杜香精油的酶辅助提取工艺及抗氧化活性研究

Study on the enzyme-assisted extraction process of essential oil from Ledum palustre L.and its antioxidant activity

为探索一种绿色、高效、低能耗的方法来提取杜香(Ledum palustre L.)精油,采用酶辅助水蒸气蒸馏法提取杜香精油,利用气相色谱法-质谱法联用(gas chromatography-mass spectrometry,GC-MS)分析比较其化学成分与常规水蒸气蒸馏法的区别,并研究杜香精油的抗氧化活性。结果表明,酶辅助水蒸气蒸馏法的最佳工艺条件:料液比1∶20 g/mL、酶的pH 5.5、酶解时间4 h、酶解温度55℃、酶浓度1.5%、提取时间1.5 h,在此条件下,杜香精油提取率为1.71%,与水蒸气蒸馏法相比,杜香精油的提取率提高了67.65%;酶辅助提取所得的杜香精油化学成分有53种,水蒸气蒸馏法提取所得精油化学成分有44种,表明酶解可以使精油更好地释放出来,使酶辅助提取的杜香精油化学成分更丰富。在抗氧化实验中,酶辅助提取的杜香精油对DPPH自由基、ABTS自由基和羟基自由基的清除能力较水蒸气蒸馏法提取的杜香精油强,总体上具有明显的抗氧化活性并有良好的量效关系。本研究将为杜香精油的大规模生产提供可靠的工艺参数,并为评价其抗氧化活性提供基础数据和参考。

To explore a green,efficient and low-energy method for extracting essential oil from Ledum palustre L.,the enzyme-assisted water vapor distillation method was used to extract essential oil,and the chemical composition was analyzed and compared with the conventional water vapor distillation method by gas chromatography-mass spectrometry,and the antioxidant activity of essential oil was studied as well.The results showed that the optimal process conditions of the enzyme-assisted water vapor distillation method are as follows:the material-to-liquid ratio is 1∶20 g/mL,the pH of the enzyme is 5.5,the enzymolysis time is 4 h,the enzymolysis temperature is 55℃,the concentration of the enzyme is 1.5%,and the extraction time is 1.5 h.Under this condition,the extraction rate of essential oil from L.palustre is 1.71%.Compared with water vapor distillation,the extraction rate of essential oil increased by 67.65%.There are 53 kinds of chemical components of essential oil from L.palustre obtained by enzyme-assisted extraction,and only 44 kinds of chemical components of essential oils extracted by water vapor distillation method.It is shown that enzymolysis can make the essential oil better released,so that the chemical composition of the enzyme-assisted extraction of essential oil is abundant.In the antioxidant experiment,the essential oil extracted by enzyme assisted extraction had stronger scavenging ability on DPPH free radical,ABTS free radical and hydroxyl free radical than the essential oil extracted by steam distillation.In general,the essential oil extracted by enzyme assisted extraction had obvious antioxidant activity and a good dose-response relationship.This study will provide reliable process parameters for the large-scale production of essential oil,and provide basic data and reference for evaluating its antioxidation.