油茶半微量种仁中油脂和茶皂素含量的同步提取测定

Simultaneous extraction and determination of oil and tea saponin content of semimicro quantities seed kernels of Camellia oleifera

【目的】油脂和茶皂素是油茶种仁的重要成分,建立半微量油茶种仁油脂和茶皂素同步提取测定方法,为油茶品质研究和良种选育提供科学依据。【方法】选择半微量油茶种仁,使用脂肪提取试剂盒提取其中的油脂和茶皂素,研究提取温度(20~40℃)、提取时间(3~20 min)和提取料液比(1∶10~1∶30 g/mL)3种单因素条件对油脂和茶皂素提取率的影响,初步筛选出每个因素的最佳值。通过响应面实验设计方法,优化确定提取条件和建立回归模型,预测得出该优化条件下油脂和茶皂素的提取率,并进行线性、精密度、重复性及最低投入量等方面研究该模型的拟合度。同时从样品需要量、测定成分、准确度、提取时间方面与传统方法进行比较。【结果】油脂和茶皂素综合最佳提取条件为:温度31.35℃,时间10.41 min,料液比为1∶21.9 g/mL,同时得到的油脂和茶皂素的提取率分别为99.11%和97.73%。6次测定标准偏差为油脂1.34%,茶皂素1.74%,各脂肪酸的加标回收率为95.64%~100.92%,茶皂素为98.51%。本方法可精确测定最低样品量≤50 mg且含油率为26.37%~65.26%、茶皂素含量为7.69%~11.51%的油茶种仁的油脂和茶皂素含量;测定10例常量油茶种仁样品的油脂和茶皂素含量,本方法与经典方法无统计学差异。【结论】与传统方法比较,本方法可实现油脂和茶皂素的同步提取和精确测定,样品提取时间短,灵敏度高,所需要样品量少(≤50 mg),可为油茶半微量种仁中油脂和茶皂素的提取测定提供科学方法。

【Objective】Lipid and tea saponin are important components of Camellia oleifera seed kernels.This study intends to establish a method for simultaneous determination of lipid and tea saponin in semimicro quantities of C.oleifera seed kernels,which will provide scientific basis for quality research of tea oil and breeding of improved varieties.【Method】Lipid and tea saponin were extracted from semimicro quantities C.oleifera seed kernels by fat extraction kit.The effects of three single factors of extraction temperature(20-40℃),extraction time(3-20 min)and extraction material to liquid ratio(1:10-1:30 g/mL)on the extraction rate of oil and tea saponin were studied,and the optimal value of each factor was screened out respectively.Through the response surface design method,the extraction conditions were optimized and the regression model was established.The extraction rate of lipid and tea saponin under the optimized conditions was predicted and the fitting degree of the model was studied in terms of linearity,precision,repeatability and minimum input.At the same time,the sample requirement,determination composition,accuracy and extraction time were compared with the traditional method.【Result】The optimal extraction conditions of lipid and tea saponin were as follows:temperature 31.35℃,time 10.41min,material to liquid ratio 1:21.9 g/mL.The extraction rates of lipid and tea saponin were 99.11%and 97.73%,respectively.The standard deviations of six determinations were 1.34%for lipid and 1.74%for tea saponin.The recovery rate of fatty acids was ranged from 95.64%to 100.92%,and the recovery rate for tea saponin was 98.51%.The method can accurately determine the lipid and tea saponin contents of C.oleifera seed kernels with the minimum sample quantity≤50 mg,lipid content of 26.37%-65.26%and tea saponin content of 7.69%-11.51%.There was no statistical difference between this method and classical method in the determination of lipid and tea saponin content in 10 samples of C.oleifera seed kernels.【Conclusion】Compared with the traditional method,this method has the advantages of short extraction time,high sensitivity and less sample quantity(≤50 mg).It can realize the simultaneous and accurate determination of lipid and tea saponin and provide a scientific method for the simultaneous extraction and determination of lipid and tea saponin in semimicro quantities seed kernels of C.oleifera.