摘要
该文建立柱前衍生-高效液相色谱法测定不同干燥方式下地参中17种氨基酸的含量.以异硫氰酸苯酯(phenyl isothiocyanate,PITC)为衍生试剂,色谱柱为V enusil-AA(4.6 mm × 250 mm,5 μm)氨基酸分析专用柱,流动相为0.1 mol/L乙酸钠-80％乙腈溶液(冰醋酸调至pH 6.5),梯度洗脱,流速0.8 mL/min,检测波长254 nm,柱温35℃.17种氨基酸在各自质量浓度的线性范围内关系良好(r≥0.999 0),平均加标回收率为96.79％～103.94％,其相对标准偏差(relative standard deviation,RSD)为0.73％～2.97％.12种干燥方式的地参氨基酸总量存在差异(P＜0.05),为13.085～28.988 mg/g,其中真空冷冻-80℃下含量最高为28.988 mg/g,12种干燥方式均检出17种氨基酸,包括7种必需氨基酸和9种药用氨基酸,必需氨基酸占总氨基酸(essential amino acids/total amino acids,EAA/TAA)的 31.80％～36.51％,平均值为 34.36％;药用氨基酸占总氨基酸(medicinal amino acids/TAA,MAA/TAA)的57.72％～67.84％,平均占比63.12％.通过主成分分析提取3个主成分,其累计方差贡献率达92.83％,综合评分为真空冷冻-80 ℃品质最优;聚类分析将12种干燥方式分为三类,真空冷冻-80℃和阴干含量较高.该方法操作简单、分离效果好,适用于同时测定地参中17种氨基酸类成分含量,12种干燥方式中真空冷冻-80℃下含量最高,营养价值较高,为地参的加工提供理论和实践依据.
Abstract
This study established a pre-column derivatization-high performance liquid chromatography(HPLC)method for determi-ning the content of 17 amino acids in Lycopus lucidus Turcz.var.hirtus Regel under different drying methods.The experiment used phenyl isothiocyanate(PITC)as the derivatization reagent,Venusil-AA(4.6 mm × 250 mm,5 µm)amino acid analysis column as the chrom-atographic column,and the mobile phase was 0.1 mol/L sodium acetate-80％acetonitrile solution(glacial acetic acid adjusted to pH 6.5),A gradient elution was used with a flow rate of 0.8 mL/min,a detection wavelength of 254 nm,and a column temperature of 35 ℃.Results showed that the 17 amino acids had good linearity within their respective mass concentration ranges(r≥ 0.999 0),with an average recovery rate of 96.79％to 103.94％and a relative standard deviation(RSD)of 0.73％to 2.97％.After being treated with 12 drying methods,there were differences in the total amount of amino acids in Lycopus lucidus Turcz.var.hirtus Regel(P＜0.05),ran-ging from 13.085 to 28.988 mg/g.Among them,with the highest content was 28.988 mg/g under vacuum freezing at-80 ℃.In addi-tion,all 17 amino acids were detected in all 12 drying methods,including 7 essential amino acids and 9 medicinal amino acids.The pro-portion of essential amino acids to total amino acids(EAA/TAA)ranged from 31.80％to 36.51％,with an average of 34.36％and the proportion of medicinal amino acids to total amino acids(MAA/TAA)ranged from 57.72％to 67.84％,with an average proportion of 63.12％.Three principal components were extracted through principal component analysis,and their cumulative variance contribution rate reached 92.83％.The comprehensive score showed that vacuum freezing at-80 ℃ had the highest quality.Cluster analysis divided the 12 drying methods into 3 categories,with vacuum freezing at-80 ℃ and shade-drying having higher content.This method is simple to op-erate,has good separation effect,and is suitable for simultaneously determining the content of 17 amino acid components in Lycopus lucid-us Turcz.var.hirtus Regel.Among the 12 drying methods,vacuum freezing at-80 ℃ had the highest content and high nutritional value,providing a theoretical and practical basis for the processing of Lycopus lucidus Turcz.var.hirtus Regel.
维普
万方数据