Study Of Extraction Process Of GABA In The Stems And Leaves Of Panax Notoginseng

The stems and leaves of Panax Notoginseng was dry stems and leaves in Panax Notoginseng of Araliaceae. Its average annual production was 2.5 million kg. The planting area of Panax Notoginseng was massive amplification before two years, and its output could be up to 800 to 10 million kg. More and more studies focused on Panax Notoginseng, and the focus of our research from the underground part turned to the aboveground part especially the stems and leaves of Panax Notoginseng. The Notoginseng leaf saponins, Flavonoid glycosides and dencichine obtained from the stems and leaves of Panax Notoginseng. The water-soluble components was not in-depth study especially Amino Acids in the stems and leaves of Panax Notoginseng. GABA was one of the important Amino Acids in the stems and leaves of Panax Notoginseng, and it had not been studied. The comprehensive study about GABA and Notoginseng leaf saponins in the stems and leaves of Panax Notoginseng provided reference index of quality control, provided a reliable source for GABA production, improved the comprehensive utilization of resources.The contents of y-aminobutyric acid in the stems and leaves of Panax Notoginseng in different productive area were determined by using high performance liquid chromatography. And Optimization of the extraction process of GABA in the stems and leaves of Panax Notoginseng used orthogonal method. It purified by Amberlite 732, silica gel column chromatography. Activated carbon as raw material is applied to the decoloration process. The comprehensive study about Notoginseng leaf saponins, GABA and Polysaccharide in the stems and leaves of Panax Notoginseng was studied. The contents of this paper included the following:1. The contents of γ-aminobutyric acid in the stems and leaves of Panax Notoginseng in different productive area were determined by using high performance liquid chromatography. HPLC analysis was made on a C18 (5μm,250 mm X 4.6 mm) with acetonitrile and water containing 0.05 mmol·L-1 sodium acetate as mobile phase. The detection wavelength was 254nm. The HPLC method showed good linearity within the range of 0.1～10 mmol·L-1. The average recovery of GABA in the stems and leaves of Panax Notoginseng was 101.7%(RSD= 1.14%, n= 3) respectively. The contents of GABA in the samples of different productive areas were not significant differences, and the average contents of GABA in the stems and leaves of Panax Notoginseng were 0.49%. This method was simple operation, and stable results, and it was suitable for the determination of γ-aminobutyric acid in the stems and leaves of Panax Notoginseng. And these were provide reference index of quality control.2. The optimum conditions for the extraction of GAB A from the stems and leaves of Panax notoginseng were determined. On the basis of single-factor experiments (extraction solvent, time, times, temperature, material ratio), the experiment with criterion of GABA yield was combined with orthogonal experiment. The optimum extraction was based on three times for 3 h at 60℃ with water, and the material ratio was 1:10, and the content of GABA from the stems and leaves of Panax notoginseng was 0.46%, and these will provide the technical support for comprehensive development and utilization of the aerial part of Panax notoginseng.3. In this study, the decoloration process was optimized by the basis of single-factor experiments (decolorization media, decolorization media usage, decolorization time, decolorization temperature). The optimum decoloration condition was based on 2% activated carbon for 30 min at 60℃. Under this decolorization condition, it was the best result and ensured appearance and color of GABA.4. In this part, it purified by Amberlite 732, silica gel column chromatography. The optimum purification process was based on Amberlite 732 for 60 min at 1 mL·min-1 with 10 BV pH 10 elution solution. Under this purification condition, the result was the best. GABA purified by silica gel column chromatography after Amberlite 732. A white crystal was obtained after gradient solvent system of methanol/dichloromethane. Through a variety of physical, chemical and spectroscopic identification, the white crystal was GABA, and the GABA (its content of 20%) yield was 1.72%.5. The comprehensive study about Notoginseng leaf saponins, GABA and Polysaccharide in the stems and leaves of Panax Notoginseng was studied. The Notoginseng leaf saponins (its content of 57%) yield was 7.79%, and the Polysaccharide (its content of 38.1%) yield was 20.1%. Such a comprehensive extraction method improved the comprehensive utilization of the stems and leaves of Panax Notoginseng.