脱氧剂厌氧处理对茶鲜叶γ-氨基丁酸富集的影响

Effect of Deoxidizer Anaerobic Treatment on the Gama Aminobutyric Acid Enrichment of Fresh Tea Leaf

采用脱氧剂对茶鲜叶进行厌氧处理,分析脱氧剂处理中气体成分、GABA代谢相关酶活力和氨基酸含量的变化,研究脱氧剂厌氧处理对茶鲜叶GABA富集的影响。试验结果表明,脱氧剂厌氧处理中茶鲜叶维持在低氧、高二氧化碳的气体环境中,GABA含量3 h时达到最高值1.22 mg/g,显著高于真空处理的1.05 mg/g(P<0.05);茶鲜叶经过脱氧剂厌氧/好氧处理后,GABA合成酶谷氨酸脱羧酶(GAD)、二胺氧化酶(DAO)和多胺氧化酶(PAO)被激活,分解酶GABA转氨酶(GABA-T)被抑制,其中GAD活力显著高于真空厌氧/好氧处理(P<0.05),其它酶与真空厌氧/好氧处理无显著差异(P>0.05),GABA含量最高达到1.75 mg/g,高于真空处理的1.51mg/g。可见,脱氧剂厌氧对GABA的富集能力优于真空处理。

The effect of deoxidizer anaerobic treatment on the gama aminobutyric acid（GABA） content were studied by removing oxygen with deoxidizer in windtight bags of fresh tea leaves. the changes of gas compositions in windtight bags, the enzyme activities and amino acid contents involved in GABA metabolism were researched. The results showed the low-oxygen, high-carbon dioxide environment was formed and the GABA content of fresh tea leaf was peaked about1.22 mg/g at 3 h in the deoxidizer anaerobic treatment, which was significantly higher than 1.05 mg/g for the vacuum anaerobic treatment（P 〈0.05）. The activities of the glutamic acid decarboxylase（GAD）, diamine oxidase（DAO） and polyamine oxidase（PAO） increased, and the aminobutyric acid-transaminase（GABA-T） decreased under the conditions of deoxidizer anaerobic and aerobic treatment, of them, only the GAD activity was significantly higher than that of vacuum anaerobic and aerobic treatment（P〈0.05） and other enzyme activities had no significant difference compared with the vacuum anaerobic and aerobic treatment（P 〉0.05）. A GABA content of 1.75 mg/g was obtained at 9 h for deoxidizer anaerobic and aerobic treatment, which was higher than 1.51 mg/g for vacuum anaerobic and aerobic treatment. It was found that the effect of deoxidizer treatment on GABA enrichment of fresh tea leaf was superior than the vacuum treatment.