Hao Xin, Xie Jiahong, Li Yuting, Chen Wei
Department of Food Science and Nutrition, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
Ningbo Research Institute, Zhejiang University, Ningbo 315100, China.
Food Funct. 2022 Mar 7;13(5):2618-2630. doi: 10.1039/d2fo00179a.
Anthocyanins are natural products that display diverse bioactivities but are limited in their applications by low stability and bioavailability. Acylated anthocyanins are found to possess higher stability, while their bioactivities are still obscure. In this study, acetylation of pelargonidin-3--glucoside (Pg3G) was catalyzed by lipase B (CALB) for the first time, with a conversion rate up to 88.77% over 48 h. The acetylated product was identified as pelargonidin-3--(6''-acetyl)-glucoside and its properties were detected. Notably, acetylated Pg3G (Ace Pg3G) possessed better thermostability and lipophilicity than Pg3G, indicating a longer retention time at physiological pH and facilitating penetration into the lipophilic medium as well as the cell membrane. Most importantly, Ace Pg3G exerted better alleviation effects against HO-induced oxidative hepatic damage than parent Pg3G activating the Nrf2/ARE signaling pathway and upregulating the expressions of the downstream phase II detoxification enzymes GCLC and HO-1, thereby reversing redox imbalance and enhancing cell survival. Overall, our research unveiled the better health benefits of Ace Pg3G and also provided new insights about the applications of acetylated anthocyanins in food, cosmetic, and pharmaceutical products.
花青素是具有多种生物活性的天然产物，但由于稳定性和生物利用度较低，其应用受到限制。酰化花青素具有较高的稳定性，但其生物活性仍不明确。在本研究中，首次利用脂肪酶B（CALB）催化天竺葵素-3-葡萄糖苷（Pg3G）的乙酰化反应，48小时内转化率高达88.77%。对乙酰化产物进行了鉴定，并检测了其性质。值得注意的是，乙酰化Pg3G（Ace Pg3G）比Pg3G具有更好的热稳定性和亲脂性，这表明其在生理pH值下的保留时间更长，有利于渗透到亲脂性介质以及细胞膜中。最重要的是，与母体Pg3G相比，Ace Pg3G对HO诱导的氧化肝损伤具有更好的缓解作用，它激活Nrf2/ARE信号通路，上调下游II期解毒酶GCLC和HO-1的表达，从而逆转氧化还原失衡并提高细胞存活率。总体而言，我们的研究揭示了Ace Pg3G具有更好的健康益处，也为酰化花青素在食品、化妆品和药品中的应用提供了新的见解。
