不同采收期枇杷叶中氨基酸的组成与分析

Composition and Analysis of Amino Acids in Eriobotryae folium at Different Harvesting Stages

目的 对12个月份采收期枇杷叶的氨基酸成分组成及含量变化进行分析,为确定枇杷叶采收期及资源利用提供理论依据。方法 采用异硫氰酸苯酯柱前衍生化高效液相色谱法测定不同月份枇杷叶氨基酸组成及含量;采用SPSS22.0版软件进行数据统计学差异及相关性分析;根据世界卫生组织(WHO)和联合国粮农组织(FAO)提出的理想模式及朱圣陶提出的氨基酸比值系数法,对不同采收期的枇杷叶氨基酸进行评分。结果 不同采收期枇杷叶中均含有17种氨基酸,7种人体必需氨基酸(EAA)、9种儿童必需氨基酸(CEAA)及9种药用氨基酸。17种氨基酸分别是天门冬氨酸、谷氨酸、丝氨酸、甘氨酸、组氨酸、精氨酸、苏氨酸、丙氨酸、脯氨酸、酪氨酸、缬氨酸、甲硫氨酸、胱氨酸、异亮氨酸、亮氨酸、苯丙氨酸、赖氨酸,它们的平均含量分别为3.41~7.23、4.64~9.66、2.05~3.75、2.99~4.95、0.01~1.56、2.33~4.85、2.10~4.03、2.67~5.48、5.37~7.64、1.45~3.49、2.70~5.53、0.01~0.48、3.64~4.78、1.91~4.15、3.96~7.83、2.39~4.60、1.85~3.65 mg·g^(-1)。不同采收期枇杷叶中17种氨基酸、总氨基酸(TFAA)、EAA总量、CEAA总量、药用氨基酸、苦味氨基酸的含量间差异有统计学意义(P<0.05);苦味氨基酸在总氨基酸中的百分含量较稳定。不同采收期枇杷叶的EAA含量为44.26%~50.33%,明显高于WHO/FAO模式值(35.00%);EAA/非必需氨基酸(NEAA)均值(55.67%)和EAA/TFAA均值(35.74%)分别接近WHO/FAO模式值的60%、40%;不同采收期枇杷叶的17种氨基酸含量峰值前2位是7月和11月;氨基酸比值系数分(SRC)值为62.53~76.17,前3位为11月、8月及7月。赖氨酸为枇杷叶的第一限制氨基酸。苦味氨基酸与药用氨基酸、TFAA呈正相关(P<0.01)。结论 枇杷叶中氨基酸种类齐全,组成合理,具有较佳开发利用价值;不同月份氨基酸的含量差异大,7月和11月是枇杷叶氨基酸合理开发利用的较佳时期。

Objective To analyze the changes in the amino acid composition and content of Eriobotryae folium in the twelve months,and to can provide a theoretical basis for the harvesting period and resource utilization of Eriobotryae folium.Methods The amino acid composition and content of Eriobotryae folium in different months were determined by high performance liquid chromatography with phenyl isothiocyanate pre-column derivation.SPSS22.0 software was used to analyze the statistical significance difference and data correlation.According to the ideal model proposed by the World Health Organization(WHO)and the Food and Agriculture Organization of the United Nations(FAO)and the amino acid ratio coefficient method proposed by Shengtao Zhu,the amino acids of Eriobotryae folium at different harvest periods were scored.Results There were seventeen kinds of amino acids,including seven essential amino acids(EAA),nine kinds of children's essential amino acids(CEAA),and nine kinds of medicinal amino acids in Eriobotryae folium at different harvesting periods.The seventeen amino acids were aspartic acid,glutamic acid,serine,glycine,histidine,arginine,threonine,alanine,proline,tyrosine,valine,methionine,cystine,isoleucine,leucine,phenylalanine,and lysine;and the average contents were 3.41-7.23,4.64-9.66,2.05-3.75,2.99-4.95,0.01-1.56,2.33-4.85,2.10-4.03,2.67-5.48,5.37-7.64,1.45-3.49,2.70-5.53,0.01-0.48,3.64-4.78,1.91-4.15,3.96-7.83,2.39-4.60,1.85-3.65 mg·g^(-1),respectively.There were significant differences in the contents of seventeen kinds of amino acids,total amino acids,total essential amino acids,total essential amino acids for children,medicinal amino acids,and bitter amino acids in Eriobotryae folium at different harvesting stages(P<0.05).The content of bitter amino acids in total amino acids was stable,and there was no significant difference.The content of essential amino acids was from 44.26%to 50.33%in Eriobotryae folium at different harvesting periods,significantly higher than the WHO/FAO model value(35.00%).The mean values of EAA/NEAA(55.67%)and EAA/TFAA(35.74%)were close to 60%and 40%of the WHO/FAO model values,respectively.The highest content of seventeen kinds of amino acids in Eriobotryae folium was found in July and followed in November.SRC values ranged from 62.53 to 76.17;the highest value was November,the second was August,and the third was July.Lysine was the first limiting amino acid in Eriobotryae folium.Bitter amino acids were positively correlated with medicinal and total amino acids(P<0.01).Conclusions The amino acids in Eriobotryae folium have a complete variety,reasonable composition,and good development and utilization value.The contents of amino acids in different months varied greatly.July and November were the optimal periods for the rational development and utilization of amino acids in Eriobotryae folium.