Microwave Extraction Process Of The Active Ingredients In Ginkgo Leaves

The flavonoids and terpene lactones, the main bioactive compounds in ginkgo leaves which is one of the special trees in our country, are used to treat cardiogenic and cerebral disease and senile dementia However, it is lower in the content and the extraction efficiency of flavonoids and terpene lactones by traditional extraction process. To ensure the ginkgo tree to be made the best use of and create the maximal social and economic benefit, it is the problem resolved urgently for improving and developing the process of extracting from Ginkgo Biloba L.Recently, microwave has been increasingly applied to the industry. It had become the most favorable method to extract the nature products because of its more efficiency and less solvents. This paper firstly proposes the microwave-assisted extraction from Ginkgo Biloba L, witch can increase the efficiency and the recovery because of its ability to rapidly and selectively heat the samples.Firstly, ginkgo biloba flavonoids were extracted by water as the solvent from leaves of Ginkgo Biloba L. with microwave treatment. The key factors, including the microwave power, the period of microwave treatment, the volume of water and the period of extraction, were studied. The optimal conditions were identified as the follows,the power of microwave as medium(about 400W);the period of microwave treatment as 60 minutes ;the ratio of liquid to solid as 30:l;the extraction period for 1.0 hour and the temperature as 70C. The extraction rate can be gotten 75% and is 40% higher than it of traditional method. Moreover, the time of extraction is half as much as it.Secondly, we can get the powder containing the ginkgolide by means of initially research on the process of separating Ginkgo flavonoid and ginkgolide. The key factors, including the solvent, the period of extraction, pH, salt ion etal, were stuided The result shows that terpene lactones can be enriched using ethyl acetate as the solvent by adding salts and adjusting pH 8-9 in solution. The problems of emulsion and low extraction rate were resolved by using new extractor.Last, The best adsorbing conditions were determined after the purification of flavonoids by NKA-9 resin had been studied Among this, the pH value of absorbed solution is 6-7; the velocity of adsorbed solution is 3ml/min; the solution is absorbed by resin twice or thrice if it was desorbed by 70% alcohol. The results have shown that the NKA-9 resin is a suitable absorbent for the flavonoid...