Yunxiang Liang

High‐density solid‐state fermented probiotic products, combining live bacteria with microbial and substrate‐derived bioactives, offer a potential solution to address dysregulation of gut microbiota–immune homeostasis associated with inflammatory bowel disease (IBD). However, their synergistic efficacy against IBD remains elusive. Here, we discuss our high‐density solid‐state fermented Lacticaseibacillus paracasei culture (PYW) and its effects on dextran sulfate sodium (DSS)‐induced colitis. Comparison of the effects of PYW, enriched with viable cells and bioactive metabolites—obtained via fermentation with wheat bran—with those of its thermally inactivated postbiotic (SPYW) shows superior efficacy of PYW than SPYW, with a viable bacterial load of ≥ 5 × 10 ¹⁰ CFU g ⁻¹ being indispensable. PYW effectively restores microbiota structure, restructures the gut tryptophan metabolic network, enriching indole‐3‐lactic acid (ILA) and indole‐3‐acetic acid (IAA), which activate the aryl hydrocarbon receptor (AhR) signaling pathway, suppress pro‐inflammatory mediators, and strengthen mucosal barriers. Antibiotic depletion abolishes the effects of PYW, while fecal microbiota transplantation from PYW‐treated donors and exogenous ILA/IAA supplementation replicate its anti‐colitic benefits. These findings suggest that PYW alleviates colitis via microbiota‐dependent enrichment of ILA/IAA and subsequent AhR pathway activation, highlighting its potential as a probiotic therapeutic targeting the microbiota–metabolism–immunity regulatory axis in IBD.

Soybean meal causes health issues in piglets due to the presence of antigenic proteins. Although enzymatic treatment can break down antigenic proteins, subsequent high-temperature drying may impair amino acid (AA) digestibility via the Maillard reaction. This study evaluated whether the air-drying temperature affects the ileal AA digestibility of a novel reduced-sugar enzyme-treated soybean meal (ESM) in 25 kg pigs, using fishmeal as a high-digestibility reference. In two trials using pigs fitted with simple T-cannulas in the terminal ileum, ileal digestibility was assessed. In trial 1, a replicated 3 × 3 Latin square design with three diets (fishmeal, ESM, and a nitrogen-free diet; two pigs per diet) and three periods were used per square. Fishmeal showed greater apparent (82.50% vs. 45.01%) and standardized (86.60% vs. 48.86%) digestibility of crude protein and all amino acids than ESM dried at 130 °C. In trial 2, eight pigs were allocated to two diets in a two-period crossover design to compare the AA digestibility of ESM dried at high (130 °C; HtESM) and low (80 °C; LtESM) temperatures. LtESM exhibited greater apparent (82.24% vs. 52.40%) and standardized (86.37% vs. 56.47%) digestibility of crude protein and more amino acids than HtESM. Collectively, the drying temperature critically determined the AA digestibility of ESM, irrespective of its reducing sugar content.

This study investigates the efficacy of fermented corn straw as a viable corn substitute in rabbit diets, evaluating its impact on growth performance, intestinal health, cecal microbiota, and metabolite profiles to determine its potential for addressing corn shortages in animal husbandry. Over 35 days, 120 New Zealand rabbits were assigned to four treatments: (i) 12% corn (C100), (ii) 6% corn + 6% fermented straw (FS50), (iii) 12% fermented straw (FS100), and (iv) 6% corn + 6% dry straw (DS50). Fermented straw enhanced the rabbits’ average daily feed intake (ADI) and average daily gain (ADG) and elevated cecal cellulase activity. It also downregulated TLR4 in the jejunum mucosa, upregulated MUC2 in the ileum mucosa, strengthened the intestinal barrier, and reduced the diarrhea index and incidence in weaned rabbits. Specific microbial families influenced amino acid and phospholipid concentrations, altering the cecal metabolic environment. In summary, replacing corn with fermented corn straw in rabbit diets significantly boosts ADG and ADI, potentially lowers the feed-to-gain ratio, and enhances cecal microbiota and metabolite profiles without compromising growth performance.

Corn, as a raw material supplying energy, plays an important role in animal husbandry. But in recent years, problems related to insufficient energy supply from corn have attracted increasing attention. Therefore, it is highly important to develop new energy-supplying materials to replace corn in animal diets. To study the feasibility of replacing corn with fermented corn straw in ruminants, 16 Yichang white goats were divided into two groups: those kept on a grain-based diet with dry corn straw (DS) and those fed a grain-based diet with fermented corn straw (FS). Corn in the FS group was replaced with fermented corn straw at a ratio of 1.3:1. By increasing the surface area (p = 0.035) and width (p = 0.024) of the rumen epithelial papillae of Yichang white goats, the absolute enzyme activity of carboxymethyl cellulase and the relative enzyme activity of microcrystalline cellulase in the rumen contents increased with fermented corn straw, and the rumen digestibility of cellulose and the whole intestinal apparent digestibility of CP, CF, NDF, ADF, cellulose and hemicellulose increased. The timely removal of excess calcium through feces and urine prevented liver and kidney damage, improved the heart index and liver index, and sustained goat health. Due to an increase in the abundance of beneficial bacteria such as f-Lachnospiraceae and c_Bacilli in the rumen fluid and colon contents, the abundance of potentially harmful bacteria such as s_Turicibacter decreased. Through the rumen pentose phosphate pathway, carbon metabolism, the AMPK signaling pathway, pathways of neurodegeneration, multiple diseases pathways, vitamin b6 metabolism in the colon, the biosynthesis of nucleotide sugars, and the cysteine and methionine metabolism pathways, rumen fermentation and metabolism are regulated in the goat body, promoting animal health. In this study, we systematically evaluated the effects of replacing corn with fermented corn straw on the carcass index, organ index, calcium and phosphorus contents in tissues, serum biochemical parameters, nutrient digestibility, rumen epithelium and intestinal development, rumen fermentation, and microbial enzyme activity of the rumen contents of Yichang white goats. By combining these approaches with microbial 16S amplicon analysis of rumen fluid and colon contents, along with nontargeted metabolome analysis, we demonstrated the feasibility of substituting corn with fermented corn straw in ruminant feed, providing a new approach for the substitution of energy-supplying feed materials.

The aim of the present study was to investigate the dietary effects of replacing corn with different proportions of fermented straw on the growth performance and intestinal health of finishing pigs. A total of 275 healthy commercial finishing pigs aged 126 days (average body weight, 82.96 ± 3.07 kg) were randomly allocated into three groups: the control (CTR, basal diet) group, the 5% fermented straw (FJJG5, replacing 5% of the corn) group, and the 10% fermented straw (FJJG10, replacing 10% of the corn) group. There were six replicates in each group and 14–16 pigs per replicate. On day 39 of the experiment, one animal from each replicate was slaughtered for sampling and for further analysis. The results showed that the finishing pigs in the FJJG10 group had a reduced average daily weight gain and an increased feed-to-gain ratio. The FJJG5 group had reduced total cholesterol, high-density lipoprotein, and low-density lipoprotein in their serum, while the FJJG5 and FJJG10 groups had reduced contents of lactate dehydrogenase. In addition, the FJJG5 group exhibited increased T-SOD activity and MDA content in the colon, while the FJJG10 group also showed increased T-AOC activity in their serum and increased contents of MDA in the colon. The FJJG5 group exhibited increased activities of jejunal disaccharidase and lipase, while the FJJG10 group exhibited decreased jejunal crypt depths. Moreover, the FJJG5 group presented an increased relative expression of APOA4, LPL, and MUC2 but decreased SLC7A7 and IL-10 in the jejunum and APOA4 in the colon. The FJJG10 group exhibited a decreased relative expression of SLC7A7 and IL-10 in the jejunum and decreased MMP13, KCNJ13, APOA4, SLC7A7, LPL, and IL-10 in the colon. Furthermore, the FJJG5 group exhibited an increased relative abundance of Lactobacillus in colon contents, while the FJJG10 group had a reduced relative abundance of streptococcus. In conclusion, 5% fermented straw can improve the lipid metabolism and colon microbiota structure of finishing pigs, while 10% fermented straw has adverse effects on the growth performance and intestinal health of finishing pigs.

Probiotics and their postbiotics have the potential to improve the health and growth performance of piglets, which has brought them widespread attention in the post-antibiotic era. In the present study, the effects of dietary supplementation of Lactobacillus reuteri postbiotics on the growth performance, intestinal flora structure and plasma metabolome of weaned piglets were investigated. A total of 816 healthy male piglets with uniform weight were divided into two treatment groups: piglets in the control (CTR) group were fed with a basic diet, and the ones in the LAC group were fed with the basic diet supplemented with 500 mg/kg Lactobacillus reuteri postbiotics. There were six replicates in each group and 68 piglets in each replicate. The animal trial lasted for 30 days. The feces and blood of piglets were collected for investigation, and the growth performance during the trial was counted. Our outcomes show that dietary supplementation with Lactobacillus reuteri postbiotics had no effect on the growth performance of piglets; however, it reduced the mortality rate of piglets by 6.37%. The levels of total superoxide dismutase in the serum, propionic acid and butyric acid in the feces were elevated, and the content of malondialdehyde in the serum was decreased with Lactobacillus reuteri postbiotics-treated piglets (p < 0.05). The fecal flora sequencing results show that the relative abundance of Firmicutes and monoglobus was upregulated, and the relative abundance of Bacteroides was downregulated with Lactobacillus reuteri postbiotics-treated piglets (p < 0.05). In addition, the levels of propionic acid and butyric acid in the feces were positively correlated with the relative abundance of Firmicutes and negatively correlated with the relative abundance of Bacteroides (p < 0.05). The plasma metabolome results show that dietary supplementation with Lactobacillus reuteri postbiotics raised the level of coenzyme Q10 in the serum, and the abundance of coenzyme Q10 was positively correlated with the relative abundance of Firmicutes and the level of total superoxide dismutase in the serum. In conclusion, dietary supplementation with Lactobacillus reuteri postbiotics contributed to improving the antioxidant function and reducing the mortality of piglets by regulating the structure of intestinal flora and upregulating the content of coenzyme Q10 in serum.

Returning corn straw to the field is beneficial for improving soil fertility, but the fermentation phase significantly affects the dissolved organic carbon (DOC) content. However, there is limited research on the effects of straw at different fermentation phases on soil microorganisms and soil nutrients. This study examined the effects of high-temperature fermentation phase straw (HF) and completely fermentation phase straw (CF) on soil nutrient activation and microorganism activity through pot experiments. The pot experiment results indicated a significant increase in soil DOC content following the application of corn straw, among which the high-temperature fermentation phase straw treatment (T_HF) exhibited the highest DOC content, which was 14% higher than the completely fermentation phase straw treatment (T_CF). T_HF also significantly increased soil alkaline hydrolyzed nitrogen and available phosphorus content as well as urease and phosphatase, and promoted the uptake of nitrogen and phosphorus from soil by Brassica chinensis. T_HF significantly enhanced bacterial diversity and reduced the presence of pathogenic fungi. Compared to the TCF, the relative proportion of Fusarium under the T_HF decreased by 32.24%, effectively mitigating the impact of pathogenic fungi. T_HF also increased soil DOC content, enriched beneficial microbial community structure, increased soil enzyme activity, activated soil nutrients, thereby promoting the uptake of nitrogen and phosphorus by crops. Taken together, the results reveal that the application of high-temperature fermentation phase straw is conducive to soil fertilization and crop growth.

This study investigated the effects of solid-state fermentation with Clostridium butyricum on the microstructure of wheat bran, the release of dietary fiber and phenolic compounds, and antioxidant capacity. Compared with unfermented wheat bran, insoluble dietary fiber and phytic acid content decreased, whereas soluble dietary fiber and water-extractable arabinoxylan content increased in C. butyricum culture. Because of the increased release of phenolic compounds, such as ferulic acid and apigenin, and organic acids, such as isobutyric acid, the antioxidant capacity of the culture was considerably improved. Furthermore, the culture of C. butyricum treated with dextran sulfate sodium-induced ulcerative colitis in mice enhanced the expression of intestinal mucus and tight-junction proteins, modulating the gut microbiota structure, increasing the levels of short-chain fatty acids in the intestine, and restoring the essential functions of the gut microbiota. These anti-inflammatory effects stemmed from the combined action of various effective components.

Chlorella vulgaris is one of the most commonly used microalgae in aquaculture feeds. It contains high concentrations of various kinds of nutritional elements that are involved in the physiological regulation of aquaculture animals. However, few studies have been conducted to illustrate their influence on the gut microbiota in fish. In this work, the gut microbiota of Nile tilapia (Oreochromis niloticus) (average weight is 6.64 g) was analyzed by high-throughput sequencing of the 16S rRNA gene after feeding with 0.5% and 2% C. vulgaris additives in diets for 15 and 30 days (average water temperature was 26 °C). We found that the impact of C. vulgaris on the gut microbiota of Nile tilapia was feeding-time dependent. Only by feeding for 30 days (not 15 days) did the addition of 2% C. vulgaris to diets significantly elevate the alpha diversity (Chao1, Faith pd, Shannon, Simpson, and the number of observed species) of the gut microbiota. Similarly, C. vulgaris exerted a significant effect on the beta diversity (Bray–Curtis similarity) of the gut microbiota after feeding for 30 days (not 15 days). During the 15-day feeding trial, LEfSe analysis showed that Paracoccus, Thiobacillus, Dechloromonas, and Desulfococcus were enriched under 2% C. vulgaris treatment. During the 30-day feeding trial, Afipia, Ochrobactrum, Polymorphum, Albidovulum, Pseudacidovorax, and Thiolamprovum were more abundant in 2% C. vulgaris-treated fish. C. vulgaris promoted the interaction of gut microbiota in juvenile Nile tilapia by increasing the abundance of Reyranella. Moreover, during the feeding time of 15 days, the gut microbes interacted more closely than those during the feeding time of 30 days. This work will be valuable for understanding how C. vulgaris in diets impacts the gut microbiota in fish.