Changes in Active Ingredients and Antioxidant Capacity of Phyllanthus emblica Linn and Its Ethanol Extract in Vitro Simulated Digestion

To compare the differences between lyophilized powder (LP) and ethanol extract (EE) of Phyllanthus emblica Linn. (PE) in vitro digestion (oral cavity, gastric area, small intestine, and large intestine), this study identified the main components of PE and then compared total phenolic acids (TPA), total flavonoids (TFA) and antioxidant capacity before and after digestion. Results showed that both LP and EE of PE were rich in polyphenols and flavonoids. LP contained higher bound polyphenols than EE, while EE contained higher free polyphenols than LP. Before digestion, TPA and TFA of the LP were 5.40±0.07 mg GAE/mL and and 1.48±0.15 mg RT/mL, respectively. While the TPA and TFA of the EE were 3.65±0.05 mg GAE/mL and 14.80±0.74 mg RT/mL, respectively. After digestion, TPA of the LP and EE was significantly lower than before (P<0.05). However, the TFA was higher than before after digestion in oral cavity. Before digestion, the EE showed significantly lower scavenging capacities on ABTS^＋, DPPH radicals, and Fe³⁺ reduction than the LP. However, after digestion, the antioxidant ability of the EE was significantly higher than LP (P<0.05). Correlation analysis of the TPA and TFA with antioxidant capacity showed a significant positive correlation (P<0.05). In conclusion, after digestion in vitro, the active ingredients and antioxidant capacity of the LP and EE of PE changed significantly. The EE had stronger antioxidant capacity compared with the LP. It is suggesting that PE products after extraction treatment may have higher health benefits.