Vibrio parahaemolyticus is a primary seafood-associated pathogen that could cause gastroenteritis. It can attach to various surfaces and form a biofilm, which poses serious threats to food safety. Hence, an effective strategy is urgently needed to control the biofilm formation of V. parahaemolyticus. Laurel essential oil (LEO) is used in food, pharmaceutical and other industries, and is commonly used as a flavoring agent and valuable spice in food industries. The potential antibiofilm effects of LEO against V. parahaemolyticus were examined in this study. LEO obviously reduced biofilm biomass at subinhibitory concentrations (SICs). It decreased the metabolic activity and viability of biofilm cells. Microscopic images and Raman spectrum indicted that LEO interfered with the structure and biochemical compositions of biofilms. Moreover, it also impaired swimming motility, decreased hydrophobicity, inhibited auto-aggregation and reduced attachment to different food-contact surfaces. RT-qPCR revealed that LEO significantly downregulated transcription levels of biofilm-associated genes of V. parahaemolyticus. These findings demonstrate that LEO could be potentially developed as an antibiofilm strategy to control V. parahaemolyticus biofilms in food industries.

Probiotics have garnered escalating attention in the treatment and prevention of inflammatory disorders. In this study, Lactobacillus rhamnosus RL-H3-005 (RL5) and Pediococcus acidilactici RP-H3-006 (RP6), which possess anti-inflammatory effects and favorable probiotic attributes, were selected through the comparison of an RAW264.7 inflammatory cell model screening and in vitro probiotic properties. Subsequently, it was implemented in an animal model of dextran sulfate sodium (DSS)-induced colitis. The results demonstrated that RL5 and RP6 could inhibit the release of proinflammatory factors in RAW264.7 inflammatory cells and exhibited excellent environmental adaptability, adhesion, safety, and antibacterial activity. Additionally, RL5 and RP6 provided protective effects on the intestines of mice with acute colitis by reducing the levels of intestinal inflammation and oxidative stress. Concurrently, supplementation with RL5 and RP6 modulated the composition of the gut microbiota in mice. These discoveries suggest that RL5 and RP6 can be used as a novel probiotic for alleviating intestinal inflammation.

Plant polysaccharide intervention has shown significant potential to combat obesity. However, studies on animal polysaccharides are indeed rare. The aim of this study was to investigate the potential functions of CIP (IL) on obesity, intestinal microflora dysbiosis, and the possible protection of intestinal barrier in mice fed with high-fat diet (HFD). Our results revealed that after 13 weeks, the HFD+L (high-fat diet + 25 mg/kg CIP) group showed significantly more weight loss and fat accumulation relative to the HFD+H (high-fat diet + 50 mg/kg CIP) group. Furthermore, CIP intervention modulated lipid metabolism and mRNA levels of inflammatory mediators in liver. Overall, CIP clearly improved the intestinal barrier in HFD-fed mice. Additionally, we observed that CIP intervention improved intestinal microbiota community richness and diversity in HFD-fed mice. The CIP intervention mice group showed a relatively low Firmicutes to Bacteroidetes ratio compared to the HFD group. This study concluded that CIP could be used as a functional food to prevent adipocyte accumulation, reduce systemic inflammation, and protect the intestinal barrier.

Atopic Dermatitis (AD) is a common inflammatory skin disease characterized primarily by its chronic and recurrent nature. This has a significant impact on productivity and human longevity. Dysbiosis of gut flora has been demonstrated to be significantly associated with the progression of AD. In our previous research, it was shown that Lactobacillus rhamnosus RL5-H3-005 (RL) and Pediococcus acidilactici RP-H3-006 (RP) have the ability to reduce the risk of disease in AD mice through the gut–mammary axis. Based on our previous work, this study aims to further investigate the effects of kynurenine (KYN), a metabolite of RL and RP, on AD mice induced by 2, 4-dinitrofluorobenzene (DNFB). In this study, we found that supplementing KYN in AD mice effectively alleviates the pathological symptoms of atopic dermatitis and further improves the levels of SCFAs in their intestines. Further research indicates that KYN’s therapeutic effects on AD are primarily manifested in the reduction of secretory immunoglobulin A (sIgA), immunoglobulin E (IgE), interleukin-4 (IL-4), IL-5, IL-13, and thymic stromal lymphopoietin (TSLP) levels in mice, while also repairing the intestinal barrier function of AD mice. Overall, the metabolites KYN of probiotics RL and RP can regulate the levels of SCFAs of mice, potentially improving the symptoms of AD mice through the gut–skin axis.