6种石斛属植物氨基酸组成及营养价值评价

为比较不同种石斛的氨基酸组成差异,作出营养评价,使用氨基酸自动分析仪检测6种石斛的氨基酸含量,分析其必需氨基酸组成成分,并通过计算氨基酸评分(AAS)、化学评分(CS)及氨基酸比值系数分(SRCAA)等非生物指标进行营养评价。结果表明:石斛中氨基酸种类齐全、营养丰富,均含有被检测的17种氨基酸。6种石斛氨基酸总量存在差异,介于3.58%～8.09%。必需氨基酸组成总含量介于42.62%～47.23%之间,明显高于WHO/FAO模式值(35.00%),其中,化学评分显示其限制氨基酸均为半胱氨酸和蛋氨酸。6种石斛药用氨基酸含量相差较大(2.24%～5.37%),其中蜻蜓石斛含量最高,为含量最低细叶石斛的2.40倍,但在总氨基酸中所占的比例基本一致(60.96%～66.47%)。对6种石斛进行聚类分析可分为4类,其中杓唇石斛、叠鞘石斛、细叶石斛可视为高品质蛋白质种。综上所述,石斛氨基酸具有重要的营养价值,6种石斛氨基酸差异显著。该结果可为石斛营养价值评价、品种选育及药用开发提供理论指导。

Amino acid composition and nutritional value evaluation of 6 species of Dendrobium

To compare the amino acid composition of different Dendrobium ,make nutritional assessment.Amino acid content of 6 different germplasm Dendrobium was determined by automatic amino acid analyzer,analyzing the components of essential amino acids.Nutrition evaluation was conducted by calculating non-biological indicators such as amino acid score (AAS),chemical score (CS) and amino acid ratio coefficient score (SRCAA).Results indicate that the variety of amino acids in Dendrobium is complete and nutritious,all Dendrobium contained 17 amino acids tested.The total amino acid content of Dendrobium varied from 3.58% to 8.09%.The total content of essential amino acids was between 42.62% and 47.23%,which was significantly higher than the WHO/FAO model value (35.00%).The chemical score indicated that the limited amino acids were cysteine and methionine.The amino acid content of different Dendrobium varied greatly (2.24%-5.37%),among them the content of SH4 was 2.40 times as high as that of SH3,however,the proportion of total amino acids is basically the same (60.96%-66.47%).The cluster analysis of 6 Dendrobium can be divided into 4 categories, D.moschatum , D.denneanum , D.hancockii can be regarded as high quality protein germplasm.To sum up,the amino acid of Dendrobium has important nutritional value,and the amino acid of different germplasm Dendrobium has significant differences.This result can provide theoretical guidance for the nutritional value,variety breeding and medicinal development of Dendrobium .