Separation,Antioxidation And Inhibiting Non-enzyme Glycation Activities Of Ethanol Extracts From Wheat Germ

Wheat germ, the main by-product obtained from a commercial mill, which is riched in bioactive components, with effects of antioxidant, anticancer and so on, have great development prospects. In this experiment, the extraction and separation conditions of Ethanol extract of Wheat Germ(EWG) were optimized based on flavonoids of wheat germ. And the antioxidant activity, inhibition of non-enzymatic glycation end products AGEs activity in vitro of EWG were studied, details as follows:The effects of extraction conditions were investigated, and the optimum extraction process of EWG was as follows: ethanol concentration of 70%, ratio of solid to liquid of 1: 16(g: m L), extraction time of 2.0 h, extraction temperature of 60 °C. Under these conditions, the extraction of EWG was best, and the yield of flavonoids in crude EWG was reached the highest 0.3679%.Separation of EWG were studied using seven macroporous resins namely AB-8, D101, H103, HPD100, HPD300, HPD500, X-5 and four polyamides. The static tests indicated that H103 resin was appropriate. To optimize the separation process, adsorption and desorption tests were carried out. The optimal adsorption parameters were: sample concentrations of about 0.65 mg / mL, flow rate of 2.0 BV / h. The optimal desorption parameters were 70% ethanol, flow rate of 2.0 BV / h. After one run treatment with H103 resin, the extraction of EWG was increased 12.26 times, and the content of flavonoids in this isolated EWG was up to 11.77% from 0.96%.The antioxidant activities of the EWG were further evaluated in vitro by the experiments of the scavenging radicals, chelating metal ions, reducing power and total antioxidant. The results showed that, the antioxidant activities of EWG, such as scavenging radicals, chelating metal ions, reducing power and total antioxidant capacity were increased with the concentration increasing, The IC50 values of scavenge hydroxyl radicals and metal ion chelating capacity were 0.401?0.803 mg / mL, respectively. At different concentrations(0.4 ~ 1.0 mg/mL), the scavenging superoxide anion capacity was stronger than Vc.To investigate the inhibitory effects of EWG on the protein glycation in vitro, the Bovine Serum Albumin- Glucose(BSA-Glucose), Bovine Serum Albumin- Fructose(BSA-Fructose) and Bovine Serum Albumin- Glyoxal(BSA-Glyoxal) assays were used. The results showed that, the AGEs which in these glycosylation systems could be inhitited by EWG, and the higher the concentration of EWG, the better the effect of inhibiting. The EWG showed stronger inhibitory effects on BSA-Glucose system than aminoguanidine(AG), and weaker on BSA-Fructose, BSA- Glyoxal system than AG.