The Content Measurement Of Gelsemium Crude Extracts And In Vitro Metabolism Of Major Gelsemium Alkaloids

The Gelsemium elegant Benth is also known as Duan Chang Cao, which is distributed in North America and southeaster Asia. A number of studies showed that Gelsemium possess variety of pharmacologal properties, including anti-tumor, growth, insecticidal itching, immune function. However, Gelsemium is a known toxic plant, and its toxicity limits its appropriate dosage and clinical use. As the main active and toxicity ingredient of Gelsemium, the content determination and pharmacological effect of Gelsemium alkaloid has been reported, but there were few report of its metabolism. Thus, the content determination of purified Gelsemium alkaloids and metabolism of major alkaloids were investigated. The results can be provided reliable experimental basis for development and metabolism of Gelsemium alkaloids.1 Content determination of Gelsemium alkaloids, sugar, proteins from different extracts of industrializationGelsemium elegant Benth was extracted with three different solvents (95% alcohol, 0.5% H2SO4, water). The results show that the yield of alcohol crude extract, acid crude extract, water crude extract are 6.3%,19.5%,11.2%, respectively. Then, the content of Gelsemium alkaloids, polysaccharides, proteins were determined by using technology of acid dye colorimetric, phenol-sulfuric acid method, coomassie brilliant blue method, respectively. The results showed that the content of alkaloids from three different solvents of 95% alcohol, 0.5% H2SO4, water were 6.44%,2.15%,0.57%; sugar content were 26.41%,8.96%,0.93%; protein contents were 4.47%,1.27%,3.46%, respectively. From the above results, the extraction efficient of alcohol method was higher than that of other methods.2 Purification of Gelsemium alkaloidsThe content determination of the total alkaloids in Gelsemium is more than 80% by acid dye colorimetric method after organic solvent extraction. The quality control of alkaloid extract from Gelsemium elegans was carried out through TLC and HPLC methods with koumine and gelsemine as index ingredients. The results indicated that the experimental samples and reference substances in TLC showed the identical spots with same color and shape at the same position. Koumine and gelsemine accounted for 14.86%,23.28%, respectively, their recoveries were 99.94%(RSD=5.34)and 95.25%(RSD=4.58%), which is provided a quality standards control for Gelsemium alkaloids.3 In vitro motabolism study of koumine, gelsemine in rate and pig liver S9To elucidate the metabolic pathways and metabolic differences among different species for koumine and gelsemine, the metabolite of kounmine and gelsemine in rat and pig liver S9 were characterized using LC-QTOF-MS. The results show that the mainly metabolic pathways of kounmine are oxidation, reduction, dehydrogenation, demethylation in vitro. A total of nine and six metabolites in rat and pig liver S9 was found and identified, respectively. The mainly metabolic pathways of gelsemine are oxidation, demethylation. Four and two metabolites of gelsemine in rat and pig liver S9 were detected and characterized, respectively. The metabolism studies for Gelsemium alkaloids provide an important reference for the metabolic in vivo.