桂圆中儿茶素类成分提取及HPLC与红外光谱法分析

Study on extraction and determination of contents of catechins by the methods of HPLC and FTIR spectroscopy from longan

目的:研究了桂圆皮中儿茶素类成分超声波提取工艺,并对桂圆皮、肉及核中儿茶素类成分没食子酸(GA)、儿茶素(-C)、表没食子儿茶素没食子酸酯(EGCG)、表儿茶素(EC)和表儿茶素没食子酸酯(ECG)进行定性、定量分析。方法:采用Box-Behnken Design实验考察甲醇体积分数、料液比和桂圆皮粉碎度三因素对桂圆皮中儿茶素类成分提取的影响,优化最佳提取工艺参数。用HPLC与红外光谱法对桂圆中儿茶素类成分进行分析和定量,确定其儿茶素类成分类型及含量。结果:最佳提取工艺参数为甲醇体积分数51%、料液比1∶30g/m L和桂圆皮粉碎度90目。桂圆皮儿茶素单体类型及含量:EC为0.786mg/g,ECG为0.33mg/g,-C为0.246mg/g,EGCG为0.163mg/g,GA为0.0387mg/g;桂圆核:EC为3.19mg/g,ECG为1.019mg/g,GA为0.385mg/g,EGCG为0.178mg/g。结论:红外光谱法证实:桂圆皮、核含有儿茶素类单体成分或其单体的聚合体。为桂圆儿茶素类成分有效开发提供一定的理论基础。

Objective：To study the ultrasonic-assisted extraction of catechins from longan and identification and quantification of the contents of catechins,including gallic acid,catechin,epigallocatechin-gallate,epicatechin and epicatechin-gallate,were studied from peel,flesh and seed of longan. Methods ：Box-Behnken design（BBD） was applied to evaluate the effects of three independent variables（methanol concentrations,the ratio of solvent to material and the smash degree） on total catechins of of longan peel. Identification and quantification of the contents of catechins were investigated by the methods of HPLC and FTIR spectroscopy in longan.Results：The results showed that the optimal conditions were as follows：methanol concentrations were 51%,the ratio of solvent to material was 1∶30g/m L and the smash degree was 90 mu with the ultrasonic extraction method.The contents of catechins showed that epicatechin was 0.786mg/g,epicatechin-gallate was 0.33mg/g,catechin was 0.246mg/g,epigallocatechin-gallate was 0.163mg/g and gallic acid was 0.0387mg/g in longan peel and other results showed that epicatechin was 3.19mg/g, epicatechin-gallate was 1.019mg/g, gallic acid was0.385mg/g and epigallocatechin-gallate was 0.178mg/g in longan seed, respectively. Conclusion ： It was confirmed that different structural units of catechins and polymeric compounds by means of FTIR spectroscopy in longan. These result set the theoretical foundation for the development and utilization of catechins from longan.