Study on quality components and sleep-promoting effect of GABA Maoyecha tea

Maoyecha tea, a natural non-caffeine and high-theobromine-containing tea variety, is a special tea resource in southern China. The aims of this study were to analyze the changes in quality components of Maoyecha tea during anaerobic treatment, and to investigate whether or not the extract of gamma-aminobutyric acid (GABA) present in Maoyecha tea has the sleep-promoting effect. The results showed that GABA content in Maoyecha tea was increased significantly and reached the standard of GABA tea after anaerobic treatment. The contents of free amino acids and alkaloids were also significantly increased whereas polyphenols and water extract were reduced. At the same time, treatment under vacuum accelerated the transformation of catechins. More importantly, the extract of GABA Maoyecha tea was shown to have the sleep-promoting effect. These neuropharmacological properties are possibly and mainly mediated via the GABAergic neurotransmission.