采用HepG2细胞模型评价酒醅中短肽VPD和KGP的抗氧化活性

Evaluation on the Antioxidant Activity of VPD and KGP in Jiupei by HepG2 Cells Model

摘要:

本研究针对前期实验从白酒酒醅中分离、提取和鉴定出的两种短肽Val-Pro-Asp (VPD) 和Lys-Gly-Pro (KGP) 的细胞水平抗氧化活性进行研究。以AAPH诱导氧化损伤的人体肝癌细胞(Human hepatoma cell, HepG2 cell)为模型，测定短肽对细胞内活性氧（ROS）含量、抗氧化酶的活性等指标。结果表明，VPD和KGP具有细胞内抗氧化活性，其作用机制体现在可以显著降低细胞内ROS含量，提高过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)和超氧化物歧化酶(SOD)三种酶的活力以及还原型谷胱甘肽(GSH)的含量，同时也能够通过降低细胞内脂质过氧化水平，如丙二醛(MDA)的含量来保护细胞免受氧化损伤，并且两种多肽的抗氧化能力随着浓度的上升基本呈现一定的增强趋势。综上所述，两种短肽在细胞水平具有一定的抗氧化能力，这为后续通过调整白酒蒸馏工艺条件，从而提高酒醅中功能性多肽进入白酒中的含量提供了可能。

Abstract:

In this study, the cells-level antioxidant activities of two peptides, Val-Pro-Asp (VPD) and Lys-Gly-Pro (KGP), which were extracted, isolated and identified from Jiupei of Baijiu, were studied. The antioxidative activities of two peptides were evaluated by measuring their effects on intracellular reactive oxygen species (ROS) content, activity of antioxidant enzymes and other indexes in AAPH induced oxidative-damaged human hepatoma cells (HepG2 cells) model. The result showed that VPD and KGP possessed intracellular antioxidant activity. The mechanism of the action was that they can significantly decrease the content of ROS in cells, increase the activity of three enzymes of catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and reduced the glutathione (GSH) content. At the same time, they can also decrease the level of lipid peroxide in cells e.g. MDA content to protect cells from oxidative damage and capacity of two peptides basically increased with the rise of concentration. This provides the possibility to improve the contents of functional peptides from Jiupei into Baijiu by optimizing the distillation condition.