Herba Epimedii's biotransformation in vitro simulated gastrointestinal digestion and faecal fermentation systems / 中国药理学与毒理学杂志

ABSTRACT

OBJECTIVE Epimedium is rich in a variety of beneficial active ingredients, and has been widely used in the ethnopharmacological practices, however, its biotransformation in gastrointestinal digestions remain unclear. This study aimed to investigate the dynamic changes of components and biological activity of Epimedium in the in vitro simu? lated digestion and subsequent human faecal fermentation. METHODS The models of in vitro simulated saliva, gastric and intestinal digestion, as well as colonic fermentation were constructed to simulate the digestion process of Epimedium. The dynamic changes of components of Epimedium during the simulated digestions in vitro and subsequent human faecal fermentation were investigated by UPLC-MS, HPLC-DAD combined with principal component analysis (PCA) and multi-ingredient quantitative analysis. RESULTS A variety of metabolites with high contents were produced after 0.5 h of intestinal digestion and colonic fermentation 0.5 h. Application of PCA to HPLC data showed the obvious separation of colonic fermentation 0.5 h stage samples from other colonic fermentation stages samples (24, 48 and 72 h). Addition? ally, non-digestion and saliva digestion stage samples clustered together, and there was obvious separation between intestinal digestion samples and gastric digestion samples. The contents of epimedium C, icariin and baohuside I all increased significantly after intestinal digestion [58.70 ± 7.08, 47.15 ± 5.68 and (12.78 ± 0.55) mg · g-1] compared with gastric digestion [29.00 ± 5.65, 17.40 ± 4.55 and (2.77 ± 0.19) mg·g-1]. There were significant differences between sample after 0.5 h of colonic fermentation [64.22 ± 9.32, 51.26 ± 6.33 and (16.68 ± 3.19) mg·g-1] and other time points (24, 48 and 72 h) in components and the contents of active ingredient, and the content of these components all decreased with the fermentation time. The ability of scavenging ABTS free radicals [IC50=(0.29 ± 0.02) g · L-1] increased significantly compared with gastric digestion [(1.57 ± 0.02) g·L-1], and after 0.5 h of colonic fermentation, the ability also increased significantly. CONCLUSION Gastrointestinal digestion had a significant impact on the contents of active components in Epimedium, and the metabolism of these components mainly occurred in the colon. The intestinal digestion and colonic fermentation significantly improved the anti-ABTS activity of epimedium.