Abstract:The bioaccessibility and anti-tumor cell proliferation activity of Citrus fruits (Citrus reticulata, Navel orange and Kumquat) polyphenol were evaluated by simulated gastrointestinal digestion. After the Citrus fruits were simulated for gastrointestinal digestion, the release of major polyphenols was determined by high performance liquid chromatography, and the activity of Citrus fruit extracts against HepG2 cells was determined by methylene blue method. The results showed that Citrus polyphenols with a large release amount (>20 mg/kg FW) were neohesperidin, phlorizin, naringenin, vanillic acid, protocatechuic acid, and the like. Simulated gastric digestion promoted the release of phlorizin, vanillic acid, and protocatechuic acid, and most of the polyphenols detected significantly degraded during intestinal digestion. After simulating gastrointestinal digestion, the Citrus fruits concentrations that produced cytotoxicity were significantly reduced. The cells survival rates were 65.46%, 37.20%, 24.19% and 21.32%, 43.52%, 12.31%, respectively, after HepG2 cells were treated with simulated gastric digestion and simulated intestine digestion of the Citrus reticulata, Navel orange and Kumquat extracts (Concentrations of 84.56, 93.74, 32.26 mg/mL and 121.23, 107.14, 40.03 mg/mL, respectively) for 72 hours. This suggests that the simulated gastric digestion promotes the release of active substances against HepG2 cell proliferation.
