Studies On The Component Type And Hypocholesterolaemia Effect Of The Effective Constituent Groups In The Fistular Onion Stalk

Fistular onion stalk is the fresh bulb of Allium fistulosum L. var. caespitosum Makino., belonging to the Liliaceae family. Almost Allium species are the source of potential medical agents, useful for the prevention or treatment of many diseases, including cancer, cardiovascular disease, antibacterial, and so on. Many of these biological effects are related to the volatile sulfur compounds, steroids, saponins, volatile oils, nitrogen compounds, polysaccharide and flavonoids[1-2]. Sulfur compounds, steroidal, unsaturated fatty acids compounds, and flavonoids were confirmation as the effective ingredient of the Fistular onion stalk supercritical CO₂ extract (the crude drug of BoXinTong) in the preliminary studies. Therefor this research mainly focuses on the enrichment and pharmacodynamics of effective composition in the extract of Fistular onion stalk, and expand study to the polarity composition from the Fistular onion stalk.Molecular distillation which is suitable for enriching and separating the heat-sensitive compounds was used when enrich the volatile organic compounds in the Fistular onion stalk supercritical CO₂ extract, and GC-MS was adopted to analysis the fractions. In the appearance, some fractions is yellowish oil, while others are dark green solid, which is different from oily semi-solid belonging to the extract. The GC-MS result also show that this technology can enrich some compounds, especially fatty acid ingredients and pathalic acid ester composition, but did not reach the expected results in the part of the enrichment of sulfur compounds.Using the classical urea complexation method to enrich the unsaturated fatty acid in the Fistular onion stalk, the GC result show that the content and kinds of saturated fatty acid in the enrichment product reduced obviously, while the content of unsaturated fatty acid increased significantly, which can achieve 80%.The another major component in Fistular onion stalk is the steroidal compound, which was enriched by using the method of solvent recrystallizate. Removing of the fatty acid composition by saponification was the first step, and then applies pyruvate to carry out step-by-step recrystallizate to get enrichment product fainally that was the buff solid. The content of the steroidal can achieve 50% in this product by using UV to analysis.The polar fractions in the Fistular onion stalk have also been studied. Fistular onion stalk was dried by microwave drying, and then adopted the method of solvent heating reflux extraction and organic solvent extraction followed to obtain the n-butanol parts, the content of saponins in which part is not lower than 20%.In pharmacology, the hyperlipdemia model was made by using the classical method of feeding the experimental animals with fat-rich diet, and the results show the model was copied successfully. Liver index, the concentration of the TC and TG, LDL-c, HDL-c, in the serum, liver function index of GPT and GOT, antioxidant damage index of MDA and SOD, proinflammatory factor of CRP and IL-6 were tested to study the hypocholesterolaemia effect and investigate the mechanism of each drug preliminarily. The result showed that the treatment group of n-butanol parts and Fistular onion stalk extract have obvious curative effects in the part of lowering blood lipid level of TC, LDL-c as well as increasing LDH-c level compared with the model group(P<0.01), and in this respect the effect of Unsaturated fatty acid group and steroidal compounds group were also obvious compared with the model group(P<0.05). Unsaturated fatty acid group showed the best effect in the indicators associated with liver function and n-butanol parts group showed the strongest capability about antioxidant injury, while the Fistular onion stalk extract group was secondly. Unsaturated fatty acid group can reduce inflammation response obviously compared with model group when statistical the concentration of serum CRP(P<0.01) and IL-6(P<0.05).The feature about this paper is that the method of molecular distillation introduced to enrich the compounds in the Fistular onion stalk supercritical CO₂ extract for the first time, and the results also show that this method is effective in enrichment especially to the unsaturated fatty acids. In this study, the different types of compounds in the Fistular onion stalk supercritical CO₂ extract were enriched respectively for the first time, and then the pharmacodynamic study of this compounds provided the more clearly basis to determinate Pharmacodynamic composition in the Fistular onion stalk supercritical CO₂ extract. Finally, the hypolipidemic effect of the butanol extract that is the polar fractions in the Fistular onion stalk was also studied, which provides the support for the comprehensve reseach and applications of the Fistular onion stalk.