葡萄籽原花青素(GSP),作为一种天然抗氧化剂,有很大的潜力发展成为一种降脂药,但其低的亲脂性和稳定性极大地限制了其应用。在这项研究中,开发了一种酶促酯化策略,将脂肪酸链引入GSP,成功合成了一系列新的GSP衍生物。结果表明,GSP的转化率高达85%,GSP衍生物的TAG抑制率高达35%。GSP衍生物的结构通过UPLC-MS/MS鉴定,和七种衍生物被证实为儿茶素-3'-O-月桂酸酯,表儿茶素-3\'-O-月桂酸酯,表儿茶素没食子酸酯-3″,5″-二-O-月桂酸盐,表儿茶素没食子酸盐-3',3″,5″-三-O-月桂酸盐,原花青素B1-3',3″-二-O-月桂酸盐,原花青素B2-3',3″-二-O-月桂酸和原花青素C1-3',3″,3-三-O-月桂酸酯的NMR。GSP衍生物对脂质积累表现出更高的抑制作用,胞内TAG和TC比亲本GSP。这些结果表明GSP衍生物具有作为在食品工业中使用的降脂剂的潜力。
Grape seed proanthocyanidin (GSP), as a natural antioxidant, has great potential to be developed into a lipid-lowering agent, but its low lipophilicity and stability greatly limit its application. In this study, an enzymatic esterification strategy was developed to introduce fatty acid chains into GSP, resulting in the successful synthesis of a series of new GSP derivatives. The results showed that up to 85% conversion of GSP and 35% TAG inhibition rate of GSP derivatives were achieved. The structures of GSP derivatives were identified by UPLC-MS/MS, and seven derivatives were confirmed as catechin-3\'-O-laurate, epicatechin-3\'-O-laurate, epicatechin gallate-3″,5″-di-O-laurate, epicatechin gallate-3\',3″,5″-tri-O-laurate, procyanidin B1-3\',3″-di-O-laurate, procyanidin B2-3\',3″-di-O-laurate and procyanidin C1-3\',3″,3‴-tri-O-laurate by NMR. GSP derivatives exhibited higher inhibitory effects on lipid accumulation, intracellular TAG and TC than parent GSP. These results indicate that GSP derivatives have potential as lipid-lowering agents for utilization in the food industry.