Co-culture of Bacillus coagulans and Candida utilis efficiently treats Lactobacillus fermentation wastewater

Impact of Bacillus licheniformis from yaks following antibiotic therapy in mouse model

Gut microorganism (GM) is an integral component of the host microbiome and health system. Abuse of antibiotics disrupts the equilibrium of the microbiome, affecting environmental pathogens and host-associated bacteria alike. However, relatively little research on Bacillus licheniformis alleviates the adverse effects of antibiotics. To test the effect of B. licheniformis as a probiotic supplement against the effects of antibiotics, cefalexin was applied, and the recovery from cefalexin-induced jejunal community disorder and intestinal barrier damage was investigated by pathology, real-time PCR (RT-PCR), and high-throughput sequencing (HTS). The result showed that A group (antibiotic treatment) significantly reduced body weight and decreased the length of jejunal intestinal villi and the villi to crypt (V/C) value, which also caused structural damage to the jejunal mucosa. Meanwhile, antibiotic treatment suppressed the mRNA expression of tight junction proteins ZO-1, claudin, occludin, and Ki67 and elevated MUC2 expression more than the other Groups (P < 0.05 and P < 0.01). However, T group (B. licheniformis supplements after antibiotic treatment) restored the expression of the above genes, and there was no statistically significant difference compared to the control group (P > 0.05). Moreover, the antibiotic treatment increased the relative abundance of 4 bacterial phyla affiliated with 16 bacterial genera in the jejunum community, including the dominant Firmicutes, Proteobacteria, and Cyanobacteria in the jejunum. B. licheniformis supplements after antibiotic treatment reduced the relative abundance of Bacteroidetes and Proteobacteria and increased the relative abundance of Firmicutes, Epsilonbacteraeota, Lactobacillus, and Candidatus Stoquefichus. This study uses mimic real-world exposure scenarios by considering the concentration and duration of exposure relevant to environmental antibiotic contamination levels. We described the post-antibiotic treatment with B. licheniformis could restore intestinal microbiome disorders and repair the intestinal barrier. KEY POINTS: • B. licheniformis post-antibiotics restore gut balance, repair barrier, and aid health • Antibiotics harm the gut barrier, alter structure, and raise disease risk • Long-term antibiotics affect the gut and increase disease susceptibility.

Multi-dimensional experimental and computational exploration of metabolism pinpoints complex probiotic interactions

Multi-strain probiotics are widely regarded as effective products for improving gut microbiota stability and host health, providing advantages over single-strain probiotics. However, in general, it is unclear to what extent different strains would cooperate or compete for resources, and how the establishment of a common biofilm microenvironment could influence their interactions. In this work, we develop an integrative experimental and computational approach to comprehensively assess the metabolic functionality and interactions of probiotics across growth conditions. Our approach combines co-culture assays with genome-scale modelling of metabolism and multivariate data analysis, thus exploiting complementary data- and knowledge-driven systems biology techniques. To show the advantages of the proposed approach, we apply it to the study of the interactions between two widely used probiotic strains of Lactobacillus reuteri and Saccharomyces boulardii, characterising their production potential for compounds that can be beneficial to human health. Our results show that these strains can establish a mixed cooperative-antagonistic interaction best explained by competition for shared resources, with an increased individual exchange but an often decreased net production of amino acids and short-chain fatty acids. Overall, our work provides a strategy that can be used to explore microbial metabolic fingerprints of biotechnological interest, capable of capturing multifaceted equilibria even in simple microbial consortia.