RP-HPLC法分析萱草属植物花蕾中游离氨基酸组成

Analysis of Free Amino Acids in Flower Buds of Hemerocallis Genus Plants by RP-HPLC

目的:分析萱草属植物8个野生种和25个栽培品种花蕾中游离氨基酸的组成特性。方法:以邻苯二甲醛作为衍生试剂,采用柱前在线衍生反相高效液相色谱法对该属植物花蕾中游离氨基酸组成进行分析,利用主成分分析法对游离氨基酸进行综合评价。结果:供试样品游离氨基酸总量在6.864~21.219 mg/g之间;在萱草属植物花蕾中能检测出14~16种游离氨基酸,且含量存在差异;其中呈味氨基酸以Asp、Gly、Ser和Glu等鲜甜味氨基酸含量最为丰富。通过综合评价指数得出:萱草属植物中食用品种黄花菜、小黄花菜、北黄花菜和‘白花’萱草等的品质最优,‘金娃娃’萱草和‘春节’萱草的品质较优,‘馨口’和‘银光芙蓉’萱草的品质最差。

Objective: To analyze the composition of free amino acids in flower buds of plants from 8 wild species and 25 cultivated species of the genus Hemerocallis. Methods: A high performance liquid chromatography(HPLC) method to determine free amino acids in flower buds of Hemerocallis genus plants was proposed using on-line precolumn derivatization with o-phthalaldehyde. Comprehensive evaluation of these Hemerocallis species based on free amino acid composition was performed by principal component analysis. Results: The results showed that the total amount of free amino acids varied from 6.864 to 21.219 mg/g in flower buds of the 33 Hemerocallis species tested;14–16 kinds of free amino acids were detected and their contents differed among different Hemerocallis species. All the investigated samples were richest in asparagine, glycine, serine and glutamic acid among the flavor amino acids identified. Based on comprehensive evaluation index, the edible species of Hemerocallis, Hemerocallis citrine, Hemerocallis minor, Hemerocallis lilioasphodelus and Hemerocallis bearing white flowers, had the best quality followed by Hemerocallis ‘Stella Deoro' and Hemerocallis ‘First Spring', whereas Hemerocallis ‘Xinkou' and Hemerocallis ‘Yinguangfurong' showed the poorest quality.