Ulcerative colitis (UC), one of the typical inflammatory bowel diseases caused by dysregulated immunity, still requires novel therapeutic medicine with high efficacy and low toxicity. Hericium erinaceus has been widely used to treat different health problems especially gastrointestinal sickness in China for thousands of years. Here, we isolated, purified, and characterized a novel low weight polysaccharide (HEP10, Mw: 9.9 kDa) from the mycelia of H. erinaceus in submerged culture. We explored the therapeutic effect of HEP10 on UC and explored its underlying mechanisms. On one hand, HEP10 suppressed the production of TNF-α, IL-1β, IL-6, inducible iNOS, and COX-2 in LPS challenged murine macrophage RAW264.7 cells, as well as in colons from DSS-induced colitis mice. On the other hand, HEP10 treatment markedly suppressed the activation of NLRP3 inflammasome, NF-κB, AKT, and MAPK pathways. Moreover, HEP10 reversed DSS-induced alternation of the gut community composition and structure by significantly increasing Akkermansia muciniphila and also promoting functional shifts in gut microbiota. Structural equation modeling also highlighted that HEP10 can change widely through gut microbiota. In conclusion, HEP10 has a better prebiotic effect than the crude polysaccharides of H. erinaceus, which can be used as a novel dietary supplement and prebiotic to ameliorate colitis.

Antrodia cinnamomea is a precious and popular edible and medicinal mushroom. It has attracted increasing attention due to its various and excellent bioactivities, such as hepatoprotection, hypoglycemic, antioxidant, antitumor, anticancer, anti-inflammatory, immunomodulation, and gut microbiota regulation properties. To elucidate its bioactivities and develop novel functional foods or medicines, numerous studies have focused on the isolation and identification of the bioactive compounds of A. cinnamomea. In this review, the recent advances in bioactivity, isolation, purification, and identification methods of active compounds from A. cinnamomea were summarized. The present work is beneficial to the further isolation and discovery of new active compounds from A. cinnamomea.

Biofilm formation is usually affected by many environmental factors, including divalent cations. The purpose of the current work was to analyze how calcium (Ca²⁺) affects the biofilm formation of dairy Pseudomonas fluorescens isolates by investigating their growth, swarming motility, biofilm-forming capacity, extracellular polymeric substance production, and biofilm structures. Moreover, the regulation mechanism of Ca²⁺ involved in its biofilm formation was explored through RNA-sequencing analysis. This work revealed that supplementation of 5, 10, 15, and 20 mM Ca²⁺ significantly reduced the swarming motility of P. fluorescens strains (P.F₂, P.F₄, and P.F₁₇), but the biofilm-forming ability and polysaccharide production were increased after the supplementation of 5 and 10 mM Ca²⁺. By the supplementation of Ca²⁺, complex structures with more cell clusters glued together in P. fluorescens P.F₄ biofilms were confirmed by scanning electron microscopy, and increased biomass and coverage of P. fluorescens P.F₄ biofilms were observed by confocal laser scanning microscopy. In addition, RNA-sequencing results showed that P. fluorescens P.F₄ showed a transcriptional response to the supplementation of 10 mM Ca²⁺, and a total of 137 genes were significantly expressed. The differential genes were represented in 4 upregulated Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways (nonribosomal peptide structures, quorum sensing, biosynthesis of siderophore group nonribosomal peptides, and phenylalanine metabolism), and 4 downregulated KEGG pathways (flagellar assembly, amino sugar and nucleotide sugar metabolism, nitrotoluene degradation, and cationic antimicrobial peptide resistance). The results indicate that Ca²⁺ might serve as an enhancer to substantially trigger the biofilm formation of dairy P. fluorescens isolates in the dairy industry.

Antrodia (A) cinnamomea is a precious edible and medicinal mushroom and has attracted attention because of its rare resources and unique bioactivities. The bioactive compounds from the fruit body, mycelium, and fermentation broth of A. cinnamomea include triterpenoids, polysaccharides, antroquinonols, benzenoids, and succinic and maleic acid derivatives. Among these, polysaccharides are very important and are high-content bioactive compounds. The A. cinnamomea polysaccharides (APSs) present numerous biological activities, such as antiviral, anticancer, anti-inflammatory, antivascular, immunoregulation, antioxidant, and nerve protection. However, only few studies have focused only on APSs so far. Therefore, the cultivation methods, extraction, isolation, composition, structure, biological activity, and application of APSs are summarized in this review to provide a comprehensive and convenient reference for further research and development on APSs.