体外模拟胃肠消化对不同热处理荷叶中酚类物质释放量及抗氧化活性的影响

为探讨体外模拟胃肠消化对不同热处理荷叶中酚类物质释放及抗氧化活性的影响,采用真空微波、湿热蒸汽和煮沸3种热加工方式和体外模拟胃肠消化对不同生长期荷叶进行处理。结果表明,荷叶中酚类物质的释放与荷叶生长过程中荷叶直径大小呈正相关,其中直径为56 cm的荷叶总酚释放量最高。此外,在不同消化方式不同热处理下,真空微波干燥处理的荷叶(V56)总酚和总黄酮释放量均最高,且其FRAP、ABTS抗氧化能力也最强。与对照组相比,模拟胃液处理显著提高了真空微波热处理组荷叶的总酚释放量,显著降低了煮沸处理组荷叶的总酚释放量,对湿热蒸汽处理组荷叶的总酚释放量无影响,而模拟胃液处理均显著降低了不同热处理组荷叶的总黄酮释放量;模拟肠液处理均显著增加了不同热处理组荷叶的总酚和总黄酮释放量。与对照组相比,模拟胃液消化显著提高了真空微波处理组和湿热蒸汽处理组荷叶的FRAP抗氧化能力,降低了煮沸处理组荷叶的FRAP抗氧化能力;模拟肠液消化显著提高了真空微波组荷叶的FRAP抗氧化能力。模拟胃液消化中真空微波处理组的ABTS抗氧化能力与对照相比有所降低,而模拟肠液消化显著提高了3种热加工处理组荷叶的ABTS抗氧化能力。本研究结果为荷叶的开发利用提供了技术支撑和理论依据。

Effects of Simulated in Vitro Gastrointestinal Digestion on Phenolics Release and Antioxidant Activity in Different Heat Treatment Lotus Leaves

In order to study the effects of heating treatments on the phenolic compounds release and antioxidant activity of lotus leaf during simulated digestion, vacuum microwave, hygrothermal steam and boiling treatments on different growth stages lotus leaf were investigated. The results showed that the release of phenolic substances of lotus leaves was positively correlated with the diameter of the sample, the highest release of total phenolic content (TPC) of 56 cm leaves diameter. Under the different simulated gastric fluid treatment and different heat treatment, the total phenolic contents, total flavonoid contents, the antioxidant capacity of FRAP ( ferric ion reducing antioxidant power) and the ABTS (2, 2?-azino-bis(3-ethylbenzthiozoline-6)-sulphonic acid) radical scavenging was the highest in V56 lotus leave by vacuum microwave. Compared with the control group, the TPC release of lotus leaves under vacuum microwave treatment were higher for simulated gastric fluid treatment. But the TPC release of boiling treated samples was lower than control group. There was no change in the release of the lotus leaf TPC treated by hygrothermal steam treatment of simulated gastric fluid. However, the total flavonoid contents (TFC) release of different heating groups was lower than control group. Both the TPC and TFC release of lotus leaves treated by different heating methods were increased under the simulated intestinal fluid treatment. The FRAP antioxidant capacities of lotus leaves treated by vacuum microwave and hygrothermal steam treatments were increased after simulated gastric fluid digestion, but the FRAP antioxidant capacities of lotus leaves treated by boiling were reduced. The FRAP antioxidant capacities of lotus leaves treated by vacuum microwave were increased after simulated intestinal fluid digestion. The ABTS radical scavenging of simulated gastric fluid digested microwave treated lotus leaves were lower than that treated by deionized water. However, compared with the control group, the ABTS radical scavenging of lotus leaves treated by three different heating treatments were all increased after simulated intestinal fluid digestion. The results of the present study could provide technical support for the utilization of lotus leaf.