understanding of the exposure risks from specific microbial groups/genera/species (pathogenic or allergenic) and their endotoxins and the need for strategies for effective, timely fluid management warrant real-time extended tracking of the establishment of microbial diversity and the prevailing fluid-related factors. In the current study, the microbial community composition, succession, and dynamics of a freshly recharged industrial semi-synthetic MWF operation was tracked in real-time over a period of 50 weeks, using a combination of microbiological and molecular approaches. Substantial initial bacterial count (both viable and non-viable) even in the freshly recharged MWF pointed to the inefficiency of the dumping, cleaning, and recharge (DCR) process. Subsequent temporal analysis using optimized targeted genus/group-specific qPCR confirmed the presence of Pseudomonads, Enterics, Legionellae, Mycobacteria (M. immunogenum), Actinomycetes, and Fungi. In contrast, selective culturing using commercial culture media yielded non-specific isolates and collectively revealed Gram-negative (13 genera representing 19 isolates) and Gram-positive (2 genera representing 6 isolates) bacteria and fungi but not mycobacteria. Citrobacter sp. and Bacillus cereus represented the most frequent Gram-negative and Gram-positive isolates, respectively, across different media and Nectria haematococca isolation as the first evidence of this fungal pathogen colonizing semi-synthetic MWF. Unbiased PCR-DGGE analysis revealed a more diverse whole community composition revealing 22 bacterial phylotypes and their succession. Surges in the endotoxin level coincided with the spikes in Gram-negative bacterial population and biocide additions. Taken together, the results showed that semi-synthetic MWF is conducive for the growth of a highly diverse microbial community including potential bacterial and fungal pathogens, the current DCR practices are inefficient in combating microbial reestablishment, and the practice of periodic biocide additions facilitates the build-up of endotoxins and non-viable bacterial population. [ABSTRACT FROM AUTHOR]

Carbon near the Earth's surface cycles between the production and consumption of organic carbon; the former sequesters carbon dioxide while the latter releases it. Microbes attempt to close the loop, but the longer organic matter survives, the slower microbial degradation becomes. This aging effect leaves observable quantitative signatures: Organic matter decays at rates that are inversely proportional to its age, while microbial populations and concentrations of organic carbon in ocean sediments decrease at distinct powers of age. Yet mechanisms that predict this collective organization remain unknown. Here, I show that these and other observations follow from the assumption that the decay of organic matter is limited by progressively rare extreme fluctuations in the energy available to microbes for decomposition. The theory successfully predicts not only observed scaling exponents but also a previously unobserved scaling regime that emerges when microbes subsist on the minimum energy flux required for survival. The resulting picture suggests that the carbon cycle's age-dependent dynamics are analogous to the slow approach to equilibrium in disordered systems. The impact of these slow dynamics is profound: They preclude complete oxidation of organic carbon in sediments, thereby freeing molecular oxygen to accumulate in the atmosphere. [ABSTRACT FROM AUTHOR]

Bacteria associated with marine invertebrate play a fundamental role in the biology, ecology, development and evolution of their hosts. Although many studies have been focused on the microbial populations of benthic and pelagic habitats, little is known about bacteria colonizing tube-dwelling polychaete. In this context, the current study provided the first characterization of the Melinna palmata Grube, 1870 microbiome based on Illumina sequencing of 16S rRNA gene of the polychaete tissue and proximate sediments collected from the Black Sea, Romania, along a 24.2 m – 45.4 m depth-gradient. The diversity, taxonomic composition and deduced functional profile of the tissue and sediments associated bacterial communities were compared and analyzed in relation with the environmental parameters. This polychaete harbored a distinct bacterial assemblage as compared to their sediments and independent on the depth of their habitat, including 8 phyla in tissues dominated by Proteobacteria, and 12 phyla in sediments majorly represented by Actinobacteriota, respectively. At order level, Synechococcales, Rhodobacterales and Actinomarinales were highly represented in the M. palmata microbiome, while Microtrichales, Anaerolineales and Caldilineales were mostly found in sediments. A significant correlation was observed between Cyanobacteria taxa and the dissolved oxygen concentrations in shallow waters impacted by the Danube inputs. Meanwhile, this phylum showed a positive correlation with Planctomycetota colonizing the invertebrate tissues, and a negative one with Actinobacteriota and Chloroflexi found in sediments. The deduced functional profile of these bacterial assemblages suggested the prevalence of the amino acid and carbohydrate metabolism for both analyzed matrices. This pioneering report on the M. palmata microbiome highlighted the environment contribution to bacterial species enrichment of the polychaete, and provided a glimpse on the putative role of microbial communities associated with this marine organism. [ABSTRACT FROM AUTHOR]

Photosynthetic eukaryotes, such as microalgae and plants, foster fundamentally important relationships with their microbiome based on the reciprocal exchange of chemical currencies. Among these, the dicarboxylate metabolite azelaic acid (Aze) appears to play an important, but heterogeneous, role in modulating these microbiomes, as it is used as a carbon source for some heterotrophs but is toxic to others. However, the ability of Aze to promote or inhibit growth, as well as its uptake and assimilation mechanisms into bacterial cells are mostly unknown. Here, we use transcriptomics, transcriptional factor coexpression networks, uptake experiments, and metabolomics to unravel the uptake, catabolism, and toxicity of Aze on two microalgal-associated bacteria, Phycobacter and Alteromonas, whose growth is promoted or inhibited by Aze, respectively. We identify the first putative Aze transporter in bacteria, a 'C4-TRAP transporter', and show that Aze is assimilated through fatty acid degradation, with further catabolism occurring through the glyoxylate and butanoate metabolism pathways when used as a carbon source. Phycobacter took up Aze at an initial uptake rate of 3.8×10-9 nmol/cell/hr and utilized it as a carbon source in concentrations ranging from 10 µM to 1 mM, suggesting a broad range of acclimation to Aze availability. For growth-impeded bacteria, we infer that Aze inhibits the ribosome and/or protein synthesis and that a suite of efflux pumps is utilized to shuttle Aze outside the cytoplasm. We demonstrate that seawater amended with Aze becomes enriched in bacterial families that can catabolize Aze, which appears to be a different mechanism from that in soil, where modulation by the host plant is required. This study enhances our understanding of carbon cycling in the oceans and how microscale chemical interactions can structure marine microbial populations. In addition, our findings unravel the role of a key chemical currency in the modulation of eukaryote-microbiome interactions across diverse ecosystems. [ABSTRACT FROM AUTHOR]

Background: The mare-foal relationship is essential for the well-being and growth of a foal. Mare's milk provides a foal with nutrients, protective immunity, and microbes. Within the first two weeks of life, there is a risk for a foal to suffer from diarrhea, particularly "foal heat diarrhea" which happens at about the time of a mare's estrus cycle but is more likely due to transitions in the microbiota in the foal's gastrointestinal (GI) tract. We hypothesized that this GI microbiota transition could be caused by changes in lysozyme and microbial populations in the mare's milk. To test this hypothesis, fifteen mare-foal pairs were followed in the first 15 days post-foaling. Every other day milk was collected from mares and rectal swabs were collected from foals. Lysozyme activity in the mare's milk was measured using a fluorescence assay. Microbial DNA was isolated from the milk and swabs and the V4 domain of 16 S rRNA genes were PCR amplified and sequenced using Illumina MiSeq technology. Microbial populations were analyzed using DADA2 and phyloseq within R. Results: Mare's milk lysozyme activity peaked for samples at Day 1 and levels dropped to 72.5% of Day 1 activity by Day 15; however, microbial populations in the mare's milk did not vary significantly over the two weeks. Furthermore, levels of microbial diversity found in foal rectal swabs were initially similar to microbial diversity seen in mare's milk; however, over the first fifteen days, diversity increased for the foal rectal swab microbiota and swab microbial populations differed from milk microbes. A transition occurred shifting from microbes from the phylum Proteobacteria early in rectal swabs to those primarily from the phyla Firmicutes and Bacteroidota after the first few days post-foaling. These phyla contained several families and genera of microbes that promote utilization of milk components in healthy gut transition. Microbial abundance levels correlated more with days post-parturition than with lysozyme activity and mare's milk microbial populations. Conclusions: The findings suggest that much of the microbial populations responsible for the transition of the foal's gut comes from sources outside of mare's milk species and levels of lysozyme activity. [ABSTRACT FROM AUTHOR]

Biological cells replicate their genomes in a well-planned manner. The DNA replication program of an organism determines the timing at which different genomic regions are replicated, with fundamental consequences for cell homeostasis and genome stability. In a growing cell culture, genomic regions that are replicated early should be more abundant than regions that are replicated late. This abundance pattern can be experimentally measured using deep sequencing. However, a general quantitative theory linking this pattern to the replication program is still lacking. In this paper, we predict the abundance of DNA fragments in asynchronously growing cultures from any given stochastic model of the DNA replication program. As key examples, we present stochastic models of the DNA replication programs in budding yeast and Escherichia coli. In both cases, our model results are in excellent agreement with experimental data and permit to infer key information about the replication program. In particular, our method is able to infer the locations of known replication origins in budding yeast with high accuracy. These examples demonstrate that our method can provide insight into a broad range of organisms, from bacteria to eukaryotes. Author summary: Biological cells replicate their genome in a planned manner. One way of obtaining experimental information about this plan is by deep sequencing a growing culture of cells. The idea underlying these experiments is that genomic regions that are replicated earlier would be present in higher abundances than regions replicated at a later stage. In this paper, we make use of this idea to obtain precise quantitative information on replication programs from sequencing. As a main application, we infer the locations of origins of replication in budding yeast from sequencing data. Our inference is consistent with direct experimental evidences on the locations of these origins. Our method can be in principle be applied to any organism that can be cultured and sequenced, and has therefore the potential to shed light on the replication program of a broad class of organisms. [ABSTRACT FROM AUTHOR]

The discharge of industrial water requires the removal of its pollutants, where biological wastewater treatment plants (WWTPs) are the most used systems. Biological WWTPs make use of activated sludge (AS), where bacteria are responsible for the removal of pollutants. However, our knowledge of the microbial communities of industrial plants is limited. Understanding the microbial population is essential to provide solutions to industrial problems such as bulking. The aim of this study was to identify at a high taxonomic resolution the bacterial population of 29 industrial WWTPs using 16S rRNA amplicon sequencing. Our results revealed that the main functional groups were dominated by Thauera and Zoogloea within denitrifiers, Dechloromonas in phosphate-accumulating organisms, and Defluviicoccus in glycogen-accumulating organisms. The activated sludge characterization indicated that 59% of the industrial plants suffered from bulking sludge, with DSVI values of up to 448 mL g−1. From the bulking cases, 72% corresponded to filamentous bulking with Thiothrix as the most abundant filament; meanwhile, the other 28% corresponded to viscous bulking sludge in which Zoogloea was the most abundant genus. Furthermore, the bacterial population did not share a core of taxa across all industrial plants. However, 20 genera were present in at least 50% of the plants comprising the general core, including Thauera, Ca. Competibacter, and several undescribed microorganisms. Moreover, statistical analysis revealed that wastewater salinity strongly affected the microbial richness of the industrial plants. The bacterial population across industrial plants differed considerably from each other, resulting in unique microbial communities that are attributed to the specificity of their wastewaters. Key points: • The general core taxa of industrial plants were mostly made up of undescribed bacterial genera. • Filamentous bacteria constituted on average 4.1% read abundance of the industrial WWTPs. • Viscous bulking remains a significant type of bulking within industrial WWTPs. [ABSTRACT FROM AUTHOR]

• High fulvic acid (FA) content impedes NO 2 −-N production in partial nitritation (PN). • EEM-PARAFAC and UV/V is an effective method to characterize the evolution of FA. • The PN process has a high utilization of small molecules with 1–5 kDa. • The removal mechanism of FA was varied under different influent FA concentrations. • Changes of Comamonas, OLB12 and Thauera might be critical for FA removal. This study employed multispectral techniques to evaluate fulvic acid (FA) compositional characteristic and elucidate its biodegradation mechanisms during partial nitritation (PN) process. Results showed that FA removal efficiency (FRE) decreased from 90.22 to 23.11% when FA concentrations in the reactor were increased from 0 to 162.30 mg/L, and that molecular size, degree of aromatization and humification of the effluent FA macromolecules all increased after treatment. Microbial population analysis indicated that the proliferation of the Comamona s, OLB12 and Thauera exhibit high FA utilization capacity in lower concentrations (<50.59 mg/L), promoting the degradation and removal of macromolecular FA. In addition, the sustained increase in external FA may decrease the abundance of above functional microorganisms, resulting in a rapid drop in FRE. Furthermore, from the genetic perspective, the elevated FA levels restricted carbohydrate (ko00620, ko00010 and ko00020) and nitrogen (HAO, AMO, NIR and NOR) metabolism-related pathways, thereby impeding FA removal and total nitrogen loss associated with N 2 O emissions. [Display omitted] [ABSTRACT FROM AUTHOR]

This study evaluates six bamboo species, i.e., Dendrocalamus hamiltonii, Bambusa nutans, Dendrocalamus asper, Bambusa bambos, Bambusa balcooa, and Dendrocalamus strictus, regarding their growth behavior, nutrient uptake, and effect on the soil properties of the Terai region. Various aboveground growth parameters exhibited significant variations with the maximum clump girth (8.60 m) and internodal length (35.37 cm) of B. nutans, which was also reported by the culm diameter (5.70 cm) of D. hamiltonii and the number of culms per clump (65) of D. strictus. The total aboveground biomass ranged from 51.14 Mg.ha-1 in D. asper to 362.56 Mg.ha-1 in D. hamiltonii. The most significant variation in soil properties was observed in the 0-40 cm soil layer. Under D. hamiltonii, the lowest soil bulk density (1.07 g.cm3; 1.21 g.cm3) and the maximum soil porosity (59.00%; 56.40%), soil organic carbon (1.54%; 0.72%), and available soil nitrogen (228.29 kg.ha-1; 173.73 kg.ha-1) were found the 0-40 and 40-80 cm soil layers. Furthermore, significant enhancements in soil microbial population were recorded. Thus, bamboo plantations have great potential to enhance the biomass generation and fertility quotient of fallow lands. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of feeding Iranian propolis extract on performance of Holstein dairy cows. In this study 18 dairy postpartum Holstein cows (120 days in milk (DIM) and body weight of 577±37.54 kg) were used. The experiment was carried out in a period of 29 d (10 d adaptation and 19 d sample collection). The data was analyzed considering a completely randomized design by the GLM procedure of SAS 9.1. In this experiment 3 treatments [A: TMR diet, B: TMR diet + Iranian propolis extract (IPE) 50% (67.50 g/day/animal) and C: TMR diet + IPE 75% (67.50 g/day/animal)] were used. The results of this study showed that adding different concentrations of IPE to dairy cow ration did not have any significant effect (P>0.05) on ruminal pH, but significant decrease (P<0.05) in NH3-N was observed in IPE 75% treatment in comparison with the others. The total population of Ruminococcus albus, Prevotella bryantii, fibrolytic, amylolytic, methanogens and protozoa were counted and a significant difference (P<0.05) was observed in total rumen microbial population. Furthermore, adding IPE to the cow ration did not significantly (P>0.05) change some the blood parameters while statistically changed (P<0.05) the blood concentrations of aspartate aminotransferase, albumin, glucose and protein. The phenolic compounds in propolis changed rumen nitrogen ammonia, rumen short chain fatty acids, rumen microbial population, some blood parameters and fatty acid composition in the milk. These changes improve fermentation process and consequently affect significantly fatty acid composition in milk. [ABSTRACT FROM AUTHOR]

The study explored using a hot-air oven at various temperatures (35, 45, and 55 °C) as a promising alternative to traditional sun-drying for salted shrimp paste production. Comparing drying profiles, fermentation rate, quality, and acceptability with conventional sun-drying (CON), it was found that the alternative hot-air oven led to lower enzymatic activities and degree of hydrolysis during a 30-day fermentation (p < 0.05). Consequently, the alternative samples exhibited lower development of distinctive characteristics (color, browning intensity, formal, ammonia, nitrogen contents, and antioxidant capabilities) resulting in lower sensory scores compared to CON (p < 0.05). Interestingly, microbial populations in hot-air-dried samples were also lower than CON (p < 0.05). Based on PCA biplots and drying duration, drying at 45 °C with a hot-air oven seemed optimal for shrimp paste production. However, adjustments, such as prolonging fermentation or using a starter culture, are needed to make the alternative process comparable to the traditional product. [ABSTRACT FROM AUTHOR]

Simple Summary: Symbiotic bacteria play an essential role in the digestion, detoxification, and nutrient supply of bark and ambrosia beetles. They may even promote the invasiveness and adaptability of invasive beetles. However, as a newly invasive pest in China, the diversity and community structure of bacteria associated with Hylurgus ligniperda is still unclear. This hinders our ability to comprehend their invasion mechanism and ecological adaptability. Therefore, this study revealed the differences in the diversity and community composition of associated bacteria in the beetle's elytra, prothorax, and gut. Our findings revealed that the microbial population of the elytra was distinct from that of the prothorax and gut. Additionally, gender disparities existed throughout the bacterial population of elytra. The distribution of associated bacteria in different organs of males and females may indicate that they undertake different ecological functions. This study will help to understand the bacterial communities that may play important roles in Hylurgus ligniperda. Hylurgus ligniperda (Fabricius) (Curculionidae: Scolytinae) is a new invasive pest beetle in China, which colonized the Shandong province, causing devastating damage. Originating in Europe, it has spread to Oceania, Asia, North and South America. Bacterial associates have been frequently reported to play a vital role in strengthening the ecological adaptations of bark and ambrosia beetles. The environmental adaptability of H. ligniperda may be supported by their associated bacteria. Bacterial communities colonizing different body parts of insects may have different functions. However, little is known about the bacteria associated with H. ligniperda and their potential involvement in facilitating the adaptation and invasion of the beetles into new environments. In this study, we employed high-throughput sequencing technology to analyze the bacterial communities associated with male and female adults of H. ligniperda by comparing those colonizing the elytra, prothorax, and gut. Results showed that the bacterial communities of male and female adults were similar, and the elytra samples had the highest bacterial diversity and richness, followed by the gut, while the prothorax had the lowest. The dominant phyla were Proteobacteria, Firmicutes, and Actinobacteriota, while the dominant genera were Serratia, Lactococcus, Rhodococcus, unclassified Enterobacteriaceae, and Gordonia. Among these, Rhodococcus and Gordonia were the specific genera of endobacteria and ectobacteria, respectively. Differences in the distribution of associated bacteria may suggest that they have different ecological functions for H. ligniperda. The results of functional prediction showed that bacteria were enriched in terpenoid backbone biosynthesis, degradation of aromatic compounds, limonene and pinene degradation, neomycin, kanamycin and gentamicin biosynthesis, indicating that they may assist their beetles in synthesizing pheromones, degrading toxic secondary metabolites of host trees, and antagonizing pathogenic fungi. These results help us understand the interaction between H. ligniperda and bacteria and highlight possible contributions to the invasion process. [ABSTRACT FROM AUTHOR]

Simple Summary: Garlic skin and Artemisia argyi stalk have broad application prospects as agricultural by-products. However, the current research on them is still relatively limited. Therefore, the focus of this study is to explore the rumen degradation characteristics of these two agricultural by-products, the dynamic changes of surface rumen bacteria and the changes of cellulase activity. Our results showed that garlic skin and Artemisia argyi stalk had good rumen degradability and had different effects on rumen bacteria and cellulase activity (β-glucosidase, endo-β-1,4-glucanase, exo-β-1,4-glucanase and neutral xylanase). The results of these studies can better understand the potential of garlic skin and Artemisia argyi stalk in the rumen of ruminants and provide a scientific basis for the rational utilization and development of agricultural by-products. The purpose of this study was to study the chemical composition, rumen degradation characteristics, surface attached microbial community and cellulase activity of garlic skin (GS) and Artemisia argyi stalk (AS), in order to explain their feeding value. Four 14-month-old healthy Min Dong male goats with permanent rumen fistula were selected as experimental animals. The rumen degradation characteristics of GS and AS were determined by using the nylon bag method, and the bacterial composition, cellulase activity and their relationship on the surface of the two groups were analyzed with high-throughput sequencing of 16S rRNA gene. The results showed that in GS and AS, the effective degradation rate (ED) values of dry matter (DM) were 42.53% and 37.12%, the ED values of crude protein (CP) were 37.19% and 43.38%, the ED values of neutral detergent fiber (NDF) were 36.83% and 36.23%, and the ED values of acid detergent fiber (ADF) were 33.81% and 34.77%. During rumen degradation, the richness and evenness of bacteria attached to the AS surface were higher. At the phylum level, Bacteroidetes and Firmicutes were always the main rumen bacteria in the two groups. At the genus level, fiber-degrading bacteria such as Prevotella, Treponema, and Ruminococcus showed higher levels in GS (p < 0.05). Compared with GS, the activity of β-glucosidase (BG enzyme), endo-β-1,4-glucanase (C1 enzyme), exo-β-1,4-glucanase (Cx enzyme) and neutral xylanase (NEX enzyme) attached to AS surface showed a higher trend. Correlation analysis showed that the relative abundance of Succinivibrio and Rikenellaceae_RC9_gut_group was positively correlated with the rumen degradability of nutrients in GS, and the relative abundance of Christensenellaceae R-7_group, Succinivibrio and Ruminococcus was positively correlated with the rumen degradability of nutrients in AS. The conclusion of this study shows that AS has more potential to become ruminant roughage than GS. In addition, this study also revealed the relationship between cellulase activity and bacteria, which provided new information for us to better analyze the effects of GS and AS on the rumen of ruminants and provided an important theoretical basis for the development and utilization of agricultural by-products. [ABSTRACT FROM AUTHOR]

The objective of this work is to explore some key considerations related to the mathematical models applied to anaerobic digestion, which is achieved from a bibliographic research on the mathematical models and the deductive and inductive methods, which allowed us to reach the following conclusions: Mathematical models play a crucial role in understanding and predicting the processes associated with anaerobic digestion. From the characterization of substrate degradation kinetics to the simulation of the dynamic behavior of anaerobic reactors, these models offer a powerful tool for researchers and professionals in the field. The diversity of approaches and techniques used in formulating mathematical models reflects the inherent complexity of anaerobic digestion. From simple kinetic models based on Monod equations to more complex models that take into account microbial population dynamics and mass and energy transfer, there is a range of options available to suit different contexts and research objectives. And the practical applications of mathematical models in anaerobic digestion are numerous and varied. From optimizing the design and operation of wastewater treatment plants to evaluating the potential for biogas production from different substrates, these models offer valuable tools for making informed decisions in the environmental and energy spheres. [ABSTRACT FROM AUTHOR]

Emulsion polymerization was optimized to synthesize polystyrene nanoparticles (NPSt) with tailored sizes by adjusting pH and azobisisobutyronitrile (AIBN) content. An NPSt sample prepared with 20 mg AIBN at pH 8 showed the smallest size (88 nm) and narrowest distribution (24 nm peak width). XRD patterns indicated semi-crystalline nature for this optimized sample. The involvement of synthesized NPSt in the nitrogen (N) cycle enhanced our understanding of nitrogen transformations and the response of microbial populations to polystyrene nanoparticles in the environment. In vitro experiments revealed compatibility of NPSt with tested PGPR strains, with no inhibition zones observed. Furthermore, carrot growth in soil containing 400 mg/kg NPSt showed no significant changes in biomass or shoot height compared to control soil. This demonstrates the NPSt samples had no negative effects on PGPR or soil nitrogen transformations and bacterial communities. Overall, the study optimized the synthesis of NPSt, evaluated environmental impacts on soil nitrogen cycling and PGPR, and found no toxicity of NPSt on PGPR or carrot growth up to 400 mg/kg concentration. The insights contribute to understanding nanomaterial interactions in agricultural systems, highlighting the need to consider the environmental impacts of nanoparticles. [ABSTRACT FROM AUTHOR]

To improve ethanol production, carbon and microbial sources were derived from corncob and molasses. Before investigating simultaneous saccharification and fermentation (SSF), the boiled corncob was vacuum-ensiled and the molasses was diluted. The optimal ensiling time of 4 days increased not only the amount of fermentable sugar but also the population of beneficial microorganisms. The proper dilution of molasses at a ratio of 1:3 molasses to boiled water reduced both the contamination problem and the inhibition of ethanol fermentation. The combination of the ensiled corncob and the diluted molasses could provide a substrate that is suitable for SSF without the addition of enzymes, supplements, or yeast strains. The substrate contained the optimal concentration of initial sugar (174.631 ± 0.975 g/L) and viable microorganisms (1.9×106 ± 0.1×106 CFU/mL of total bacteria and 1.0x105 ± 0.1×105CFU/mL of yeast) that could continue to hydrolyze and ferment carbohydrates in the substrate for the SSF. Using a ratio of 1:3 of ensiled corncob to diluted molasses, a pH of 4.5, and a temperature of 27 °C for 72 h, the SSF produced the highest concentration of ethanol at 93.345 ± 0.062 g/L. This work provides a cost-effective process that requires no enzyme or yeast, is simply technology, and is friendly to the environment, while the remaining solid fraction can be utilized as a suitable feedstock for biogas production. [ABSTRACT FROM AUTHOR]

This investigation aimed to assess the impact of 50, 100, and 200 ppm of neutral electrolyzed water (NEW) on the sensory characteristics, chemical composition, and microbiological quality of fresh chicken breast meat kept for six days at 4±1ºC. The results showed that dipping chicken breast meat samples in NEW at three concentrations (50, 100 and 200 ppm) can improve storage stability and reduce microbial populations compared with the control group. The results on the sixth day of storage revealed that the pH values were 6.41±03, 6.34±02c and 6.32±02d, respectively, and the TBARS values were 0.79±0.02, 0.68±0.05 and 0.50±0.02 respectively. While aerobic plate counts, E. coli, and S. aureus counts were 5.58±0.23, 4.54±0.29, 3.92±0.06; 1.82±0.15, 1.65±0.04, 1.38±0.12 and 1.62±0.07, 1.50±0.01, 1.32±0.02 log CFU/g, respectively, which was lower than the control group in all treatments on day 6. As storage duration extended relative to the control group, dipping chicken breast flesh samples in neutral electrolyzed water, especially at a concentration of NEW200 ppm, obtained the greatest score in sensory characteristics. Over the course of six days of storage, the pH and TBARS values of the meat samples rose in control and all treated groups, but lower values were obtained by treating with 50,100 ppm, while the lowest values were obtained by treating with 200 ppm of NEW. This study found that 200 ppm of NEW is more effective than 50 or 100 ppm. It can be a promising way to increase the shelf life of chicken meat without leaving any hazardous residues and is regarded as a healthy antimicrobial preservative agent for chilled chicken meat kept in a refrigerator. [ABSTRACT FROM AUTHOR]

This article presents a new control approach for the optimal and reliable operation of the microbial fuel cell, as one of the most important sources of renewable energy. Considering several adverse effects on the performance of the microbial fuel cell, including the effects of uncertainty, disturbance, and of course, taking into account the nonlinear dynamics and the necessary conditions for the stable and optimal operation of the fuel cell, this paper presents a novel robust hybrid approach to its performance management. The innovative approach by using adaptive and sliding mode techniques, by focusing on providing a theoretical solution and not changing the structure of the fuel cell, reduces and suppresses the effects of disturbance and uncertainty of the model, and by guaranteeing the stable and reliable operation of the microbial fuel cell in the Lyapunov concept, provides rapid regulation of system states. The results of simulation and comparison in the MATLAB environment show the efficiency and optimal performance of the fuel cell system under the planned control method from the perspective of improving the transient and permanent response. [ABSTRACT FROM AUTHOR]

Two composite soil samples were obtained from Lagos state agricultural field at Ikorodu and Lagos State University (LASU) agricultural field, both fields having over 10 years history of Atrazine application. The soil samples were obtained from 0 - 30cm depth with sterile soil auger. The control soil samples with no previous history of Atrazine application were obtained from Badagry beach at the same depth. Physico-chemical analysis of both composite soil samples (mean pH 4.93) and composite water samples obtained from nearby freshwater stream (mean pH 4.55) at the same depth were determined. Analysis of variance (ANOVA) showed there was significant relationship among the parameter and across the locations the result was not significantly different at 0.05 level of significance. Serial dilution technique was engaged to obtain indigenous microbial population while bacterial atrazine - degraders were obtained using minimal salt medium supplemented with 3% atrazine and fungal species with Sabouraud Dextrose agar (SDA) supplemented with atrazine at 5% respectively. Biodegradation / Time-Course study revealed Atrazine concentration reduction using Spectrophotometric analysis. DNA of some selected isolates were extracted and sequenced using 16S rRNA and ITS methods. The genetic data of these isolates were submitted to the NCBI GeneBank database. The selected Atrazine degraders identities were confirmed as follows; Pseudomonas alcaligenes (MT355448.1), Bacillus mycoides (JX144699.1) and Aspergillus aculeatus (LC496490.1) in the NCBI database. [ABSTRACT FROM AUTHOR]

Orchard crop species can influence the soil microbial population by releasing root exudates, which are compounds released by plant roots into the soil. Some crop species exude compounds that are more beneficial for certain groups of microbes, while others exude compounds that inhibit the growth of certain groups. Additionally, different crop species have different root systems, which can affect the physical structure of the soil and the availability of water and nutrients, which in turn can influence the soil microbial population. This study aimed to determine the soil microbial diversity of some orchards during different seasons to advance knowledge about the role of microbes in the balance of the orchard ecosystem. The research was carried out in a mixed orchard in Iasi county. Effects of season (i.e. autumn, spring and summer) and land use (apple orchard, plum orchard and cherry orchard) on soil microbial populations and microbial community structures were determined using the Petri dish culture method on different culture media. [ABSTRACT FROM AUTHOR]

Introduction and Objective: This study was carried out to investigate the effects of probiotics (lacto-feed) and stevia leaf powder as phytogenic compound in the diet on performance, carcass characteristics, intestinal microbial population and some blood parameters in Japanese quail. Material and Methods: This experiment conducted as a completely randomized design with 320 Japanese quail chicks and mixture of both sexes (average weight 7-9 g), in four treatments, four replications and 20 chickens per replicate. Experimental treatments included: 1-Diet without additives (control), 2- Diet containing probiotic lactofeed (0.02% up to 21 days and 0.01% up to 42 days) 3- Diet containing 1% stevia leaf powder and 4- Diet containing 2% were stevia leaf powder. The effects of probiotic lacto-feed and stevia leaf powder as phytogenic compound in the diet on yield, carcass characteristics, intestinal microbial population and some blood parameters of Japanese quail. Results: The results showed that experimental treatments; there was a significant in weight gain and feed conversion ratio between the experimental treatments (p<0.05), which the treatments containing stevia leaf powder had the highest weight gain and the lowest feed conversion ratio, and the difference increased with increasing the percentage of stevia leaf powder (p<0.05). Carcass weight in treatments containing stevia and lacto-feed was significantly higher than the control treatment (p<0.05). Also, the addition of lacto-feed probiotics and stevia leaf powder caused a significant increase in thigh percentage tin compared to the control group (p<0.05). The control treatment had the highest (1.21%) and the lactofeed treatment had the lowest (0.38%) abdominal fat percentage (p<0.05). The highest of triglyceride and VLDL concentrations was observed in the treatment containing probiotic lacto-feed (p<0.05). Also, the treatments containing Stevia leaves powder had higher triglyceride concentration than the control treatment (p<0.05). Blood glucose was significantly higher in the treatment containing probiotic lactofid and in the treatments containing stevia leaf powder was lower tin compared to the control treatment (p<0.05). The effect of experimental treatments on the total population of Aerobic microbes and Coliform was not significant, while the population of Lactobacillus in treatments containing stevia leaf powder was significantly higher than the control treatment (p<0.05). Conclusion: It can be concluded that the use of stevia leaf powder as a phytogenic compound in the diet improved performance and carcass characteristics of Japanese quail chicks. [ABSTRACT FROM AUTHOR]

In order to solve the abnormal fermentation problems caused by the slow and difficult temperature rise in the saccharification piling during the fermentation of sauce-flavor baijiu under low temperatures in winter. A special oxygen dissolving device made of stainless steel was applied in the second sorghum input of sauce-flavor baijiu, as well as the 1th and 2th rounds of saccharification piling fermentation in this study. In addition, its effects on the saccharification piling temperature, the 1th and 2th rounds of physical and chemical indicators, microbial population, and flavor components are analyzed. The results indicate that the use of a stainless steel oxygen dissolver significantly increased the "piling core" temperature of a saccharification piling and that this improvement was highly correlated with the oxygen dissolver. Additionally, it decreased the water content, sugar concentration, and acidity of the "piling core" of the saccharification piling, all of which were negatively correlated with the height of the dissolved oxygen reactor. Furthermore, the stainless steel special dissolved oxygen device also facilitated the growth and reproduction of saccharification piling microorganisms, particularly yeast. The use of the stainless steel special dissolved oxygen device, therefore, resulted in an increase in the concentration of acetaldehyde, ethyl acetate, propanol, isoamyl alcohol, ß-phenylethanol, ethyl palmitate, and other flavoring compounds. Accordingly, the stainless steel special oxygen dissolving device demonstrates a significant application potential in the 1th and 2th rounds of saccharification piling fermentation of sauce-flavor baijiu. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the impact of potential probiotic strains of lactic acid bacteria (LAB), Apilactobacillus kunkeei EIR/BG-1 isolated from the gut of honeybees, and Enterococcus hirae EIR/CM-2 isolated from cow's milk, on rumen fermentation parameters and microbial population in a highconcentrate diet using a rumen simulation technique (Rusitec). The experiment consisted of 7 days of adaptation and 7 days of data collection. The dietary treatments were as follows: no additives (control), addition of 1 ml/fermenter (108 CFU) of Al. kunkeei EIR/BG-1, and addition of 1 ml/fermenter (108 CFU) of E. hirae EIR/CM-2. Alongside rumen fermentation characteristics, rumen microbial composition was investigated using real-time PCR. Supplementation with LAB strains did not affect ruminal pH, production of methane, and total and individual short chain fatty acids, ammonia-N concentration, dry matter digestibility and total protozoa. However, the abundance of Ruminococcus flavefaciens increased in the Al. kunkeei EIR/BG-1 treatment (P < 0.05). Moreover, the size of R. flavefaciens population in E. hirae EIR/CM-2 was comparable to that in the Al. kunkeei EIR/BG-1 treatment. Selenomonas ruminantium was more abundant in the Al. kunkeei EIR/BG-1 treatment compared to the E. hirae EIR/CM-2 treatment (P < 0.05). The abundance of Streptococcus bovis and Megasphaera elsdenii decreased with both Al. kunkeei EIR/BG-1 and E. hirae EIR/CM-2 supplementations (P < 0.05). In conclusion, Al. kunkeei EIR/BG-1 and E. hirae EIR/CM-2 exhibited beneficial effects on some members of the rumen microbial population, although these effects did not manifest in significant alterations in ruminal fermentation. Further research is required to clarify the probiotic potentials of these LAB strains as feed additives for ruminant rations. [ABSTRACT FROM AUTHOR]

Fusarium species are cosmopolitan soil phytopathogens from the division Ascomycota, which produce mycotoxins and cause significant economic losses of crop plants. However, soils suppressive to Fusarium diseases are known to occur, and recent knowledge on microbial diversity in these soils has shed new lights on phytoprotection effects. In this review, we synthesize current knowledge on soils suppressive to Fusarium diseases and the role of their rhizosphere microbiota in phytoprotection. This is an important issue, as disease does not develop significantly in suppressive soils even though pathogenic Fusarium and susceptible host plant are present, and weather conditions are suitable for disease. Soils suppressive to Fusarium diseases are documented in different regions of the world. They contain biocontrol microorganisms, which act by inducing plants’ resistance to the pathogen, competing with or inhibiting the pathogen, or parasitizing the pathogen. In particular, some of the Bacillus, Pseudomonas, Paenibacillus and Streptomyces species are involved in plant protection from Fusarium diseases. Besides specific bacterial populations involved in disease suppression, next-generation sequencing and ecological networks have largely contributed to the understanding of microbial communities in soils suppressive or not to Fusarium diseases, revealing different microbial community patterns and differences for a notable number of taxa, according to the Fusarium pathosystem, the host plant and the origin of the soil. Agricultural practices can significantly influence soil suppressiveness to Fusarium diseases by influencing soil microbiota ecology. Research on microbial modes of action and diversity in suppressive soils should help guide the development of effective farming practices for Fusarium disease management in sustainable agriculture. [ABSTRACT FROM AUTHOR]

Simple Summary: Semen possesses unique microbiota that are distinct from other microbial populations, such as those in the piglet gut and sow vagina. Environmental variations can result in alterations in the bacterial composition, which might not be detrimental but instead could be essential for sustaining optimal sperm functionality. The present study investigated the seminal microbiota in boars in relation to sperm quality. We found a negative linear relationship between the dominant bacterial orders, specifically potential probiotic bacteria (Lactobacillales) and harmful bacteria (Enterobacterales). Moreover, the abundance of potential probiotic functional bacteria was more frequently observed in high-quality ejaculates. Differences in the abundance of specific small subsets of microbes and their interactions revealed more precise effects on sperm quality than the overall seminal bacterial content (CFU/mL). The findings suggest that alterations in the seminal microbiome are significantly associated with the quality of boar semen, and strategies to increase the richness of functional candidates such as Lactobacillus spp. through herd management practices (e.g., seasonal changes, feeding, microbial exposure, antibiotics, and probiotics use) could create favorable reproductive potentials. The present study was carried out to determine the seminal microbiota of boars and their correlation with sperm quality. A total of 17 ejaculates were collected from 17 Duroc boars and were classified according to sperm quality into two groups: low-quality (n = 8) and high-quality (n = 9). Each ejaculate was subjected to (i) semen evaluation, (ii) bacterial culture and MALDI-TOF identification, and (iii) 16S rRNA gene sequencing and bioinformatic analyses. No difference in the total bacterial count, alpha diversity, and beta diversity between the high-quality group and the low-quality group was detected (p > 0.05). While Globicatella sanguinis was negatively correlated with sperm quality (p < 0.05), Delftia acidovorans was positively correlated with sperm quality (p < 0.05). Lactobacillales (25.2%; LB) and Enterobacterales (10.3%; EB) were the most dominant bacteria and negatively correlated: EB = 507.3 − 0.5 × LB, R2 = 0.24, p < 0.001. Moreover, the abundance of Escherichia-shigella was negatively correlated with LB (r = −0.754, p < 0.001) and positively correlated with Proteus (r = 0.533, p < 0.05). Alysiella was positively correlated with Lactobacillus (r = 0.485, p < 0.05), Prevotella (r = 0.622, p < 0.01), and Staphylococcus (r = 0.489, p < 0.05). In conclusion, seminal microbiota is significantly associated with boar semen qualities. The distributions of the most dominant bacterial genera, the differences in the abundance of small subset microbes, and their correlation appear to have far more impact than the overall seminal bacterial content (e.g., total bacterial count, alpha diversity, and beta diversity) on sperm quality. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes is the etiologic agent of listeriosis, a foodborne disease that poses a threat to public health globally. Chicken meat exhibits heightened susceptibility to L. monocytogenes contamination during butchery. The persistence of this pathogen in the slaughterhouse environment enables recurring contamination of meat products. This study aimed at identifying the sources and transmission routes of L. monocytogenes contamination within an abattoir where it was consistently detected for three consecutive years (2019-2021). Furthermore, the environmental factors aiding contamination along chicken processing lines were determined by surveying the microbiome within the facility. Samples collected in 2019 to 2021 were subjected to culture-dependent analysis to assess the prevalence, serotypes, and multi-locus sequence typing (MLST) of L. monocytogenes. Additionally, the specimens collected in 2021 underwent culture-independent analysis via real-time quantitative polymerase chain reaction (qPCR) and 16S rRNA gene amplicon sequencing to identify the contamination sources and characterize the entire microbial community within the slaughterhouse. L. monocytogenes was isolated only from the clean zone, where the final slaughtering stage occurs. Most strains isolated from the final carcasses showed the same genetic cluster as the isolate in the chilling water and were assigned to MLST profile ST3. Culture-independent qPCR confirmed L. monocytogenes contamination in all samples, excluding postscalding carcasses, prewashed post-evisceration carcasses, and the bleeding areas. Consequently, qPCR enabled more comprehensive identification of L. monocytogenes contamination points than culture-dependent approaches. Moreover, 16S rRNA gene amplicon sequencing demonstrated that psychrotolerant and spoilage-related bacteria with L. monocytogenes-like attributes exhibited enhanced viability in the clean zone and immersion-chilling water. Metagenomics-based source tracking analysis further revealed that the shackles and chilling waters represent predominant sources of cross-contamination between different slaughterhouse zones, whereas the grading and packaging workstations and chilling water in the clean zone were deemed crucial sources affecting final carcass contamination. Collectively, these findings demonstrate through culture-dependent and -independent methods that L. monocytogenes spreads along the slaughter line, contaminating the slaughterhouse. Moreover, by investigating changes in microbial community and bacterial flow along the slaughter line within the facility, the sources influencing carcass contamination can be effectively traced. [ABSTRACT FROM AUTHOR]

Equine glandular gastric disease (EGGD) is a common disease among athletic horses that can negatively impact health and performance. The pathophysiology of this EGGD remains poorly understood. Previous studies using controlled populations of horses identified differences in the gastric glandular mucosal microbiome associated with disease. The objective of this study was to compare the gastric microbiome in horses with EGGD and those without across multiple barns and differing management practices. We hypothesized that alterations in the microbiome of the gastric glandular mucosa are associated with EGGD. A secondary objective was to perform a risk factor analysis for EGGD using the diet and management data collected. Microbial populations of biopsies from normal pyloric mucosa of horses without EGGD (control biopsies), normal pyloric mucosa of horses with EGGD (normal biopsies) and areas of glandular mucosal disruption in horses with EGGD (lesion biopsies) were compared. Lesion biopsies had a different microbial community structure than control biopsies. Control biopsies had a higher read count for the phylum Actinomycetota compared to lesion biopsies. Control biopsies also had an enrichment of the genera Staphylococcus and Lawsonella and the species Streptococcus salivarius. Lesion biopsies had an enrichment of the genera Lactobacillus and Actinobacillus and the species Lactobacillus equigenerosi. These results demonstrate differences in the gastric glandular microbiome between sites of disrupted mucosa in horses with EGGD compared to pyloric mucosa of horses without EGGD. Risk factor analysis indicated that exercise duration per week was a risk factor for EGGD. [ABSTRACT FROM AUTHOR]

The goal of the present work was to determine the effect of different concentrations of an organic carbon source (molasses) on the biooxidation of gold-bearing pyrite−arsenopyrite flotation concentrate, as well as on the composition of microbial populations that formed during the biooxidation process. Biooxidation activity increased with increasing molasses concentration in the medium. Concentration of molasses had a greater effect on the total number of microorganisms, while the relative numbers of microorganisms of different groups did not differ significantly. Thus, it was shown that the use of cheap organic substrates is promising to increase the efficiency of biohydrometallurgical processes. [ABSTRACT FROM AUTHOR]

To obtain guidelines for improving the quality of animal feed on production performance, rumen fermentation, and microbial population in goats. A total of 16 native-bore crossbred goats were used. A randomized complete block design (RCBD) was planned to compare four supplementation forms. There were four different loog-pang kaomark fermented cassava chips and rain tree pods (CRFLK) at proportions 100:0, 60:40, 50:50, and 40:60, respectively. The results of this study found that rice straw intake in terms of kg was higher in goats fed CRFLK 50:50, 60:40, and 40:60. While CP, NDF, and ADF digestibility were increased in goat fed CRFLK 50:50 and 40:60. The concentration of acetic acid was decreased by supplementation of CRFLK (p < 0.05) whereas NH3-N and propionic acid were increased (p < 0.05) by goat fed CRFLK. However, CH4 was decreased (p < 0.05) as a result of supplementation of CRFLK. The goat fed CRFLK decreased the protozoal population (p < 0.05). Moreover, the bacteria population was increased by fed with CRFLK (p < 0.05). This study concluded that feeding concentrate inclusion with CRFLK 50:50 and 40:60 resulted in higher propionic acid, CP digestibility, and lowest CH4 production. [ABSTRACT FROM AUTHOR]

Continuous improvement in the living standards of developing countries, calls for an urgent need of high quality meat and dairy products. The farm animals have a micro-ecosystem in gastro-intestinal tract, comprising of a wide variety of flora and fauna which converts roughages and agricultural byproducts as well as nutrient rich concentrate sources into the useful products such as volatile fatty acids and microbial crude proteins. The microbial diversity changes according to composition of the feed, host species/breed and host's individual genetic makeup. From culture methods to next-generation sequencing technologies, the knowledge has emerged a lot to know-how of microbial world viz. their identification, enzymatic activities and metabolites which are the keys of ruminant's successful existence. The structural composition of ruminal community revealed through metagenomics can be elaborated by metatranscriptomics and metabolomics through deciphering their functional role in metabolism and their responses to the external and internal stimuli. These highly sophisticated analytical tools have made possible to correlate the differences in the feed efficiency, nutrients utilization and methane emissions to their rumen microbiome. The comprehensively understood rumen microbiome will enhance the knowledge in the fields of animal nutrition, biotechnology and climatology through deciphering the significance of each and every domain of residing microbial entity. The present review undertakes the recent investigations regarding rumen multi-omics viz. taxonomic and functional potential of microbial populations, host–diet–microbiome interactions and correlation with metabolic dynamics. [ABSTRACT FROM AUTHOR]

Foodborne pathogen Campylobacter jejuni has been associated with ruminants. The objectives of this experiment were to determine C. jejuni survivability in mixed in vitro rumen microbial populations and the impact on methane production with or without methane inhibitors 2-bromosulfonate (BES) and/or sodium nitrate. When inoculated into rumen microbial populations without or with 0.5 mM BES, 5.0 mM nitrate or their combination, C. jejuni viability decreased from 4.7 ± 0.1 log10 colony forming units (CFU)/mL after 24 h. Loss of C. jejuni viability was greater (P < 0.05) when incubated under 100% CO2 compared to 50% H2:50% CO2, decreasing 1.46 versus 1.15 log units, respectively. C. jejuni viability was also decreased (P < 0.05) by more than 0.43 log units by the anti-methanogen treatments. Rumen microbial populations produced less methane (P = 0.05) when incubated with than without C. jejuni regardless of whether under 100% CO2 or 50% H2:50% CO2. For either gas phase, nitrate was decreased (13.2 versus 37.9%) by the anti-methanogen treatments versus controls although not always significant. C. jejuni-inoculated populations metabolized 16.4% more (P < 0.05) nitrate under H2:CO2versus 100% CO2. Apparently, C. jejuni can compete for H2 with methanogens but has limited survivability under rumen conditions. [ABSTRACT FROM AUTHOR]

Membrane aerated biofilm reactor (MABR) technology is currently garnering wide acceptance as a wastewater treatment technology due to process and operational advantages that have accrued during many years of investigation, but despite these achievements, the challenge of biofilm thickness control still persists. This work was therefore designed to expand the current knowledge of MABR operations, particularly with respect to biofilm thickness management and reactor performance stability. Biofilm thickness was controlled with intermittent washing of the membrane bundle based on a bulk dissolved oxygen (DO) concentration set-point of 0.2 mg/L. This nonaggressive membrane cleaning mechanism subdued biofilm sloughing, but maintained biofilm erosion, which supported the development of a multifunctional biofilm with the thickness and microbial activity adequate to stabilize reactor performance over 185 days. Applied in the treatment of municipal wastewater, the MABR demonstrated average organic carbon and ammonia nitrogen (NH4+─ N) removal efficiencies of 92%±2% and 100%±7.8% , respectively. The total inorganic nitrogen removal reached 84%±5% at mean surface loading rates of 10%±0.7 g COD/m2/d and 0.93±0.07 g N/m2/d within a hydraulic retention time of 2.5 h and with minimal reactor down time. The average biofilm density determined at the end of the study was 17.6 g/L , while the biofilm thickness determined to be 0.49 mm. A 16S rRNA analysis of the MABR microbial population at each stage indicated that a microbial community with sufficient biodiversity and relative abundance for stable reactor performance was sustained. Demonstrating that intermittent membrane cleaning with water effectively stabilized the MABR biofilm thickness, reduced process upsets, and maintained high performance at high substrate loading. The current drive for energy neutrality, drastic reduction in energy costs, and increasingly stringent wastewater discharge rules has led to the quest for the development of energy efficient and effective wastewater treatment technologies. MABR is one of these developing technologies. Compared to traditional biological wastewater treatment methods, MABRs offer improved performance with regards to the removal of pollutants from wastewater and energy efficiency. MABR is a biofilm-based technology, whose success depends on the biofilm thickness. Moreover, a biofilm with adequate thickness is required to maintain the diversity and abundance of the microbial community required for high and stable performance over extended operational periods. But, the effective control of biofilm thickness remains a lingering challenge in the application of MABR technology. In practice, biofilm thickness control is commonly accomplished by promoting biofilm detachment using air bubbles. However, several studies have reported performance upsets and performance lag that can sometimes last up to several months following each biofilm detachment episode due to substantial biofilm loss. This study recommends a biofilm thickness management protocol that involves gentle detachment of loosely bound biofilms through nonaggressive cleaning and cleaning episodes initiated when a set operating condition is attained. [ABSTRACT FROM AUTHOR]

Depleted gas reservoirs are a valuable option for underground hydrogen storage (UHS). However, different classes of microorganisms, which are capable of using free H2 as a reducing agent for their metabolism, inhabit deep underground formations and can potentially affect the storage. This study integrates metagenomics based on Illumina‐NGS sequencing of bacterial and archaeal 16S rRNA and dsrB and mcrA functional genes to unveil the composition and the variability of indigenous microbial populations of four Italian depleted reservoirs. The obtained mcrA sequences allow us to implement the existing taxonomic database for mcrA gene sequences with newly classified sequences obtained from the Italian gas reservoirs. Moreover, the KEGG and COG predictive functional annotation was used to highlight the metabolic pathways potentially associated with hydrogenotrophic metabolisms. The analyses revealed the specificity of each reservoir microbial community, and taxonomic and functional data highlighted the presence of an enriched number of taxa, whose activity depends on both reservoir hydrochemical composition and nutrient availability, of potential relevance in the context of UHS. This study is the very first to address the profiling of the microbial population and allowed us to perform a preliminary assessment of UHS feasibility in Italy. [ABSTRACT FROM AUTHOR]

Soil bacteria spend significant periods in dormant or semi‐dormant states that are interrupted by resource pulses which can lead to periods of rapid growth and intense nutrient competition. Microbial populations have evolved diverse strategies to circumvent competitive interactions and facilitate coexistence. Here, we show that nutrient use of soilborne Streptomyces is temporally partitioned during experimental resource pulses, leading to reduced niche overlap, and potential coexistence. Streptomyces grew rapidly on the majority of distinct 95 carbon sources but varied in which individual resources were utilized in the first 24 h. Only a handful of carbon sources (19 out of 95) were consistently utilized (>95% of isolates) most rapidly in the first 24 h. These consistently utilized carbon sources also generated the majority of biomass accumulated by isolates. Our results shed new light on a novel mechanism microbes may employ to alleviate competitive interactions by temporally partitioning the consumption of carbon resources. As competitive interactions have been proposed to drive the suppression of disease‐causing microbes in agronomic soils, our findings may hold widespread implications for soil management for plant health. [ABSTRACT FROM AUTHOR]

Little is known about early plastic biofilm assemblage dynamics and successional changes over time. By incubating virgin microplastics along oceanic transects and comparing adhered microbial communities with those of naturally occurring plastic litter at the same locations, we constructed gene catalogues to contrast the metabolic differences between early and mature biofilm communities. Early colonization incubations were reproducibly dominated by Alteromonadaceae and harboured significantly higher proportions of genes associated with adhesion, biofilm formation, chemotaxis, hydrocarbon degradation and motility. Comparative genomic analyses among the Alteromonadaceae metagenome assembled genomes (MAGs) highlighted the importance of the mannose‐sensitive hemagglutinin (MSHA) operon, recognized as a key factor for intestinal colonization, for early colonization of hydrophobic plastic surfaces. Synteny alignments of MSHA also demonstrated positive selection for mshA alleles across all MAGs, suggesting that mshA provides a competitive advantage for surface colonization and nutrient acquisition. Large‐scale genomic characteristics of early colonizers varied little, despite environmental variability. Mature plastic biofilms were composed of predominantly Rhodobacteraceae and displayed significantly higher proportions of carbohydrate hydrolysis enzymes and genes for photosynthesis and secondary metabolism. Our metagenomic analyses provide insight into early biofilm formation on plastics in the ocean and how early colonizers self‐assemble, compared to mature, phylogenetically and metabolically diverse biofilms. [ABSTRACT FROM AUTHOR]

The objective of this study was to improve understandings of the rumen microbial ecosystem during ruminal acidosis and responses to feed additives to improve prudent use strategies for ruminal acidosis control. Rumen bacterial and archaeal community composition (BCC) and its associations with rumen fermentation measures were examined in Holstein heifers fed feed additives and challenged with starch and fructose. Heifers (n = 40) were randomly allocated to 5 treatment groups: (1) control (no additives); (2) virginiamycin (VM; 200 mg/d); (3) monensin (MT; 200 mg/d) + tylosin (110 mg/d); (4) monensin (MLY; 220 mg/d) + live yeast (5.0 × 1012 cfu/d); (5) sodium bicarbonate (BUF; 200 g/d) + magnesium oxide (30 g/d). Heifers were fed twice daily a 62% forage:38% concentrate total mixed ration at 1.25% of body weight (BW) dry matter (DM)/d for a 20-d adaptation period with their additive(s). Fructose (0.1% of BW/d) was added to the ration for the last 10 d of adaptation. On d 21 heifers were challenged once with a ration consisting of 1.0% of BW DM wheat and 0.2% of BW fructose plus their additive(s). A rumen sample was collected from each heifer via stomach tube weekly (d 0, 7, 14) and 5 times over a 3.6 h period at 5, 65, 115, 165, and 215 min after consumption of the challenge ration (d 21) and analyzed for pH, and ammonia, d - and l -lactate, volatile fatty acids (VFA), and histamine concentrations and total bacteria and archaea. The 16S rRNA gene spanning the V4 region was PCR amplified and sequenced. Alpha and β diversity and associations of relative abundances of taxa with rumen fermentation measures were evaluated. Rumen BCC shifted among treatment groups in the adaptation period and across the challenge sampling period, indicating the feed additives had different modes of action. The monensin-containing treatment groups, MT and MLY often had similar relative abundances of rumen bacterial phyla and families. The MLY treatment group was characterized in the challenge period by increased relative abundances of the lactate utilizing genera Anaerovibrio and Megasphaera. The MLY treatment group also had increased diversity of ruminal bacteria which may provide resilience to changes in substrates. The control and BUF treatment groups were most similar in BCC. A redundancy analysis showed the MLY treatment group differed from all other treatment groups and concentrations of histamine and valerate in the rumen were associated with the most variation in the microbiota, 5.3% and 4.8%, respectively. It was evident from the taxa common to all treatment groups that cattle have a core microbiota. Functional redundancy of rumen bacteria which was reflected in the greater sensitivity for the rumen BCC than rumen fermentation measures likely provide resilience to changes in substrate. This functional redundancy of microbes in cattle suggests that there is no single optimal ruminal microbial population and no universally superior feed additive(s). In summary, differences in modes of action suggest the potential for more targeted and improved prudent use of feed additives with no single feed additive(s) providing an optimal BCC in all heifers. [ABSTRACT FROM AUTHOR]

Summary: The mezcal industry faces challenges such as overexploitation of wild agaves, poor cooking processes, incomplete fermentation, little control of the distillation process, and the generation of agro‐industrial waste. Successful fermentation is essential to reach a sustainable agave exploitation process in this context. This review focuses on the interactions between different yeast species in alcoholic fermentation, particularly agave fermentation, for mezcal production. A significant variation was observed regarding techniques, fermentation conditions, and yeasts used. These variations influence the chemical composition of alcoholic beverages, especially mezcal. The influence of various factors, such as the processing method, geographic origin, agave species, used, and microbial populations, is also discussed. An attractive alternative is to design starter cultures with carefully selected yeasts based on a detailed study of their interactions. It would allow reaching an acceptable use of the agave sugars obtaining mezcals with attractive organoleptic characteristics, produced in less time and at a lower cost. [ABSTRACT FROM AUTHOR]

Summary: The effect of initial storage temperature on the quality and safety characteristics of sardines was investigated. Initially, fresh sardines were stored in aerobic conditions at 0 °C, 5 °C or 10 °C for 24 h and subsequently, they were vacuum packed and stored at two distinct temperatures, namely 4 °C and 8 °C. Microbial growth, lipid oxidation (TBA values), pH, total volatile basic nitrogen (TVB‐N) and biogenic amines concentrations were monitored throughout storage. There were no notable differences in the pH levels of the different treatments, whereas higher TBA and TVBN values were observed for the sardines initially stored at higher temperatures. Significant differences (P < 0.05) in biogenic amine concentrations were observed throughout storage time. Samples exposed to lower initial temperatures exhibited longer lag times and lower production rates of biogenic amines. There were no statistically significant differences observed in microbial populations, although the sardine samples stored at 10 °C initially had the highest microbial populations. These results support the conclusion that initial handling conditions are important for the shelf‐life of fresh sardines and can drastically affect their overall quality and safety. [ABSTRACT FROM AUTHOR]

Microbes are associated inside and outside tissue parts of producers like plants, lichen, algae and phototrophic bacteria. Biofertilizer bacteria, fungi, algae and protozoa provide the suitable environment condition, nutrition constituents and inhibit harmful microorganism from rhizosphere zone. Biofertilizer and biocontrol microbes play key roles for improved soil texture, secreting, hormones, antibiotics and various stress signal compounds, enhancement plant parts elongation and prevent pathogen microbial population. Plant growth promotion rhizosphere microorganisms can improve crop tolerance for the non-living stresses such as drought, heat and salinity and living stress such as soil borne pathogens, over load of the microbial population liable to turn out to be more incessant as various atmosphere design keep on creating. Plant disease major issue for loss of productivity and unsafe for living organism due to chemical pesticides, insecticides, fungicides, bactericides and chemical fertilizer. Due to its high potential as an alternative/complement to these pesticides, biological disease control is now generally recognized and constitutes a low cost-efficient eco-friendly biofertilizer, biocontrol, biopesticide and bioinsecticide. [ABSTRACT FROM AUTHOR]

The motile micro-organisms such as Escherichia coli, sperm, or some seaweed are usually modeled by self-propelled particles that move with the run-and-tumble process. Individual-based stochastic models are usually employed to model the aggregation phenomenon at the boundary, which is an active research field that has attracted a lot of biologists and biophysicists. Self-propelled particles at the microscale have complex behaviors, while characteristics at the population level are more important for practical applications but rely on individual behaviors. Kinetic PDE models that describe the time evolution of the probability density distribution of the motile micro-organisms are widely used. However, how to impose the appropriate boundary conditions that take into account the boundary aggregation phenomena is rarely studied. In this paper, we propose the boundary conditions for a 2D confined run-and-tumble model (CRTM) for self-propelled particle populations moving between two parallel plates with a run-and-tumble process. The proposed model satisfies the relative entropy inequality and thus long-time convergence. We establish the relation between CRTM and the confined Fokker–Planck model (CFPM) studied in [J. Fu, B. Perthame and M. Tang, Fokker–Plank system for movement of micro-organism population in confined environment, J. Statist. Phys. 184 (2021) 1–25]. We prove theoretically that when the tumble is highly forward peaked and frequent enough, CRTM converges asymptotically to the CFPM. A numerical comparison of the CRTM with aggregation and CFPM is given. The time evolution of both the deterministic PDE model and individual-based stochastic simulations are displayed, which match each other well. [ABSTRACT FROM AUTHOR]

BACKGROUND: Traditional dry‐cured fermented sausages favour the growth of an autochthonous microbial population, which plays an important role in their sensory aspects. However, some moulds can produce mycotoxins such as ochratoxin A (OTA). The biocontrol agents (BCAs) Debaryomyces hansenii FHSCC 253H and Staphylococcus xylosus FHSCC Sx8 have been demonstrated to reduce OTA production in dry‐cured meat products, but their influence in the sensory characteristics of sausages has to be tested. The aim of this study was to evaluate the effect of these BCAs on the colour, texture and volatile profile of dry‐cured fermented sausages. RESULTS: D. hansenii caused few differences in the tested parameters with respect to the control batch. S. xylosus modified the texture and colour, although the values found were within the range expected for dry‐cured fermented sausages 'salchichón'. Additionally, the volatile profile revealed the potential antioxidant effect of both BCAs and their ability to produce compounds associated with the ripened aroma that could increase product acceptability. CONCLUSION: The results indicate that there were no inconveniences in implementing both BCAs during the processing of dry‐cured fermented sausages 'salchichón'. Moreover, D. hansenii FHSCC 253H could improve the volatile profile of this product. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This review aimed to analyze the effects of additives in producing silage from rehydrated corn grains for ruminants. The control treatment studies used in this analysis involved corn grain rehydrated with water only. To be included in the review, the studies needed to follow standardized criteria, including the absence of additives in the control treatment and the silage evaluation of the in animals such as cattle, goats, and sheep. A total of fifteen publications between 2014 and 2023 were included in the final dataset. The PROC ANOVA of SAS was used to compare the results, which included a random effect of comparison within the study, performing a paired comparison. It was observed that additives did not influence the chemical composition, pH, organic acid, ethanol content, microbial population, fermentative losses, aerobic stability, and dry matter in vitro digestibility of rehydrated corn grain silage (p > 0.05). Using additives in corn silage is a promising practice that can significantly benefit silage fermentation. Moisture silage additives mitigate high mycotoxin levels, enhance aerobic stability, improve cell wall digestibility, and increase the efficiency of utilization of silage nitrogen by ruminants. Using fermentation-stimulating additives (Lactobacillus buchneri) can improve the quality of rehydrated corn grain silage. There are still a few studies and more research to elucidate the best additives and the ideal amount to be added to ground corn grain silage. [ABSTRACT FROM AUTHOR]

The life of all creatures is supported directly or indirectly by soil, which is a significant environmental matrix. The soil has been polluted partly due to increased human activities and population growth, releasing several foreign substances and persistent contaminants. When toxic substances like polycyclic aromatic hydrocarbons (PAHs) are disposed of, the characteristics of the soil are changed, microbial biodiversity is impacted, and items are destroyed. Because of the mutagenicity, carcinogenicity, and toxicity of petroleum hydrocarbons, the restoration and cleanup of PAH-polluted areas represent a severe technological and environmental challenge for long-term growth and development. Although there are several ways to clean up PAH-contaminated soils, much attention is paid to intriguing bacteria, fungus, and their enzymes. Various factors influence PAH breakdown, including pH, temperature, airflow, moisture level, nutrient availability, and degrading microbial populations. This review discusses how PAHs affect soil characteristics and shows that secondary metabolite and carbon dioxide decomposition are produced due to microbial breakdown processes. Furthermore, the advantages of bioremediation strategies were assessed for correct evaluation and considered dependable on each legislative and scientific research level, as analyzed in this review. [ABSTRACT FROM AUTHOR]

The threat of environmental pollution in Nigeria, particularly in the Niger Delta region, cannot be solely ascribed to oil spillages; rather, it also encompasses the discharge of cassava mill effluent (CME), frequently disposed off in an unregulated manner. Existing studies on CME have focused on its potential environmental consequences on soil characteristics, microbial populations, and heavy metal levels. There is limited study on the awareness of the impact of CME on the environment. Thus, this study contributes to the literature on CME by examining the awareness of its effect on the environment in Ika North East Local Government Area of Delta State, Nigeria. The study used interviews, observation, and questionnaires administered to 399 respondents for data collection. A Student t-test, ANOVA, and Pearson's correlation were employed to analyse the data in Statistical Package for the Social Sciences. Results revealed limited awareness, with 51.3% unaware of CME's environmental impact. Slight, moderate, and extreme awareness were reported by 7.5%, 17.3%, and 23.8%, respectively. Gender's influence on awareness was insignificant, but age showed a significant influence (p < 0.05), while education, occupation, and income correlated positively with awareness (p < 0.001). The source of information significantly predicted awareness (r = −0.727, p < 0.001). It indicates that gender's influence on awareness might depend on education levels. Socio-economic factors are strongly related to awareness. Reliable information sources are vital for understanding CME's environmental impact. The study underscores the need for enhanced environmental education and reliable information dissemination to promote sustainable practices. [ABSTRACT FROM AUTHOR]

Coastal areas contain buildup of mixed organic and inorganic contaminants, which promote deterioration or sediment and impairment of benthic life. Hence, it is necessary to develop a method for sediment remediation and to promote the ecosystem. In this study, Granulated Coal Ash (GCA) was used as a covering material for the remediation of sediment. Our results indicate an increase in pH and oxidation–reduction potential, as well as a decrease in the concentrations of phosphate and hydrogen sulfide in the sediment and overlying water. The top three phyla observed based on 16S rRNA gene amplicon sequencing were Proteobacteria, Bacteroidetes, and Firmicutes. Further, as a consequence of physicochemical changes in the sediments, we observed a significant change in the relative abundance of Deltaproteobacteria, Epsilonproteobacteria, and Gammaproteobacteria. In conclusion, GCA is a promising covering material for limiting contaminants in sediment and overlying water, and promoting the diversity of microbial populations for sediment remediation. [ABSTRACT FROM AUTHOR]

The microbiota is essential for the extraction of energy and nutrition from plantbased diets and may have facilitated primate adaptation to new dietary niches in response to rapid environmental shifts. In this study, metagenomic sequencing technology was used to analyze the compositional structure and functional differences of the gut microbial community of Francois' langurs (Trachypithecus francoisi) under different environmental and dietary conditions. The results showed that in terms of the composition of the gut microbial community, there were significant differences among the gut microbiota of Francois' langurs (anthropogenic disturbed populations, wild populations, and captive populations) under different environmental and dietary conditions. The microbial communities with the highest abundance in Francois' langurs were Firmicutes and Bacteroidetes. Firmicutes was the most abundant phylum in anthropogenic disturbed Francois' langurs and the least abundant in captive Francois' langurs. The abundance of Bacteroidetes was highest in captive Francois' langurs. In the analysis and comparison of alpha diversity, the diversity of the gut microbiota of Francois' langurs affected by anthropogenic disturbance was the highest. The significant differences in gut microbiota between Francois' langurs in different environments and different diets were further supported by principal coordinate analysis (PCoA), with the disturbance group having a gut microbiota more similar to the wild group. Kyoto Encyclopedia of Genes and Genomes (KEGG) functional annotation analysis indicated a high abundance of functional genes involved in carbohydrate metabolism, amino acid metabolism, replication and repair, cofactor and vitamin metabolism, and other amino acid metabolism pathways. Additionally, the functional genes involved in carbohydrate metabolism pathways were significantly enriched in the gut microbial community of Francois' langurs that were anthropogenic disturbed and captive. The gut microbiota of the Francois' langurs exhibited potential plasticity for dietary flexibility, and longterm food availability in captive populations leads to changes in gut microbiota composition and function. This study explored the composition and function of the gut microbiota of Francois' langurs and provided a scientific basis for understanding the physiological and health status of Francois' langurs, effectively protecting the population of wild Francois' langurs and reintroducing captive Francois' langurs into the wild. [ABSTRACT FROM AUTHOR]

Soil bacterial and fungal communities were investigated in relation to soil type and farm management practices after vegetation harvesting in autumn. Soils from fields cultivated with Phaseolus vulgaris (bean) and Pyrus comminus (pear) and nonarable, natural areas were studied. Microbial diversity was analysed using cultivation-dependent methods (isolation of pure cultures) and cultivation-independent methods (direct extraction of DNA from soil, followed by PCR amplification of the 16S rRNA and 18S rRNA genes). The use of cultivation-dependent methods revealed that there were no differences in the biodiversity of the soil bacterial and fungal communities between fields cultivated with bean plants and pear trees. However, the use of cultivation-independent methods showed that there were clear soil and crop type-specific effects on the composition of the soil bacterial and fungal communities. The density of the bacterial population was two times higher in northern mountain-valley serozem (NMVS) soil samples than in light chestnut (LC) soil samples. In contrast, the densities of the fungal communities were almost equal in the studied soil types. The density of the actinomycetes community was almost two times higher in LC soil than in NMVS soil under bean plants. The Shannon index values showed that the bacterial biodiversity in the NMVS soil samples was greater than that in the LC soil samples. Soils under fallow appeared to have diverse bacterial communities that mainly consisted of local autochthonous microflora and a small amount of zymogenic microflora (since fresh plant residue does not enter the soil). The Shannon index results revealed two interesting facts: (1) the soil bacterial community was highly diverse in soils that supported bean plants and (2) the soil fungal biodiversity was high under pear trees in both soil types. [ABSTRACT FROM AUTHOR]

The extent and ecological significance of intraspecific functional diversity within marine microbial populations is still poorly understood, and it remains unclear if such strain-level microdiversity will affect fitness and persistence in a rapidly changing ocean environment. In this study, we cultured 11 sympatric strains of the ubiquitous marine picocyanobacterium Synechococcus isolated from a Narragansett Bay (RI) phytoplankton community thermal selection experiment. Thermal performance curves revealed selection at cool and warm temperatures had subdivided the initial population into thermotypes with pronounced differences in maximum growth temperatures. Curiously, the genomes of all 11 isolates were almost identical (average nucleotide identities of >99.99%, with >99% of the genome aligning) and no differences in gene content or single nucleotide variants were associated with either cool or warm temperature phenotypes. Despite a very high level of genomic similarity, sequenced epigenomes for two strains showed differences in methylation on genes associated with photosynthesis. These corresponded to measured differences in photophysiology, suggesting a potential pathway for future mechanistic research into thermal microdiversity. Our study demonstrates that present-day marine microbial populations can harbor cryptic but environmentally relevant thermotypes which may increase their resilience to future rising temperatures. [ABSTRACT FROM AUTHOR]