The Study On Extraction And Physiological Activities Of Bioactive Substances From Anoectochilus Roxburghii

In this paper, the extraction and physiological activity of active compound from Anoectochilus roxburghii were studied.(1) The extraction of flavonoids from the Anoectochilus roxburghii was studied in this paper. Five levels of the factors (the ratio of water to marterial, ethanol concentration and time) were selected for the spherical symmetric design-response surface methodology to establish a quadric regression equation for describing the yield of flavonoids. By regression analysis, the optimum extraction conditions were obtained as follows: the ratio of water to marterial of 24, ethanol concentration of 63% and time of 48 h, under which the production of favponoids in 1mg Anoectochilus roxburghii (PF) reached with estimated value and verified value being of 10.07mg and 12.63%, respectively.(2) The extraction of polysaccharides from the residue of Anoectochilus roxburghii after extraction of flavonoids was studied in this paper. According to the single-factor experiments, three levels of the factors (extraction temperature, time and the ratio of water to pueraria residue) selected for the Box–Behnken factorial design to establish a quadric regression equation for describing the yield of polysaccharides. By response surface analysis, the optimum extraction conditions were obtained as follows: extraction temperature of 83℃, time of 2.2 h and water-pueraria residue ratio of 35:1, under which the highest yield of polysaccharides reached with estimated value and verified value being of 3.41% and 3.47%, respectively.(3) Polysaccharides was extracted from the Anoectochilus roxburghii with water, NaOH aqua and formic acid(88%). Polysaccharides were isolated and purified by Sephadex G-200 and DEAE-52 chromatography, then the structure characteristics of polysaccharide were analysed with FTIR.(4) We investigated the protective effects of phenolics and polysaccharides isolated from Anoectochilus roxburghii on antioxidant activities in liver injury of CCl4-treated mice. Compared with normal mice, the administration of phenolics and polysaccharides isolated from Anoectochilus roxburghii caused a significant decrease(p<0.05) in glutamate oxalate transa- minase(GPT) and glutamate pyruvate transaminase (GOT). In addition, the phenolics and polysaccharides isolated from Anoectochilus roxburghii caused a significant decrease(p<0.05) in the level of malondialdehyde (MDA) and a significant increase (p<0.05) in the activities of enzymic antioxidants and the levels of non-enzymic antioxidants in liver of CCl4-treated mice. Furthermore, the effect of polysaccharides from Anoectochilus roxburghii was more potent than that of phenolics from Anoectochilus roxburghii at the same dose. (5) The hypoglycemic and antioxidant effects of the water extract from Anoectochilus roxburghii in alloxan-induced diabetic mice were examined. Compared with untreated diabetic mice, the administration of the water extract from Anoectochilus roxburghii for 14 days caused a significant decrease (p <0 .05) in blood glucose levels. Simultaneously, the alteration in lipid metabolism was partially attenuated as evidenced by decreased serum total cholesterol (TC), and triglyceride (TG) levels and by increased high-density lipoprotein cholesterol (HDL) concentration in diabetic mice (p <0 .05). In addition, the water extract from Anoectochilus roxburghii caused a significant increase (p <0 .05) in the activities of enzymic antioxidants and the levels of vitamin E in liver and kidney of diabetic mice, and the tissue(kindey, liver, lung and heart of mice were stained with hematoxylin/eosin, the results showed the tissues were repaired. As a result, it was concluded that the administration of the water extract from Anoectochilus roxburghii could possess the hypoglycemic and antioxidant properties in alloxan-induced diabetics mice.