Butyric Acid Production Research Articles

Effect of burdock on the regulation of gut microbiota in hyperglycemic rats and its in vitro digestion and fermentation characteristics

Burdock has previously been reported to have anti-diabetic effect. Gut microbiota is an important indicator of diabetes. This study investigated the effect of burdock root powder on the diversity and composition of gut microbiota in hyperglycemic rats. Moreover, the nutritional content, biological activities and beneficial metabolites production of burdock powder during in vitro digestion are determined to supplement its anti-diabetic effect. Our results showed that burdock powder improved intestinal flora diversity in diabetic rats significantly (p < 0.05). Abundance of Lactobacillales, Firmicutes, Peptostreptococcales-Tissierellales, Peptostreptococcaceae, Enterococcaceae and Romboutsia was increased. The abundance of Erysipelotrichales and Turicibacter decreased. Inhibitory activities of α-glucosidase and α-amylase of burdock reached the highest at intestinal and gastric digestion stages (p < 0.05), respectively. Burdock can regulate the intestinal flora of hyperglycemic rats, prompting the production of acetic acid and butyric acid in their feces.

Dilution rates and their transition modes influence organic acid productivity and bacterial community structure on continuous meta-fermentation using complex microorganisms

We investigated the effect of dilution rates (D) (0.05, 0.15, and 0.4h-1) and its transition mode strategies (constant, up, and down modes) on organic acid productivity and bacterial community structure on continuous meta-fermentation using complex microorganisms. The number of bacterial species decreased with increasing D in the constant mode while up and down modes maintained high and low values, respectively, regardless of the changing D values. Caldibacillus hisashii was the predominant species in all modes at all D values, while other bacterial species, including Anaerosalibacter bizertensis and Clostridium cochlearium were predominant in only certain modes and D values. The highest total organic acid productivity of 3.16gL-1h-1 was obtained with 82.2% lactic acid selectivity at D=0.4h⁻1 in constant mode. Heterofermentation occurred in the up mode, while the down mode exhibited the maximum butyric acid productivity of 0.348gL-1h-1 with 43.8% selectivity at D=0.05h-1. The constant, up, and down modes showed the distinct main products of lactic, acetic and formic, and butyric acids, respectively. In this study, we proposed a new parameter of species-specific productivity (SSP) to estimate which species and how much a bacterium quantitatively contributes to the targeted organic acid productivity in continuous meta-fermentation. SSP was determined based on the abundance of functional genes encoding key enzymes from the results of 16S amplicon analysis. In conclusion, D values and their transition modes affect productivity by changing the bacterial community structure, and are a significant factor in establishing a highly productive process in continuous meta-fermentation.

Impact of galacto-oligosaccharides on prebiotic potential in the intestinal microbiota fermentation and health status in an animal model

The present study was conducted to assess selected galacto-oligosaccharides (GOS) effects on short-chain acids (SCFA), microbiota variability in in vitro, and health benefits using an animal model. In the in-vitro anaerobic batch, fermentation was applied to different groups divided by a varied amount of GOS sources, mixtures, and prebiotics. Results reported that SCFA for inulin contributed significantly higher for acetic, propionic, and butyric acids, and resistant starch (RS) showed a non-significant effect for acetic and propionic acids whereas the combined effect of GOS and RS showed higher values for parameters. For bacterial enumeration of bifidobacteria compared to individual GOS, synergistic effects were documented. The Sprague-Dawley rats given GOS under western diet influence relative to a high-fat diet alone observed after 1 and 4 weeks documented significant levels for acetic and butyric acid production, whereas body and organ weights for cecum tend to increase after 4 weeks of dietary intervention (p&lt;0.05). Microbiome data using gene sequencing revealed a higher proportion of firmicutes and lower Bacteroides in control rats, which means Lachnospiraceae family abundances were higher in HF+GOS group. Overall, GOS fermentation showed an increment in the bifidobacterial population and tend to raise levels of SCFA in rats fed on a high-fat diet alone, whereas non-significant variation was reported in microbiome diversity after intervention.&#x0D; The present study was conducted to assess selected galacto-oligosaccharides (GOS) effects on short-chain acids (SCFA), microbiota variability in in vitro, and health benefits using an animal model. In the in-vitro anaerobic batch, fermentation was applied to different groups divided by a varied amount of GOS sources, mixtures, and prebiotics. Results reported that SCFA for inulin contributed significantly higher for acetic, propionic, and butyric acids, and resistant starch (RS) showed a non-significant effect for acetic and propionic acids whereas the combined effect of GOS and RS showed higher values for parameters. For bacterial enumeration of bifidobacteria compared to individual GOS, synergistic effects were documented. The Sprague-Dawley rats given GOS under western diet influence relative to a high-fat diet alone observed after 1 and 4 weeks documented significant levels for acetic and butyric acid production, whereas body and organ weights for cecum tend to increase after 4 weeks of dietary intervention (p&lt;0.05). Microbiome data using gene sequencing revealed a higher proportion of firmicutes and lower Bacteroides in control rats, which means Lachnospiraceae family abundances were higher in HF+GOS group. Overall, GOS fermentation showed an increment in the bifidobacterial population and tend to raise levels of SCFA in rats fed on a high-fat diet alone, whereas non-significant variation was reported in microbiome diversity after intervention.

Cassava Foliage Effects on Antioxidant Capacity, Growth, Immunity, and Ruminal Microbial Metabolism in Hainan Black Goats.

Cassava (Manihot esculenta Crantz) foliage is a byproduct of cassava production characterized by high biomass and nutrient content. In this study, we investigated the effects of cassava foliage on antioxidant capacity, growth performance, and immunity status in goats, as well as rumen fermentation and microbial metabolism. Twenty-five Hainan black goats were randomly divided into five groups (n = 5 per group) and accepted five treatments: 0% (T1), 25% (T2), 50% (T3), 75% (T4), and 100% (T5) of the cassava foliage silage replaced king grass, respectively. The feeding experiment lasted for 70 d (including 10 d adaptation period and 60 d treatment period). Feeding a diet containing 50% cassava foliage resulted in beneficial effects for goat growth and health, as reflected by the higher average daily feed intake (ADFI), average daily gain (ADG) and better feed conversion rate (FCR), as well as by the reduced serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine (CRE), and triglycerides (TG). Meanwhile, cassava foliage improved antioxidant activity by increasing the level of glutathion peroxidase (GSH-Px), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC) and lowering malondialdehyde (MDA). Moreover, feeding cassava foliage was also beneficial to immunity status by enhancing complement 3 (C3), complement 4 (C4), immunoglobulin A (IgA), immunoglobulin G (IgG), and immunoglobulin M (IgM). Furthermore, the addition of dietary cassava foliage also altered rumen fermentation, rumen bacterial community composition, and metabolism. The abundance of Butyrivibrio_2 and Prevotella_1 was elevated, as were the concentrations of beneficial metabolites such as butyric acid; there was a concomitant decline in metabolites that hindered nutrient metabolism and harmed host health. In summary, goats fed a diet containing 50% cassava foliage silage demonstrated a greater abundance of Butyrivibrio_2, which enhanced the production of butyric acid; these changes led to greater antioxidant capacity, growth performance, and immunity in the goats.

Gum Arabic/Chitosan Coacervates for Encapsulation and Protection of Lacticaseibacillus rhamnosus in Storage and Gastrointestinal Environments.

Probiotics, such as Lacticaseibacillus rhamnosus, are essential to the food industry for their health benefits to the host. The Lcb. rhamnosus strain is susceptible to processing, gastrointestinal, and storage conditions. In this study, Lcb. rhamnosus strains were encapsulated by complex coacervation in a gum arabic/chitosan or gum arabic/trehalose/chitosan and cross-linked with sodium tripolyphosphate. The physicochemical properties (zeta potential, water activity, water content, and hygroscopicity), encapsulation efficiency, and probiotic survival under storage conditions and simulated gastrointestinal fluids were evaluated. The results showed that crosslinking improves the encapsulation efficiency after drying; however, this result was remarkable when trehalose was used as a cryoprotectant. Furthermore, the encapsulation matrix preserved the viability of probiotics during 12weeks with probiotic counts between 8.7-9.5, 7.5-9.0, and 5.2-7.4 log10 CFU g-1 at -20, 4, and 20°C, respectively. After 12days of digestion in an ex vivo simulator, acetic, butyric, propionic, and lactic acid production changed significantly, compared to free probiotic samples. This work shows that encapsulation by complex coacervation can promote the stability of probiotic bacteria in storage conditions and improve the viability of Lcb. rhamnosus HN001 during consumption so that they can exert their beneficial action in the organism.

Steerable isobutyric and butyric acid production from CO2 and H2 by Clostridium luticellarii.

Clostridium luticellarii is a recently discovered acetogen that is uniquely capable of producing butyric and isobutyric acid from various substrates (e.g. methanol), but it is unclear which factors influence its (iso)butyric acid production from H2 and CO2 . We aimed to investigate the autotrophic metabolism of C. luticellarii by identifying the necessary growth conditions and examining the effects of pH and metabolite levels on product titers and selectivity. Results show that autotrophic growth of C. luticellarii requires the addition of complex nutrient sources and the absence of shaking conditions. Further experiments combined with thermodynamic calculations identified pH as a key parameter governing the direction of metabolic fluxes. At circumneutral pH (~6.5), acetic acid is the sole metabolic end product but C. luticellarii possesses the unique ability to co-oxidize organic acids such as valeric acid under high H2 partial pressures (>1 bar). Conversely, mildly acidic pH (≤5.5) stimulates the production of butyric and isobutyric acid while partly halting the oxidation of organic acids. Additionally, elevated acetic acid concentrations stimulated butyric and isobutyric acid production up to a combined selectivity of 53 ± 3%. Finally, our results suggest that isobutyric acid is produced by a reversible isomerization of butyric acid, but valeric and caproic acid are not isomerized. These combined insights can inform future efforts to optimize and scale-up the production of valuable chemicals from CO2 using C. luticellarii.

Isolation and characterization of Enterococcus faecalis isolate VT-H1: A highly efficient hydrogen-producing bacterium from palm oil mill effluent (POME)

Facultative hydrogen-producing bacteria hold immense potential for fermentative hydrogen and valuable metabolite production. In this study, a mesophilic hydrogen-producing bacterium was isolated from palm oil mill effluent (POME) and identified as Enterococcus faecalis isolate VT-H1 using hybrid sequencing technologies. Our investigation encompassed the growth of the isolate and its capacity for hydrogen and volatile fatty acid (VFA) production. The results revealed that optimal growth occurred when glucose was utilized at 37 °C and initial pH of 7.0, resulting in a final OD600 of 2.58. The isolate demonstrated exceptional hydrogen production capabilities, achieving a maximum cumulative hydrogen yield of 2.22 mol-H2/mol-glucose at 30 °C and pH 7.0, outperforming previously reported E. faecalis strains by 5.84-fold. Kinetic analysis revealed favorable parameters for hydrogen production at 30 °C, with maximum hydrogen production (Hm = 2.63 mol-H2/mol-glucose), maximum hydrogen production rate (Rm = 0.03 mol-H2/mol-glucose·h), and lag-phase time (LPT = 18.34 h). Additionally, E. faecalis isolate VT-H1 exhibited significant butyric acid production (63.0 mM) alongside acetic acid (7.0 mM). Genome analysis unveiled the presence of key enzymes associated with hydrogen production, including formate hydrogen lyase (FHL) complex with formate dehydrogenase subunit alpha (FDH-α), bidirectional [NiFe] hydrogenase, NADH-dependent oxidoreductase subunit E, and NADH-quinone oxidoreductase subunit F. Moreover, genes associated with butyric acid production were also identified. These findings highlight the potential of E. faecalis isolate VT-H1 as a promising candidate for sustainable hydrogen and VFA production. Its unique characteristics, distinct genetic profile, and exceptional hydrogen and VFA production capabilities bring exciting opportunities for future biotechnological applications and further research to optimize and scale-up its potential for industrial use.

Identification and Characterization of a Potential Probiotic, Clostridium butyricum G13, Isolated from the Intestine of the Mud Crab (Scylla paramamosain).

The butyrate-producing bacterium Clostridium butyricum has been proven to be important in improving the growth and health benefits of aquatic animals. In this study, C. butyricum G13 was isolated for the first time from the gut of the mud crab (Scylla paramamosain). The results of this study showed that C. butyricum G13 could produce a high concentration of butyric acid and grow well in a wide range of pHs (4 to 9) and NaCl (1 to 2.5%) and bile salt (0.2 to 1.0%) concentrations. In vitro characterization revealed that C. butyricum G13 is a Gram-positive and gamma-hemolytic bacterium sensitive to most antibiotics and shows hydrophobicity and the capacity to degrade starch. In vitro fermentation using mud crab gut contents showed that C. butyricum G13 alone or in combination with galactooligosaccharides (GOS) and/or resistant starch (RS) significantly increased butyric acid production and beneficially affected the abundance and diversity of intestinal microbiota. In addition, C. butyricum G13 can improve the survival rate of mud crabs and effectively maintain the normal structure of gut morphology after infection with Vibrio parahaemolyticus. In conclusion, C. butyricum G13 can be considered a potential probiotic that improves the immune capacity and confers health benefits on mud crabs. IMPORTANCE With the development of society, more and more aquatic animals are demanded. Intensification in the aquaculture scale is facing problems, such as disease outbreaks, eutrophication of water bodies, and misuse of antibiotics. Among these challenges, disease outbreak is the most important factor directly affecting aquaculture production. It is crucial to explore new approaches effective for the prevention and control of diseases. Probiotics have been widely used in aquaculture and have shown beneficial effects on the host. In this study, the butyrate-producing bacterium Clostridium butyricum G13 was isolated for the first time from the intestine of the mud crab through in vitro fermentation. The bacterium has probiotic properties and changes the gut microbiota to be beneficial to hosts in vitro as well as protecting hosts from Vibrio parahaemolyticus infection in vivo. The outcomes of this study indicate that C. butyricum G13 can be used as a potential probiotic in mud crab aquaculture.

Selective butyric acid production from CO2 and its upgrade to butanol in microbial electrosynthesis cells

Microbial electrosynthesis (MES) is a promising carbon utilization technology, but the low-value products (i.e., acetate or methane) and the high electric power demand hinder its industrial adoption. In this study, electrically efficient MES cells with a low ohmic resistance of 15.7 mΩ m2 were operated galvanostatically in fed-batch mode, alternating periods of high CO2 and H2 availability. This promoted acetic acid and ethanol production, ultimately triggering selective (78% on a carbon basis) butyric acid production via chain elongation. An average production rate of 14.5 g m−2 d−1 was obtained at an applied current of 1.0 or 1.5 mA cm−2, being Megasphaera sp. the key chain elongating player. Inoculating a second cell with the catholyte containing the enriched community resulted in butyric acid production at the same rate as the previous cell, but the lag phase was reduced by 82%. Furthermore, interrupting the CO2 feeding and setting a constant pH2 of 1.7–1.8 atm in the cathode compartment triggered solventogenic butanol production at a pH below 4.8. The efficient cell design resulted in average cell voltages of 2.6–2.8 V and a remarkably low electric energy requirement of 34.6 kWhel kg−1 of butyric acid produced, despite coulombic efficiencies being restricted to 45% due to the cross-over of O2 and H2 through the membrane. In conclusion, this study revealed the optimal operating conditions to achieve energy-efficient butyric acid production from CO2 and suggested a strategy to further upgrade it to valuable butanol.

Effect of zero-valent iron nanoparticles on taxonomic composition and hydrogen production from kitchen waste

This study investigated the effects of varying zero-valent iron (ZVI) (0 to 5,000 mg/L) on fermentative hydrogen (H2) production, metabolic pattern, and taxonomic profile by using kitchen waste as substrate. The study demonstrated that the supplementation of 500 mg ZVI/L resulted in the highest H2 yield (219.68 ± 11.19 mL H2/g-volatile solids (VS)added), which was 19% higher than the control. The metabolic pattern analysis showed that acetic and butyric acid production primarily drove the H2 production. The taxonomic analysis further revealed that Firmicutes (relative abundance (RA): 80–96%) and Clostridium sensu stricto 1 (RA: 68–88%) were the dominant phyla and genera, respectively, during the exponential gas production phase, supporting the observation of accumulation of acetic and butyric acids. These findings suggest that supplementation of ZVI can enhance H2 production from organic waste and significantly influence the metabolic pattern and taxonomic profile, including the metalloenzymes.

Productive, Qualitative, and In Vitro Fermentation Traits of Amaranthus Grains as Potential Ingredients for Pig Diet

The present work compared the agronomic traits, chemical composition, fatty acid profile, and in vitro fermentation characteristics of twelve accessions of Amaranthus spp., belonging to A. cruentus, A. hybridus, A. hypochondriacus, and A. tricolor, grown in a semiarid Mediterranean area. Among accessions, Benin and Arizona (A. cruentus) and Pennsylvania (A. hypochondriacus) showed the highest seed yield (on average, 322.1 g m−2), while Taiwan (A. tricolor) and India and Iowa (A. hypochondriacus) the highest thousand seed weight (on average, 0.81 g). Among the species, A. hypochondriacus showed the highest crude protein (16 g 100g−1), starch (51.5 g 100g−1), and soluble detergent fiber (2.03 g 100g−1) contents and the most favorable in vitro fermentation characteristics with the highest short-chain fatty acid (SCFA 52.6 mmol g−1) and butyric acid (20.7% SCFA) production together with the lowest crude fiber (4.93 g 100g−1) and insoluble dietary fiber (12.5 g 100g−1) content. Arizona (A. cruentus) showed the highest level of monounsaturated fatty acids (32.67 g 100g−1), Ohio (A. hybridus) had the highest levels of polyunsaturated fatty acids (44.62 g 100g−1) and n6-PUFA (44.21 g 100g−1), and India (A. hypochondriacus) had the highest level of n3-PUFA (0.63 g 100g−1). A. hypochondriacus exhibited not only desirable nutritive characteristics, agronomic traits, and suitability to Mediterranean growing conditions, but also a potential beneficial effect. Nonetheless, it is recommended to run longer-term field trials to confirm these findings and to assess the genotype by environment interaction either with current accessions or others from the wide Amaranth germplasm available.

Effects of butyrylated lotus seed starch on small intestinal bacteria and short-chain fatty acid production in mice

With the highest utilization rates of all short-chain fatty acids (SCFAs), butyric acid (BA) is essential for human health. In this study, we investigated butyrylated lotus seed starch (LSB) effects on small intestinal bacteria and SCFA levels in mice. Mouse body weights, after lotus seed resistant starch (RS) and LSB of different degrees of substitution (DS) treatment for 4 weeks, showed no significant difference. LSB of low DS improved small intestine morphology. Relative Lactobacillaceae and Lachnospiraceae abundance was promoted, and several harmful genera e.g., Desulfovibrio were suppressed in LSB groups. From correlation analyses, BA production was negatively related to Bacteroides and Corynebacterium. In this study, we identified butyrylated starch effects on small intestinal bacteria and provided a foundation for designing functional dietary fibers, which induced high BA levels.

Isoalantolactone relieves depression-like behaviors in mice after chronic social defeat stress via the gut-brain axis

RationaleThe management of depression continues to be challenging despite the variety of available antidepressants. Herbal medicines are used in many cultures but lack stringent testing to understand their efficacy and mechanism of action. Isoalantolactone (LAT) from Elecampane (Inula helenium) improved the chronic social defeat stress (CSDS)-induced anhedonia-like phenotype in mice comparable to fluoxetine, a selective serotonin reuptake inhibitor (SSRI).ObjectivesCompare the effects of LAT and fluoxetine on depression-like behaviors in mice exposed to CSDS.ResultThe CSDS-induced decrease in protein expression of postsynaptic density (PSD95), brain derived neurotrophic factor (BDNF), and glutamate receptor subunit-1 (GluA1) in the prefrontal cortex was restored by LAT. LAT showed robust anti-inflammatory activity and can lessen the increase in IL-6 and TNF-α caused by CSDS. CSDS altered the gut microbiota at the taxonomic level, resulting in significant changes in α- and β-diversity. LAT treatment reestablished the bacterial abundance and diversity and increased the production of butyric acid in the gut that was inhibited by CSDS. The levels of butyric acid were negatively correlated with the abundance of Bacteroidetes, and positively correlated with those of Proteobacteria and Firmicutes across all treatment groups.ConclusionsThe current data suggest that, similar to fluoxetine, LAT show antidepressant-like effects in mice exposed to CSDS through the modulation of the gut-brain axis.

Assessment of in vitro digestion of reduced sugar biscuits with extruded brewers’ spent grain

This study aimed to evaluate the nutritional value and potential health claims for reduced sugar biscuits containing extruded brewers’ spent grain (EBSG) and fructooligosaccharides (FOS). One traditional biscuit with added sugar and three reduced sugar biscuits containing 15.2 % FOS and EBSG (0, 8 and 17 %), with nutrition claims “high in fiber” and “source of protein” for those containing 17 % of EBSG, were formulated. Biscuits were characterized by analysis of nutrients and bioactive compounds before and after digestion under in vitro enzymatic oral-gastro-intestinal and colonic fermenting conditions. The bioaccessibility of antioxidants, anti-inflammatory and antidiabetic compounds in biscuits’ intestinal digests and short-chain fatty acids in colonic samples was analyzed. EBSG-added biscuits showed significantly lower (p < 0.05) glucose intestinal bioaccessibility and significantly higher (p < 0.05) phenolic compounds intestinal bioaccessibility compared to biscuits without EBSG. EBSG-added biscuits showed significantly (p < 0.05) higher in vitro antidiabetic potential than the other did. Moreover, the intestinal digest of biscuits containing 17 % EBSG exhibited significantly (p < 0.05) better in vitro inhibition of intracellular ROS formation and in vitro anti-inflammatory properties. FOS addition (p < 0.05) significantly improved the production of butyric acid while EBSG did for valeric acid which possess chemoprotective effect. In conclusion, the combined use of FOS (15.2 %) and EBSG (17 %) allowed obtaining a human healthier snack formulation for satisfying consumers’ demands and achieving nutrition security.

Erchen Decoction alleviates obesity-related hepatic steatosis via modulating gut microbiota-drived butyric acid contents and promoting fatty acid β-oxidation

Ethnopharmacological relevanceErchen decoction (ECD) is a traditional Chinese medicine formula comprising six distinct herbs and has been documented to possess a protective effect against obesity. The study conducted previously demonstrated that ECD has the potential to effectively modulate the composition of gut microbiota and levels of short-chain fatty acids (SCFAs) in obese rat. However, the regulatory mechanism of ECD on gut microbiota and SCFAs and further improvement of obesity have not been thoroughly explained. Aim of the studyThe objective of this study was to examine the therapeutic effect and molecular mechanism of ECD in a rat model of high-fat diet (HFD) feeding. Materials and methodsRats with HFD-induced obesity were treated with ECD. Upon completion of the study, serum and liver samples were procured to conduct biochemical, pathological, and Western blotting analyses. The investigation of alterations in the gut microbiota subsequent to ECD treatment was conducted through the utilization of 16S rRNA sequencing. The metabolic alterations in the cecal contents were examined through the utilization of mass spectrometry-ultraperformance liquid chromatography. ResultsECD treatment improved lipid metabolic disorders and reduced hepatic steatosis in HFD-induced obese rats. Obese rat treated with ECD showed a higher abundance of SCFA-producing bacteria, including Lactobacillus, Bifidobacterium, and Butyricicoccus, and lower abundance of disease-related bacteria, such as Bacteroides, Parabacteroides, and Sediminibacterium. Additionally, ECD caused an increase in total SCFAs levels; in particular, butyric acid was dramatically increased in the HFD group. Rats treated with ECD also exhibited significantly increased butyric acid concentrations in the serum and liver. The subsequent reduction in histone deacetylase 1 expression and increase in acetyl-histone 3-lysine 9 (H3K9ac) levels contributed to the promotion of fatty acid β-oxidation (FAO) in liver by ECD. ConclusionThis study demonstrates that ECD regulates the gut microbiota and promotes butyric acid production to ameliorate obesity-related hepatic steatosis. The mechanism might be related to the promotion of FAO via a butyric acid–mediated increase in H3K9ac levels in the liver.

Effects of Co-Modification by Extrusion and Enzymatic Hydrolysis on Physicochemical Properties of Black Wheat Bran and Its Prebiotic Potential.

Black wheat bran (BWB) is an important source of dietary fiber (DF) and phenolic compounds and has stronger nutritional advantages than ordinary WB. However, the low content of soluble dietary fiber (SDF) negatively influences its physicochemical properties and nutritive functions. To obtain a higher content of SDF in BWB, we evaluated the impact of co-modification by extrusion and enzymes (cellulase, xylanase, high-temperature α-amylase, and acid protease) on water extractable arabinoxylan (WEAX) in BWB. An optimized co-modification method was obtained through single-factor and orthogonal experiments. The prebiotic potential of co-modified BWB was also evaluated using pooled fecal microbiota from young, healthy volunteers. The commonly investigated inulin served as a positive control. After co-modification, WEAX content was dramatically increased from 0.31 g/100 g to 3.03 g/100 g (p < 0.05). The water holding capacity, oil holding capacity, and cholesterol adsorption capacity (pH = 2.0 and pH = 7.0) of BWB were increased by 100%, 71%, 131%, and 133%, respectively (p < 0.05). Scanning electron microscopy demonstrated a looser and more porous microstructure for co-modified BWB granules. Through in vitro anerobic fermentation, co-modified BWB achieved a higher content of Bifidobacterium and Lactobacillus than inulin fermentation. In addition, co-modified BWB induced the highest butyric acid production, indicating high potential as prebiotics. The results may contribute to improving technologies for developing high-fiber-content cereal products.

Simultaneous removal of sulfamethoxazole during fermentative production of short-chain fatty acids

This study explores the simultaneous sulfamethoxazole (SMX) removal and short-chain fatty acids (SCFAs) production by a Clostridium sensu stricto-dominated microbial consortium. SMX is a commonly prescribed and persistent antimicrobial agent frequently detected in aquatic environments, while the prevalence of antibiotic-resistant genes limits the biological removal of SMX. Under strictly anaerobic conditions, sequencing batch cultivation coupled with co-metabolism resulted in the production of butyric acid, valeric acid, succinic acid, and caproic acid. Continuous cultivation in a CSTR achieved a maximum butyric acid production rate and yield of 0.167 g/L/h and 9.56 mg/g COD, respectively, while achieving a maximum SMX degradation rate and removal capacity of 116.06 mg/L/h and 55.8 g SMX/g biomass. Furthermore, continuous anaerobic fermentation reduced sul genes prevalence, thus limiting the transmission of antibiotic resistance genes during antibiotic degradation. These findings suggest a promising approach for efficient antibiotic elimination while simultaneously producing valuable products (e.g., SCFAs).

Probiotic potential of Lactiplantibacillus plantarum ZFM4 isolated from pickles and its effects on human intestinal microecology

Lactic acid bacteria have received worldwide attention because of their fermentative properties and their great significance for the balance of microbial homeostasis in the intestine. In this study, we isolated a strain of Lactiplantibacillus plantarum ZFM4 from pickles and evaluated its probiotic properties. The results indicated that ZFM4 was suppressive to most pathogenic bacteria, especially Staphylococcus aureus and Pseudomonas aeruginosa, and showed good tolerance to high osmotic pressure (8.0% NaCl), high ethanol concentration (5.0%), high temperature (42 °C) and bile salts (0.3%, 4 h). The effect of ZFM4 on human intestinal microbiota was investigated through the fecal slurry fermentation model in vitro. Sequencing of the 16S rDNA gene demonstrated that the addition of ZFM4 significantly raised the abundance of phylum Bacillota, while increased the proportion of beneficial genera, such as Lactiplantibacillus and Bifidobacterium. Furthermore, ZFM4 contributed to the enhanced production of acetic acid, butyric acid, valeric acid, and isovaleric acid. In summary, ZFM4 could be considered a potential probiotic candidate.

Gut Microbiota Mediates Lactobacillus rhamnosus GG Alleviation of Deoxynivalenol-Induced Anorexia.

Deoxynivalenol (DON) is a widespread mycotoxin and causes anorexia and emesis in humans and animals; Lactobacillus rhamnosus GG (LGG), a well-characterized probiotic, can improve intestinal barrier function and modulate immune response. Currently, it is unclear whether LGG has a beneficial effect on DON-induced anorexia. In the present study, mice were treated with DON, LGG, or both by gavage for 28 days to evaluate the effects of LGG on DON-induced anorexia. Antibiotic treatment and fecal microbiota transplant (FMT) experiment were also conducted to investigate the link between DON, LGG, and gut microbiota. LGG significantly increased the villus height and reduced the crypt depth in jejunum and ileum, enhanced the tight junction proteins expression in the intestine, and regulated the TLR4/NF-κB signaling pathway, consequently attenuating the intestinal inflammation caused by DON. In addition, LGG increased the relative abundance of Lactobacillus and butyric acid production of cecal contents; remodeled phenylalanine metabolism and tryptophan metabolism; reduced plasma peptide tyrosine tyrosine (PYY), 5-hydroxytryptamine (5-HT), and glucagon-like peptide-1 (GLP-1) concentrations; and promoted hypothalamic NPY and AgPR gene expression, which will further promote food intake and reduce weight loss, ultimately alleviating DON-induced anorexia in mice. Interestingly, antibiotic treatment diminished the intestinal toxicity of DON. The FMT experiment showed that DON-originated microbiota promotes intestinal inflammation and anorexia, while LGG + DON-originated microbiota has no adverse effects on mice. Both antibiotic treatment and FMT experiment have proved that gut microbiota was the primary vector for DON to exert its toxic effects and an essential mediator of LGG protection. In summary, our findings demonstrate that gut microbiota plays essential roles in DON-induced anorexia, and LGG can reduce the adverse effects caused by DON through its structure and regulate the gut microbiota, which may lay the important scientific foundation for future applications of LGG in food and feed products.

In Vitro Fermentation of Different Indigestible Glucans with Varying Physico-Chemical Properties by Human Fecal Microbiota

Indigestible glucans (IGs) are dietary fibers that can promote human health via fermentation by the gut microbiota, where their physico-chemical properties play a crucial role. This effect remains to be fully explored. The aim of the current study was to comprehensively investigate and compare the fermentation characteristics of IGs with various structural properties, as well as their effects on the gut microbiota. Barley β-glucan (BG), laminarin (L), yeast β-glucan (BY), pachyman (PAC), resistant starch (R), and litesse (Lit) were anaerobically batch-fermented using the human fecal microbiota for 48 h. All the IGs were utilized by the gut microbiota at different rates, and 2% of L, 14% of BG, 23% of BY and PAC, and 35% of R and Lit were unfermented at the 48th hour. During fermentation, mono-, di-, or trisaccharides were released from BG, L, and Lit, and the pH of broth was greatly lowered by IGs, especially BG and L, along with the production of short-chain fatty acids. Interestingly, PAC favored butyric acid production, while BG, L, and BY preferred propionic acid. Moreover, lactic acid, but not succinic acid, was detected in considerable amounts, but only with BG and L after 5 h. 16S rDNA analysis showed different microbial structures and the selective promotion of bacteria with different IGs, while only PAC did not decrease microbial α-diversity. Further qPCR analysis confirmed that BG was more potent at proliferating Faecalibacterium prausnitzii; BY preferred total bacteria, Prevotella, and Lactobacillus; and R favored Bifidobacterium. The IG-induced changes in the gut microbiota were strongly correlated with carboxylic acid production. In conclusion, the six IGs differed in fermentation characteristics and gut microbiota regulation capacity, and each one could have specific applications in human health promotion.