Anti-proliferation activities of Oryza sativa L. anthocyanins-Hohenbuehelia serotina polysaccharides complex after in vitro gastrointestinal digestion

Abstract

In order to improve the bioavailability of Oryza sativa L. anthocyanins, we fabricated Oryza sativa L. anthocyanins-Hohenbuehelia serotina polysaccharides (OSA-HSP) complex and investigated its anti-proliferation activities taking into account its changes along simulated gastrointestinal digestion in vitro. Results showed that OSA mainly composed by delphinidin, cyanidin, petunidin, malvidin and their derivatives was combined with HSP through electrostatic interaction. OSA-HSP complex belonged to non-crystalline substance, and had compact and laminar structural characteristics. Under simulated gastrointestinal digestion, OSA-HSP complex significantly prevented the degradation of anthocyanins, and presented sustain release effect. However, the anti-proliferation activities of OSA-HSP complex digested by different gastrointestinal process were remarkably changed, especially after small intestinal digestion. HeLa cells treated with OSA-HSP complex exhibited pro-apoptosis characteristics by triggering endogenous mitochondrial apoptosis pathway through activating the expressions of Bax, cytochrome c and Caspase-3 as well as inhibiting the expression of Bcl-2. These findings provided new insight to improve the bioavailability of anthocyanins in functional foods and tumor therapy.

Keywords: Anthocyanins; Anti-proliferation activity; Gastrointestinal digestion; Polysaccharides.