沙棘叶提取物的体外抗氧化及乙酰胆碱酯酶抑制能力

In vitro antioxidant activities and acetylcholinesterase inhibition ability of sea buckthorn (Hippophae rhamnoides L.) leaves extracts

摘要:

以沙棘叶为原料，以DPPH?清除能力、总还原力为指标，评估沙棘叶提取物的体外抗氧化活性，并以沙棘叶提取物对乙酰胆碱酯酶的抑制能力为指标，考察其成为乙酰胆碱酯酶抑制剂的潜力。研究结果表明：5种不同乙醇体积分数的（40%、50%、60%、70%、80%）沙棘叶提取物均有较好的抗氧化活性与对乙酰胆碱酯酶抑制能力。以60%乙醇提取的沙棘叶提取物的DPPH?清除率、总还原力及乙酰胆碱酯酶抑制能力最强，分别为（85.80±1.39）%，3.06±0.18，（97.14±0.809）%，可作为抗氧化剂与乙酰胆碱酯酶抑制剂。筛选后的沙棘叶提取物对乙酰胆碱酯酶有较强的抑制能力，半数抑制质量浓度（IC50）值为（1.086±0.144）mg/mL，并且根据酶的抑制动力学分析得出对乙酰胆碱酯酶是竞争性大于非竞争性的混合可逆抑制类型。AutoDock分子对接结果也表明，沙棘叶活性成分与乙酰胆碱酯酶具有一定的对接亲和力。剂效相关性分析表明沙棘叶提取物的抗氧化、酶抑制活性与功能成分之间均存在良好的正相关性（P<0.05），沙棘叶提取物中起主要抗氧化与酶抑制作用的成分为多酚类化合物.

Abstract:

The in vitro antioxidant activity of Hippophae rhamnoides L. leaves extracts was evaluated using DPPH? scavenging capacity and total reducing power as indicators, and its ability to be an acetylcholinesterase inhibitor was examined by the inhibition ability of Hippophae rhamnoides L. leaves extracts on acetylcholinesterase. The results showed that five different ethanol volume fractions of (40%, 50%, 60%, 70%, and 80%) Hippophae rhamnoides L. leaves extracts showed good antioxidant activity and acetylcholinesterase inhibitory capacity. The DPPH? scavenging rates, total reducing power, and acetylcholinesterase inhibitory capacity of Hippophae rhamnoides L. leaves extracts with 60% ethanol reached maximum values of (85.80±1.39) %, 3.06±0.18, and (97.14±0.809) % as antioxidants and acetylcholinesterase inhibitors. The screened Hippophae rhamnoides L. leaves extracts showed strong inhibitory ability against acetylcholinesterase with a half inhibitory concentration（IC50） of (1.086±0.144) mg/mL and a mixed reversible type of inhibition against acetylcholinesterase based on the kinetic analysis of enzyme inhibition that was more competitive than non-competitive. The results of AutoDock molecular docking also indicated that the active ingredients of Hippophae rhamnoides L. leaves have a certain docking affinity with acetylcholinesterase. Dose-effect correlation analysis showed a favorable correlation (P<0.05) between the antioxidant and enzyme inhibitory activities of Hippophae rhamnoides L. leaves extracts and the functional components, and it showed that polyphenols played a major role in antioxidant activity and enzyme inhibitors.