Abstract: The extraction conditions and thin layer chromatography scanning (TLCS) analytic method of γ-aminobutyric acid from pumpkin leaves were studied. On the basis of single factor experiments, orthogonal test was investigated. The optimum parameters for extracting γ-aminobutyric acid from pumpkin leaves were determined as follows: the concentration of alcohol was 20%, the ratio of solid to liquid was 1:17(w/v), and the extraction time was 1 h. Under these conditions, the yield of γ- aminobutyric acid was 209 mg/100 g. The calibration curve showed good linearity in the range of 0.125 to 2.0 mg/mL (r2 =0.9991) with the average recovery (n=4) of 99.61%.

Key words: pumpkin (Cucurbita mosehata) leaves, γ-aminobutyric acid, extraction, determination