基于茚三酮比色法测定闽产细叶石仙桃总氨基酸含量

Detection of total amino acids of Pholidota cantonensis Rolfe.from Fujian province by ninhydrin colorimetric method

目的:优化溶剂回流提取-茚三酮比色法测定福建省不同产地细叶石仙桃中总氨基酸含量。方法:以甘氨酸为对照品,采用茚三酮比色法测定细叶石仙桃中总氨基酸含量;考察不同影响因素对茚三酮法测定细叶石仙桃总氨基酸含量的影响,确定最佳检测条件;在单因素实验基础上,采用L9(34)正交试验考察溶剂用量、溶剂浓度、提取时间及提取次数对细叶石仙桃中总氨基酸提取工艺的影响,并以其为考察指标,优化筛选最佳提取工艺。结果:最佳检测条件为测定波长568 nm、2%茚三酮溶液用量3.0 mL、缓冲液pH值6、缓冲液用量2.0 mL、水浴加热温度80℃、水浴加热时间40 min;最佳提取条件为乙醇浓度85%,乙醇用量35.0 mL,提取时间60 min,提取2次。在所收集到的福建省4个产地的细叶石仙桃中总氨基酸含量由高到低依次为永泰县、上杭县、屏南县、永春县。结论:优选的提取工艺稳定可行,建立含量测定方法简便、准确、重复性好,为细叶石仙桃的质量评价和进一步开发利用提供依据。样品中以永泰县所产的细叶石仙桃质量最佳。

Objective:To optimize the detection condition of amino acids in Pholidota cantonensis Rolfe.from different producing areas of Fujian province by solvent reflux extraction and ninhydrin colorimetric method.Methods:The content of total amino acids was determined by ninhydrin colorimetric method with glycine as reference;the effect of different influence factors on detection were studied to determine the optimal detection conditions;on the basis of single factor experiment,L9(34)orthogonal test was used to investigate the effects of solvent dosage,solvent concentration,extraction time and extraction times on the extraction process of total amino acids from Pholidota cantonensis.The optimal extraction process was optimized based on these indexes.Results:The optimum detection conditions were:wavelength 568 nm,ninhydrin(2%)volume 3 mL,pH 6,buffer solution 2 mL,water bath heating temperature 80℃and heating time 40 min.The optimal ultrasonic extraction conditions were as follows:alcohol concentration 85%,alcohol amount 35 mL,extraction time 60 min,and twice extraction.The contents of total amino acids in four different producing areas in Fujian province were as follows:Yongtai county,Shanghang county,Pingnan county and Yongchun county.Conclusions:The ninhydrin colorimetric method is simple,accurate,reliable and reproducible.The optional extraction is stable and feasible,which can provide a basis for quality evaluation control,the determination and further development of Pholidota cantonensis.In the collected samples,the best quality of Pholidota cantonensis from Yongtai county is obtained.