ABSTRACT
Objective: To study the biotransformation of gracillin by Penicillium lilacinumACC 31890,to isolate and to identify the structures of metabolites and investigate the pharmacological activities.Methods: The conversion products were isolated and purified by silica gel column chromatography and semi-preparative reversed phase liquid chromatography.Their structures were identified by MS and NMR, and the anti-inflammatory activity of the conversion products was investigated as well.Results: Three metabolites were isolated and purified, and identified as 5R-spirost-5-ene-3-ol-O-β-D-Glucopyranoside-(1→3)-β-D-glucopyranosyl (1), trillin (2) and diosgenin (3) with the conversion rate of 1%, 1% and 45%, respectively.In vitro study showed that the three products showed certain degrees of activity to inhibit the production of NO, IL-6 and MCP-1 in LPS-primed RAW264.7 macrophages.Moreover, the anti-inflammatory activity of the bioconversion products increased along with the hydrolyzation of carbohydrate chain.Diosgenin, the final product, showed the strongest anti-inflammatory activity among the three products.Conclusion: The biotransformation of gracillin by Penicillium lilacinum has a high productivity of diosgenin.The amount of glycosyls has notable influence on the anti-inflammatory activity of steroid sapoinin.