叶面喷施氨基酸对茶叶中γ-氨基丁酸含量的影响

Influence of Amino Acid Foliar Application on the Amount of γ-Aminobutyric Acid in Tea Leaf

用不同种类、不同浓度氨基酸喷施茶树,采摘鲜叶并进行真空厌氧处理。比较分析不同处理对茶叶中γ-氨基丁酸(GABA)生物合成量、厌氧处理对茶样中各氨基酸含量以及施肥时间对GABA合成的影响。结果表明,茶树喷施氨基酸后,经真空厌氧处理茶鲜叶中γ-氨基丁酸含量明显上升,6种氨基酸对GABA合成的影响作用由高到低为谷氨酸、天冬氨酸、谷氨酰胺、苯丙氨酸、甘氨酸、丙氨酸。茶鲜叶中氨基酸含量尤其是谷氨酸、天冬氨酸及茶氨酸含量高低可以作为评价GABA合成作用的指标;叶面喷施谷氨酸5d时,茶鲜叶中氨基酸总量以及谷氨酸、天冬氨酸和茶氨酸增加总量最高。综合分析确定施0.5%谷氨酸叶面肥5d后,采摘一芽二、三叶鲜叶,常温下厌氧处理8h,是生产γ-氨基丁酸茶的理想方法。

Vacuum and anaerobic treated fresh tea leaves which sprayed by different kind or concentration of amino acid were investigation. The influence on the γ-aminobutyric acid （GABA） biosynthesis by different treatments were analyzed. The result showed that the content of γ-aminobutyric acid was enhanced obviously after foliage-sprayed and vacuum treatment. The influence of six types of amino acid on the ability of γ-aminobutyric acid biosynthesis was Glutamic Acid 〉 Asparticacid 〉 Glutamine 〉 Phenylalanine 〉 Glycine 〉 Alanine. The content of Glutamic acid, Aspartic acid and Thenine in tea fresh leaves may be the criterion of synthesizing ability for γ-aminobutyric acid. The total content of Glutamic acid, Aspartic acid and theanine has reached the peak on the fifth day in tea fresh leaves. 0.5% Glutamic acid sprayed on tea leaves for 5 days is the best method.