Antimicrobial resistance was one of serious worldwide problems confused many researchers. To solve this problem, we explored the antibacterial effect of chelerythrine, a natural compound from traditional Chinese medicine and studied its action. The contents of chelerythrine from different fractions of Toddalia asiatica (Linn) Lam (T. asiatica) were determined. The anti-bacterial activities of chelerythrine were tested by disc diffusion method (K-B method). Scanning electron microscopy (SEM), alkaline phosphatase (AKP), bacterial extracellular protein leakage and SDS-PAGE analysis were also used to investigate the antibacterial mechanism of chelerythrine. Analytic results of High Performance Liquid Chromatography showed that the content of chelerythrine (1.97 mg/g) in the ethyl acetate fraction was the highest, followed by those of methanol fraction and petroleum ether fraction. The in vitro anti-bacterial mechanisms of chelerythrine from T. asiatica were assessed. Chelerythrine showed strong antibacterial activities against Gram-positive bacteria, Staphylococcus aureus (SA), Methicillin-resistant S. aureus (MRSA), and extended spectrum β-lactamase S. aureus (ESBLs-SA). The minimum inhibitory concentrations (MICs) of chelerythrine on three bacteria were all 0.156 mg/mL. Furthermore, results suggested that the primary anti-bacterial mechanism of chelerythrine may be attributed to its destruction of the channels across the bacterial cell membranes, causing protein leakage to the outside of the cell, and to its inhibition on protein biosynthesis. Images of scanning electron microscope revealed severe morphological changes in chelerythrine-treated bacteria except control, damage of parts of the cell wall and cell membrane as well as the leakage of some substances. Chelerythrine isolated from root of Toddalia asiatica (Linn) Lam possesses antibacterial activities through destruction of bacterial cell wall and cell membrance and inhibition of protein biosynthesis.

Hyperlipidemia is a kind of lipid metabolism disease, whose pathogenesis is complex and diverse, mainly related to abnormal glucose and lipid metabolism, as well as insulin resistance and other characteristics. Because of their low toxic and side effects along with clear medicinal effects, the food and medicinal homological resources are widely used in the regulation of blood lipids in recent years. The State Administration for Market Regulation website and various databases have been searched for the use of food and medicinal homological materials in functional food products, the categories and frequency in food and medicinal homological resources, the lipid-lowering active ingredients and their mechanisms. The results showed that 53 kinds of food and medicinal homological resources were used to regulate blood lipids, of which Crataegus pinnatifida Bge., Cassia obtusifolia L., Nelumbo nucifera Gaertn., Morus alba L. and Pueraria lobata (Willd.) Ohwi were used most frequently. The main active ingredients are triterpenes and their glycosides, flavonoids, alkaloids and polysaccharides, etc., they regulated blood lipid levels and cholesterol metabolism by activating AMPK and PPARγ.

Proteomics and intestinal flora were used to determine the mechanism of immune modulatory effects of Flammulina velutipes polysaccharide on immunosuppressed mice. The results showed that compared with the model group, F. velutipes polysaccharide could increase thymus and spleen indices and improve thymus tissue structure in mice; IL-2 and IL-4 contents were significantly increased and IL-6 and TNF-α contents were significantly decreased; serum acid phosphatase (ACP), lactate dehydrogenase (LDH) and total antioxidant capacity (T-AOC) activities were increased (P < 0.05); in the liver, superoxide dismutase (SOD) and catalase (CAT) activities were increased (P < 0.001), while malondialdehyde (MDA) content was decreased (P < 0.001). Proteomics discovered that F. velutipes polysaccharides may exert immune modulatory effects by participating in signaling pathways such as immune diseases, transport and catabolism, phagosomes and influenza A, regulating the immune-related proteins Transferrin receptor protein 1 (TFRC) and Radical S-adenosyl methionine domain-containing protein 2 (RSAD2), etc. Gut microbial studies showed that F. velutipes polysaccharides could increase the abundance of intestinal flora and improve the flora structure. Compared to the model group, the content of short-chain fatty acids (SCFAs) and the relative abundance of SCFA-producers Bacteroides and Alloprevotella were increased in the F. velutipes polysaccharide administration group, while Lachnospiraceae_NK4A136_group and f_Lachnospiraceae_Unclassified decreased in relative abundance. Thus, F. velutipes polysaccharide may play an immunomodulatory role by regulating the intestinal environment and improving the balance of flora.