为了确定荷叶抗氧化活性的有效部位以及进一步提高该有效部位抗氧化活性，本文采用系统溶剂法对荷叶抗氧化活性进行了测定和分析，进而采用盐酸对该有效部位进行了水解处理。结果表明，在不同极性部位中，弱极性部位-乙酸乙酯相超氧阴离子、羟自由基清除能力及总抗氧化力最强，为荷叶抗氧化活性的有效部位。采用盐酸水解能显著性提高该有效部位抗氧化能力（P<0.05或P<0.001）。与水解前相比，该有效部位水解后总还原力、DPPH清除率、FRAP抗氧化能力（OD593）、总抗氧化力（OD695）和羟自由基清除率增幅分别为48.52%、58.22%、64.3%、22.15%和100.48%，超氧阴离子清除率从（42.43±1.23）%提高到（44.97±0.22）%。结果证明，荷叶抗氧化活性物质主要是存在于有效部位-乙酸乙酯相的弱极性化合物；酸水解是进一步提高其抗氧化活性的有效手段。本文为后续对荷叶抗氧化功能食品研究与开发提供了依据。

The aim of this study was to identify and further improve the antioxidant activity of the effective fraction in lotus leaves. Lotus leaf fractions were prepared by systematic solvent extraction, and antioxidant activity was measured to identify the effective antioxidant fraction, which was then hydrolyzed by using hydrochloric acid. The results showed that among all fractions with different polarities, the low-polar fraction (ethyl acetate fraction) showed the strongest antioxidant activity in terms of percentage of hydroxyl radicals and superoxide anions scavenged and total antioxidant capacity. Therefore, this fraction was identified as the effective antioxidant fraction of lotus leaf. The antioxidant capacity of the effective fraction was significantly improved by hydrochloric acid hydrolysis (P < 0.05 or P < 0.001). Compared with the effective fraction before hydrolysis, the total reducing power, percentage of 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenged, ferric-reducing antioxidant power (FRAP, OD593), total antioxidant power (OD695nm), and percentage of hydroxyl radicals scavenged of the post-hydrolytic fraction showed an improvement by 48.5%, 58.22%, 64.3%, 22.15%, and 100.48%, respectively. The percentage of superoxide anion radicals scavenged showed an improvement from 42.43% ± 1.23% to 44.97% ± 0.22%. The results demonstrated that the active antioxidants of lotus leaf comprised of mainly low-polar compounds in the effective fraction (ethyl acetate fraction), and hydrochloric acid hydrolysis was an effective approach to improve the antioxidant capacity of this fraction. This study provides a basis for further research and development of functional foods by using lotus leaf.