Microbial Metabolite Profiles Research Articles

Soil Microbial and Metabolomic Shifts Induced by Phosphate-Solubilizing Bacterial Inoculation in Torreya grandis Seedlings.

Phosphorus is crucial for plant growth and development, but excess fertilizer not absorbed by plants often binds with metal ions like iron and manganese, forming insoluble compounds that contribute to soil environmental pollution. This study investigates the impact of Burkholderia sp., a phosphate-solubilizing bacterium utilized as a biofertilizer, on the fertility of T. grandis soil, alongside the associated shifts in soil metabolites and their relationship with microbial communities after inoculation. The soil microbial community structures and metabolite profiles were analyzed via amplicon sequencing and high-resolution untargeted metabolomics. The inoculation of phosphate-solubilizing bacteria led to a significant (p < 0.05) enhancement in total phosphorus, potassium, and nitrogen concentrations in the soil, with a marked increase in available phosphorus in bulk soil (p < 0.05). Moreover, the microbial community structure exhibited significant shifts, particularly in the abundance of bacterial phyla such as Acidobacteria, Chloroflexi, Proteobacteria, and the fungal phylum Ascomycota. Metabolomic analysis revealed distinct metabolites, including fatty acids, hormones, amino acids, and drug-related compounds. Key microbial taxa such as Chloroflexi, Proteobacteria, Acidobacteria, Verrucomicrobia, Mucoromycota, and Ascomycota indirectly contributed to soil phosphorus metabolism by influencing these differential metabolites. In conclusion, the application of phosphate-solubilizing bacteria offers an innovative approach to improving soil quality in T. grandis, promoting phosphorus utilization efficiency, and enhancing soil ecosystem health by optimizing microbial communities and metabolite compositions.

Microbial community succession patterns and metabolite profiles in cigar tobacco during different mildew stages

Mildew in cigar tobacco leaves (CTLs) degrades both quality and market value. This research systematically examines dynamic changes in key metabolic compounds and microbial community succession throughout the mildew process, categorized into three stages: un-mildew (d0), early-mildew (d4 and d8), and late-mildew (d12 and d16). As mildew progresses, carbohydrates decrease, nitrogen metabolism is hindered, the carbon-nitrogen ratio (C/N) declines, and pH rises, making the tobacco weakly alkaline. The total amount of volatile flavor compounds (VFCs) increases, with the proportion of nitrogen-containing compounds such as nicotine rising, while neophytadiene, ketones, and alcohols decrease, leading to a disruption in the coordination of various aroma substances. Microbial diversity declines, with shifts in populations of Staphylococcus, Pseudomonas, Aspergillus, and Sampaiozyma. Six fungal and five bacterial genera are the characteristic dominate microorganisms at different stages. Co-occurrence network analysis shows that complexity decreases and stability declines, while microbial diversity peaks at the early-mold stage and is severely compromised at the late-mold stage in terms of stability and functional diversity. Two-way Orthogonal Partial Least Squares (O2PLS) identified 12 fungal and 3 bacterial genera as key drivers of metabolic changes. Partial Least Squares Structural Equation Modeling (PLS-SEM) emphasized the role of fungi in CTL degradation and the impact of C/N ratio on fungal metabolism. This study, for the first time, elucidates the complex relationship between microbial succession and metabolite compounds during mildew process, providing a reference for dynamic monitoring of fermented tobacco quality.

Predicting the Microbiome and Metabolome Dynamics of Natural Apple Fermentation Towards the Development of Enhanced Functional Vinegar

Natural vinegar fermentation is a complex process influenced by the interplay between microbial communities and metabolites. This study examined the interplay between the microbiome and the metabolome over a three-month period, with samples collected every ten days. Using Illumina sequencing and chromatographic techniques (HPLC and GC-MS), we mapped microbial shifts and metabolite profiles. Early fermentation showed a diverse microbial presence, including genera such as Cronobacter, Luteibacter, and Saccharomyces. A stable microbial ecosystem established between days 15 and 70, characterized by the dominance of Leuconostoc, Gluconobacter, and Saccharomyces, which facilitated consistent substrate consumption and metabolite production, including various organic acids and ethanol. By day 70, Acetobacter prevalence increased significantly, correlating with a peak acetic acid production of 12.4 g/L. Correlation analyses revealed significant relationships between specific microbes and volatile organic compounds. This study highlights the crucial roles of these microbes in developing sensory profiles suited for industrial applications and proposes an optimal microbial consortium for enhancing vinegar quality. These data suggest that an optimal microbial consortium for vinegar fermentation should include Saccharomyces for efficient alcohol production, Leuconostoc for ester-mediated flavor complexity, and Acetobacter for robust acetic acid production. The presence of Komagataeibacter could further improve the sensory and functional qualities due to its role in producing bacterial cellulose.

Microbial Dynamics and Pathogen Control During Fermentation of Distiller Grains: Effects of Fermentation Time on Feed Safety.

Determining the effects of fermentation duration on the microbial ecosystem, potential pathogenic risks, and metabolite generation during the fermentation of distilled grains is essential for safeguarding the safety and enhancing the nutritional profile of animal feed. This study investigates the effect of varying fermentation times (9, 30, and 60 days) on microbial diversity, pathogenic risk, and metabolite profiles in distiller grains using 16S rDNA sequencing and LC-MS-based metabolomics. The results showed that early fermentation (9-30 days) enhanced the abundance of beneficial bacteria, such as Lactobacillus reuteri and Lactobacillus pontis (p < 0.05), while pathogenic bacteria, like Serratia marcescens and Citrobacter freundii, were significantly reduced (p < 0.05). Metabolomic analysis revealed an increase in unsaturated fatty acids and the degradation of biogenic amines during early fermentation. However, prolonged fermentation (60 days) led to a resurgence of pathogenic bacteria and reduced the synthesis of essential metabolites. These findings suggest that fermentation duration must be optimized to balance microbial safety and nutrient quality, with 30 days being the optimal period to reduce pathogenic risks and enhance feed quality.

Effect of Microgravity on Rare Earth Elements Recovery by Burkholderia cepacia and Aspergillus niger

Rare earth elements (REEs) are indispensable in modern industry and technology, driving an urgent demand for innovative, eco-friendly recovery technologies. As space exploration advances, the impact of microgravity on microorganisms has become a focal point, yet the effects on microbial growth and REEss recovery remain uncharted. This study investigates the biosorption of REEs by Burkholderia cepacia (B. cepacia) and Aspergillus niger (A. niger) from a mixed solution containing La, Ce, Pr, Nd, Sm, Er, and Y under varying initial concentrations, pH levels, and microgravity conditions. We observed that the medium’s pH rose with B. cepacia and fell with A. niger when cultured in normal gravity conditions, suggesting distinct metabolic responses. Notably, microgravity significantly altered microbial morphology and metabolite profiles, significantly enhancing REEs recovery efficiency. Specifically, the recovery of B. cepacia of Ce and Pr peaked at 100%, and A. niger achieved full recovery of all tested REEs at pH 1.5 (suboptimal growth conditions). This study pioneers the application of biosorption for the recovery of REEs in microgravity conditions, presenting a promising strategy for future resource exploitation by space biomining.

Microbial Protein and Metabolite Profiles of Klebsiella oxytoca M5A1 in a Bubble Column Bioreactor.

The production of microbial proteins (MPs) has emerged as a critical focus in biotechnology, driven by the need for sustainable and scalable alternatives to traditional protein sources. This study investigates the efficacy of two experimental setups in producing MPs using the nitrogen-fixing bacterium Klebsiella oxytoca M5A1. K. oxytoca M5A1, known for its facultative anaerobic growth and capability to fix atmospheric nitrogen, offers a promising avenue for environmentally friendly protein production. This research compares the performance of a simple bubble column (BC) bioreactor, which promotes efficient mixing and cross-membrane gas transfer, with static fermentation, a traditional method lacking agitation and aeration. The study involved the parallel cultivation of K. oxytoca M5A1 in both systems, with key parameters such as microbial growth, glucose utilization, protein concentration, and metabolite profiles monitored over a 48 h period. The results indicate that the BC bioreactor consistently outperformed static fermentation regarding the growth rate, protein yield, and glucose utilization efficiency. The BC exhibited a significant increase in protein production, reaching 299.90 µg/mL at 48 h, compared to 219.44 µg/mL in static fermentation. The organic acid profile reveals both synthesis and utilization regimes of varying patterns. These findings highlight the advantages of the BC bioreactor for MP production, particularly its ability to maintain aerobic conditions that support higher growth and yield.

Novel mechanistic understanding that Lactiplantibacillus plantarum is more capable of improving the ensiling performance of wheat straw silage than xylanase by driving certain key metabolites

Microbial and enzyme additives can improve silage performance, but there is limited comparative research on the effects of microbial and enzyme additives on improving silage fermentation quality, and the underlying microbial and metabolic pathways remain unclear. This study investigated the effects without inoculants (CK treatment) or with Lactiplantibacillus plantarum (LP treatment), xylanase (XY treatment) and their combination (LPXY treatment) on the fermentation quality, as well as on the microbial communities and metabolite profiles of the wheat straw silage. The results demonstrated that the LP treatment has a better effect on improving the fermentation quality of wheat straw silage compared to other treatments, as evidenced by markedly (p < 0.05) decreased the pH (4.06), acid and neutral fiber (ANF, NDF, 23.43 and 31.69%DM), and increased the lactic acid (LA, 965.89 mg/L) and acetic acid (AA, 656.10 mg/L) concentrations. After the fermentation process, the LP treatment significantly (p < 0.05) enhanced the abundance of Lactobacillus, reduced bacterial Shannon (p < 0.05) and increased some key metabolites content. The structural equation models (SEMs) and Pearson’s correlation results proved that the LP treatment improved the wheat straw silage fermentation quality via increasing the abundance of Lactobacillus, decreasing the diversity of bacterial community and enriching the content of certain key metabolites. The present study provides mechanistic evidence that Lactiplantibacillus plantarum additive is superior to xylanase additive and their combination on improving fermentation quality of wheat straw silage, that is, by enriching certain key metabolites to increase AA and LA concentrations, providing a reference for the cross study of silage feed fermentation microbiome and metabolome.Graphical

Intercropping of tobacco and maize at seedling stage promotes crop growth through manipulating rhizosphere microenvironment.

Changes in the rhizosphere microbiome and metabolites resulting from crop intercropping can significantly enhance crop growth. While there has been an increasing number of studies on various crop combinations, research on the intercropping of tobacco and maize at seedling stage remains limited. This study is the first to explore rhizosphere effects of intercropping between tobacco and maize seedling stages, we analyzed the nitrogen, phosphorus and potassium nutrients in the soil, and revealed the important effects on soil microbial community composition and metabolite profiles, thereby regulating crop growth and improving soil balance. Compared with mono-cropping, intercropping increased the biomass of the two crops and promoted the nutrient absorption of nitrogen, phosphorus and potassium. Under intercropping conditions, the activities of sucrase, catalase and nitrate reductase in tobacco rhizosphere soil and the content of available potassium, the activities of nitrate reductase and acid phosphatase in maize rhizosphere soil were significantly increasing. Rhizosphere soil bacterial and fungal communities such as Sphingomonas, Massilia, Humicola and Penicillium respond differently to crop planting patterns, and soil dominant microbial communities are regulated by environmental factors such as pH, Organic Matter, Available Potassium, Nitrate Reductase, and Urease Enzyme. Network analysis showed that soil microbial communities were more complex after intercropping, and the reciprocal relationship between bacteria and fungi was enhanced. The difference of metabolites in soil between intercropping and monocropping system was mainly concentrated in galactose metabolism, starch and sucrose metabolism pathway, and the content of carbohydrate metabolites was significantly higher than that of monocropping soil. Key metabolites such as D-Sucrose, D-Fructose-6-Phosphate, D-Glucose-1-Phosphatel significantly influence the composition of dominant microbial communities such as Sphingomonas and Penicillium. This study explained the effects of intercropping between flue-cured tobacco and maize on the content of soil metabolites and soil microbial composition in rhizosphere soil, and deepened the understanding that intercropping system can improve the growth of flue-cured crops seedlings through rhizosphere effects.

Disordered Gut Microbiome and Alterations in Metabolic Patterns Are Associated With Hypertensive Left Ventricular Hypertrophy.

Left ventricular hypertrophy (LVH) is most common when driven by hypertension, and it is a strong independent risk factor for adverse cardiovascular events and death. Some animal models support a role for gut microbiota and metabolites in the development of LVH, but cohort studies confirming these findings in populations are lacking. We investigated the alterations of gut microbiota and metabolites in 30 patients with hypertension, 30 patients with hypertensive LVH, and 30 matched controls on the basis of 16S rDNA and metabolomic analyses. Thirty stool and 90 serum samples were collected in fasting conditions. ANOVA/Kruskal-Wallis/Pearson's χ2/Fisher's exact test and Bonferroni's correction were used (P<0.0167) for comparison among the 3 groups. A regression analysis and subgroup analysis were performed between gut microbiota and left ventricular mass index (LVMI) and metabolites and LVMI, respectively. Spearman correlation analysis was performed between metabolites and flora and metabolites and LVMI. We observed LVH-enriched Faecalitalea (β=6758.55 [95% CI, 2080.92-11436.18]; P=0.009), Turicibacter (β=8424.76 [95% CI, 2494.05-14355.47]; P=0.01), Ruminococcus torques group (β=840.88 [95% CI, 223.1-1458.67]; P=0.013), and Erysipelotrichaceae UCG-003 (β=856.37 [95% CI, 182.76-1529.98]; P=0.019) were positively correlated with LVMI. A total of 1141 (in sera) and 2657 (in feces) metabolites were identified. There was a sex-specific association between metabolites and LVMI. Significant changes in metabolic pathways in LVH were also observed, especially bile acid and lipid metabolism pathways. Our study demonstrated the disordered gut microbiota and microbial metabolite profiles in LVH. This highlights the roles of gut bacteria and metabolite in this disease and could lead to new intervention, diagnostic, or management paradigms for LVH. URL: https://www.chictr.org.cn; Unique Identifier: ChiCTR2200055603.

Exploring the Fermentation Products, Microbiology Communities, and Metabolites of Big-Bale Alfalfa Silage Prepared with/without Molasses and Lactobacillus rhamnosus

The influence of molasses (M) and Lactobacillus rhamnosus (LR) on fermentation products, microbial communities, and metabolites in big-bale alfalfa silage was investigated. Alfalfa (Medicago sativa L.) was harvested at the third growth stage during the flowering stage in the experimental field of Linhui Grass Company from Tongliao City, Inner Mongolia. An alfalfa sample without additives was used as a control (C). M (20 g/kg) and LR (106 cfu/g) were added either alone or in combination. Alfalfa was fermented for 7, 14, and 56 d. Lactic acid content in the M, LR, and MLR groups increased, whereas the pH value and butyric acid, 2,3-butanediol, and ethanol contents decreased compared to those of C group after 7, 14, and 56 d of fermentation. A two-way analysis of variance (ANOVA) was performed to estimate the results. The LR group exhibited increased Lactobacillus abundance, whereas the M and MLR groups showed increased Weissella abundance compared to the C group. The relative contents of amino acids (tyrosine, isoleucine, threonine, arginine, valine, and citrulline) in the M and MLR groups were higher than those in the C group. During fermentation, the M, LR, and MLR groups showed decreased phenylalanine, isoleucine, and ferulic acid contents. Amino acids such as isoleucine and L-aspartic acid were positively correlated with Lactobacillus but negatively correlated with Weissella. In conclusion, combining high-throughput sequencing and liquid chromatography–mass spectrometry during anaerobic alfalfa fermentation can reveal new microbial community compositions and metabolite profiles, supporting the application of M, LR, and MLR as feed fermentation agents.

Metagenomic and metabolite analysis reveals microbial community and metabolite dynamics in fermented Indigo naturalis

The soaking and fermentation of the stems and leaves is an important intermediate step in the processing of Indigo Naturalis. However, the relationship between microbiota and Indigo Naturalis yields is still poorly understood. This study aimed to compare microbial communities and metabolite profiles at various stages of soaking fermentation, followed by validation of the results using HPLC. A total of 731 compounds were identified through metabolite analysis, with the levels of indigo and indirubin peaking after 36 h of fermentation. Metagenomes revealed Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria were identified as the most abundant microbial phyla in soaking fermentation. Correlation analysis indicated that the yields of indigo and indirubin may be affected by Lactococcus, Clostridium, and Enterobacter through the regulation of related synthetic enzymes. The findings offered novel perspectives on the relationship of microorganisms and Indigo Naturalis yields.

16S metagenomics and metabolomics unveil the microbial compositions and metabolite profiles in Dahi, a traditional Indian fermented milk product prepared by the backslopping method

16S metagenomics and metabolomics unveil the microbial compositions and metabolite profiles in Dahi, a traditional Indian fermented milk product prepared by the backslopping method

Microbial Dynamics and Metabolite Profiles in Different Types of Salted Seafood (Jeotgal) During Fermentation.

Salted and fermented seafood (jeotgal) is known for its long shelf life and unique flavor. Despite the existence of various types of salted seafood, the factors influencing this quality have yet to be identified. These factors are essential for improving the quality of salted seafood, optimizing the fermentation process, and advancing the industrialization of fermented foods. Therefore, in this study, we explored microbial dynamics and changes in quality characteristics in three salted seafood items - salted anchovies (MJ), salted cutlass offal (GJ), and salted croakers (HJ), over a 24-month fermentation period. Distinct microbial community profiles, dominated by Tetragenococcus halophilus, Halanaerobium fermentans, and Chromohalobacter canadensis in MJ, GJ, and HJ, respectively, affect the metabolic pathways and the corresponding flavor profiles. The pH of all samples ranged from 5.7-6.0. The titratable acidity was highest in MJ at 1.4% and lowest in HJ at approximately 0.7%. Salinity was below 25% in all samples but slightly lower in MJ. Significant differences were observed in the amino acid, nucleotide, and overall metabolite profiles. MJ exhibited the highest amino acid and nitrogen-related factor levels, such as glutamic acid and hypoxanthine, enhancing flavor complexity. Correlation analysis revealed significant associations among the types, metabolites, and microbial communities. Microbial survival mechanisms in high-salt environments result in the production of unique metabolites, including umami and aroma components as well as precursors of biogenic amines, which can affect the overall quality of the final product. These differences were primarily influenced by the fish type rather than the fermentation time. Our findings provide foundational insights for enhancing fermentation strategies, improving product consistency, and advancing the industrial application of microbial management in seafood fermentation. This study not only fills a significant gap in the current understanding of fermented seafood but also outlines practical approaches for industry applications for the optimization of product quality.

Fuzi lizhong pills alter microbial community compositions and metabolite profiles in ulcerative colitis rat with spleen-kidney yang deficiency syndrome

Ethnopharmacological relevanceUlcerative colitis (UC) is a chronic inflammatory bowel condition that is frequently related with Spleen-Kidney Yang Deficiency Syndrome (SKYD) in Chinese medicine. Fuzi Lizhong Pill (FLZP), a traditional medicine for SKYD, has been utilized in China for generations, although the exact mechanism by which it treats UC is unknown. Aim of the studyThe goal of this study is to further understand FLZP's therapeutic mechanism in SKYD-associated UC. Materials and methodsTo investigate the impact of FLZP on SKYD-associated UC, we used a comprehensive method that included serum metabolomics and gut microbiota profiling. The chemical composition of FLZP was determined using mass spectrometry. UC rats with SKYD were induced and treated with FLZP. Serum metabolomics and 16S rRNA microbial community analysis were used to evaluate FLZP's effects on endogenous metabolites and gut microbiota, respectively. Correlation analysis investigated the association between metabolites and intestinal flora. A metabolic pathway analysis was undertaken to discover putative FLZP action mechanisms. ResultsFLZP contains 109 components, including liquiritin (584.8176 μg/g), benzoylaconine (16.3087 μg/g), benzoylhypaconine (31.9583), and hypaconitine (8.1160 μg/g). FLZP predominantly regulated seven metabolites and eight metabolic pathways involved in amino acid and nucleotide metabolism, with an emphasis on energy metabolism and gastrointestinal digestion. FLZP also influenced intestinal flora variety, increasing probiotic abundance while decreasing pathogenic bacteria prevalence. An integrated investigation identified associations between changes in certain gut flora and energy metabolism, specifically the tricarboxylic acid (TCA) cycle. ConclusionsFLZP successfully cures UC in SKYD rats by regulating amino acid and energy metabolism. Its positive effects may include altering microbiota composition and metabolite profiles in UC rats with SKYD. These findings shed light on FLZP's mode of action and its implications for UC management.

Chloroquine Downregulation of Intestinal Autophagy Changed Intestinal Microbial Community Compositions and Metabolite Profiles in Piglets.

Our previous study demonstrated that moderate inhibition of intestinal autophagy was beneficial to alleviate early weaning stress in piglets, but the detailed mechanism behind this was unclear. Microbiota-mediated enterocyte autophagy helps maintain intestinal homeostasis. This study investigated the effects of inhibition or activation of autophagy in intestinal microbial community compositions and metabolite profiles in piglets. Eighteen 24-day-old weaned piglets were divided into three groups (each treatment of six piglets) and treated daily with rapamycin (RAPA), chloroquine (CQ) or a control volume of normal saline (CON group). Before the formal trial, the piglets were allowed to acclimatize for 3 days, and then the trial period was 14 days. Collected samples from the ileum and colon underwent 16S rRNA gene sequencing and metabolite analysis. Significant differences in microbial composition were observed in both the ileum and colon of the RAPA and CQ groups compared to the CON group (p < 0.05). In addition, the relative levels of abundance of Peptostreptococcus, Fusobacterium, Dialister, Selenomonas and Oceanobacillus in the ileum and Porphyromonas, Bacteroides, unidentified_Lachnospiraceae, Akkermansia, Sharpea, Peptococcus, Pseudoalteromonas, Peptoclostridium and unidentified_Acidobacteria in the colon were improved in piglets fed the RAPA diet, whereas the relative levels of abundance of Turicibacter, Rickettsiella and Sarcina in the ileum and Roseburia and Kroppenstedtia in the colon were enhanced in the CQ group (p < 0.05). Meanwhile, metabolomic analysis showed that there were significant differences in metabolites among all groups (p < 0.05), and KEGG enrichment analysis revealed that differential metabolites were mainly enriched in the ABC transporters and biosynthesis of amino acids pathways. Furthermore, these metabolites were closely related to differential microorganisms (p < 0.05). Overall, autophagy inhibition regulates the composition of intestinal microorganisms and their metabolites, and these differential metabolites are significantly correlated with differential intestinal microorganisms, which may in turn affect the production performance of weaned piglets.

Microbiomic and metabolomic dynamics in chrysanthemum waste at different fermentation stages

The microbial community and metabolite profile during the fermentation of chrysanthemum waste (CW) were studied, as well as the effect of feeding fermented chrysanthemum waste (FCW) to sows. The nutritional value of CW fermented for 30–90 days was similar to that of CW fermented for 7 days. With increasing time, the number of bacterial species, richness index, and diversity index increased. The main genera were Pediococcus. A total of 270 different metabolites were identified in FCW, among which benzenoids, amino acids, flavonoids, fatty acids, and peptides were the most significantly different metabolites. Flavone and flavonol biosynthesis, and flavonoid biosynthesis were the most important metabolic pathways in fermentation. Feeding FCW to sows was beneficial for their production performance. These provide new insights into the characteristics of microbiome and metabolome associated with CW during long-term fermentation and the feed availability of FCW.

Lactiplantibacillus plantarum causes the abnormal fermentation of bacterial cellulose by Komagataeibacter nataicola during nata de coco production

Nata de coco, chemically known as bacterial cellulose (BC), is mostly manufactured in Southeast Asian countries and Hainan, China. Failures happened frequently due to the open fermentation system of nata de coco, especially in winter and spring. This study investigated the differences between normal and abnormal fermentation processes in a nata de coco manufacturing factory. Results revealed significant variations in microbial composition and metabolite profiles between abnormal and normal fermentation batches. Lactiplantibacillus plantarum GPb4103 was further isolated and screened from the abnormal fermentation broth to investigate its potential inhibitory effect on BC synthesis of Komagataeibacter nataicola JY6211. Although co-culturing the strain JY6211 and L. plantarum GPb4103 resulted in synergistic growth, BC yield decreased by up to 53%. The KEGG pathway analysis of differential metabolites showed that the GPb4103 hindered BC synthesis of the JY6211 by altering accumulation of metabolites in the fermentation broth through metabolic pathways. This study provides new insights into how specific microbes could affect BC synthesis of K. nataicola during nata de coco production, thereby illuminating challenges faced in commercial BC production, such as inconsistent products quality and problematic production processes.

Effects of slightly acidic electrolyzed water on safety, antioxidant activity, and metabolite profile of buckwheat sprouts (Fagopyrum spp.)

The effect of slightly acidic electrolyzed water (SAEW) on the microbial load, metabolite profile, antioxidant, and growth of germinated buckwheat was investigated. All the SAEW solutions exhibited antimicrobial activity with no adverse impact on buckwheat sprouts' growth. The SAEW 30 ppm (pH = 5.0)-treated sprouts displayed highest 84.10 mg/g total phenolic content on the 5th day. Similarly, a notable increase in rutin content occurred from 4th day, and by the 5th day, it was highest at 43.73 mg/g. Moreover, using SAEW (pH = 5.0 and 6.5) increased the concentration of quercetin to 5.61 and 5.42 mg/g, respectively. UHPLC-QTOF-MS/MS identified numerous compounds, predominantly amino, acids, fatty acids, polyphenols, and organic acid; the levels of which were strongly improved by SAEW (pH = 5.0). It was consistently observed that buckwheat sprouts treated with SAEW (pH = 5.0) exhibited the highest DPPH-reducing capability compared to all other treatment groups, especially on the 5th day. Similarly, SAEW (pH = 5.0)-germinated sprouts demonstrated the highest ABTS scavenging activity at 94.38%, followed by SAEW at 6.5 (87.22%), for germinated seeds on the 5th day. Therefore, buckwheat sprouts elicited with SAEW and harvested on the 5th day could demonstrate an enhanced bioactive profile and health-promoting benefits.

Differential effects of pectin-based dietary fibre type and gut microbiota composition on in vitro fermentation outcomes

Interactions between human gut microbiota and dietary fibres (DF) are influenced by the complexity and diversity of both individual microbiota and sources of DF. Based on 480 in vitro fermentations, a full factorial experiment was performed with six faecal inocula representing two enterotypes and three DF sources with nanometer, micrometer, and millimeter length-scales (apple pectin, apple cell walls and apple particles) at two concentrations. Increasing DF size reduced substrate disappearance and fermentation rates but not biomass growth. Concentrated DF enhanced butyrate production and lactate cross-feeding. Enterotype differentiated final microbial compositions but not biomass or fermentation metabolite profiles. Individual donor microbiota differences did not influence DF type or concentration effects but were manifested in the promotion of different functional microbes within each population with the capacity to degrade the DF substrates. Overall, consistent effects (independent of donor microbiota variation) of DF type and concentration on kinetics of substrate degradation, microbial biomass production, gas kinetics and metabolite profiles were found, which can form the basis for informed design of DF for desired rates/sites and consequences of gut fermentation. These results add further evidence to the concept that, despite variations between individuals, the human gut microbiota represents a community with conserved emergent properties.

Long-Term Disinfection in Operating Rooms Affects Skin Microbiota and Metabolites of Medical Personnel

Introduction: Disinfectants play a critical role in reducing healthcare-associated infections by eliminating microorganisms on surfaces. However, prolonged use of disinfectants may adversely affect the skin microflora, essential for skin health and infection prevention. This study investigates the impact of disinfection on the skin microbiota and metabolites of medical personnel in operating rooms, aiming to provide a scientific foundation for safeguarding their skin health. Methods: We conducted 16S sequencing and metabolomic analysis to assess the effects of disinfection on the skin microbiota and metabolites of medical personnel. Samples were collected from operating room personnel after disinfectant exposure to identify changes in microbial communities and metabolite profiles. Results: Our analysis revealed that prolonged use of disinfectants led to alterations in skin microbial communities and microbial metabolites. These alterations included the production of harmful metabolites that could potentially promote skin infections and other health issues among medical personnel. Conclusion: The findings underscore the importance of minimizing disruptions to skin microbiota and metabolites caused by long-term disinfectant use to preserve the overall health of medical personnel. This study provides valuable insights into the relationship between disinfectant use, skin microbiota, and metabolites, highlighting the necessity for further research in this area.