白苏叶挥发油超临界CO_(2) 萃取工艺优化、成分分析及抗氧化活性研究

Extraction process optimization,composition analysis of volatile oil from Perilla frutescens leaf and its antioxidant activity

目的:优化超临界CO_(2)萃取白苏叶挥发油的提取工艺,提升白苏叶的实用价值。方法:通过单因素试验(萃取压力、萃取温度、萃取时间和CO_(2)流量)和响应面分析预测白苏叶挥发油提取的最优参数,并通过气相色谱—质谱(GC-MS)分析白苏叶挥发油的化学成分,同时利用清除DPPH·和·OH能力评价其抗氧化活性。结果:在萃取压力27 MPa、萃取温度40℃下,连续萃取2.0 h,挥发油提取率可达(2.71±1.19)%,较水蒸气蒸馏法提取率高67%,能一定程度降低过氧化值和酸值。从白苏叶挥发油中鉴定出51种化学物质,占全油的98.49%,主要成分为酯类、醇类和烯类化合物。抗氧化试验表明白苏叶挥发油对DPPH·和·OH具有较强的清除能力,且存在明显的量效关系。结论:超临界CO_(2)萃取的白苏叶挥发油,主要成分为酯类、醇类和烯类化合物,具有较强的抗氧化能力。

Objective:The research aimed to optimize the supercritical CO_(2) extraction process of volatile oil from Perilla frutescens leaf and enhance the practical value of Perilla frutescens.Methods:The optimal parameters for extraction of volatile oil from Perilla frutescens leaf was predicted by single factor experiments(extraction pressure,extraction temperature,extraction time and CO_(2)flow)and response surface methodology.Then the gas chromatography-mass spectrometry(GC-MS)was applied to determine the chemical components of volatile oil from Perilla frutescens leaf.In addition,its antioxidant activity was explored with the scavenging capacity on DPPH·and·OH radicals.Results:The optimal process parameters of supercritical CO_(2) extraction for volatile oil from Perilla frutescens leaf were founded to be at 27 MPa,40℃and 2 h,the actual yield was(2.71±1.19)%,which was 67%higher than the vapor distillation under the same extraction time and reduce the peroxide value and acid value.The 51 chemical compounds were identified in the volatile oil from Perilla frutescens leaf and accounted for 98.49%of all the peak area,which contained lipids,alcohols and olefins.The volatile oil of Perilla frutescens leaf had strong scavenging effect on DPPH·and·OH radicals,and the scavenging capacity had a significant positive correlation with oil concentration.Conclusion:In this study,the supercritical CO_(2) extraction of volatile oil from Perilla frutescens leaf were mainly composed of lipids,alcohols and olefins,which has strong antioxidant capacity.