Extraction And Hypolipidemic Research Of Polyphenol From Millet Bran

With millet bran as raw material,this study investigated the extraction of polyphenols from rice bran and its hypolipidemic effect.First,the methods of conventional solvent,enzymatic,ultrasonic,microwave,ultrasonic and microwave were comparatively studied in order to determine the best technology.Secondly,the microwave extraction process was optimized by response surface method and the optimum technological conditions were obtained.And using the macroporous adsorption resin,we purified the millet bran polyphenols by high performance liquid phase and mass spectrometry.Finally,the hypolipidemic effect of the millet bran was studied by mouse experiment.The conclusion is as follows:1.The best process and the optimum technological conditions for polyphenol extraction from millet bran were determined.The experiment through single factor experiment by the methods of conventional solvent,enzymatic,ultrasonic method,microwave method and Ultrasonic and microwave combined method,respectively.Preliminary determined the best technology of extracting millet bran polyphenols.The optimum technological conditions were optimized by the response surface experiment.The results showed that the best method of millet bran polyphenols yield was microwave assisted extraction,The optimum extraction condition was microwave power 400 w,microwave time to 120 s,the percentage of ethanol 71%,under this technological conditions for millet bran polyphenols extraction was the optimal yield of 137.36 mg/100 g.2.The optimum and purification conditions of millet bran polyphenols were determined.We selected three kinds of macroporous adsorption resin,through static adsorption and desorption experiments compared three kinds of macroporous adsorption resin adsorption separation effect of millet bran polyphenols,and screened the better macroporous adsorption resin by adsorption separation effect.Then the dynamic adsorption performance were studied,and the optimum adsorption conditions were determined.The results showed that AB-8 macroporous adsorption resin for millet bran polyphenols had the best adsorption and desorption effects.Using dynamic adsorption test,the optimum process conditions were determined:the column on the concentration was 0.2 mg/ml,p H was 4,the column on the rate was 2 ml/min,the elution process: the elution rate was 1ml/min,the percentage of eluting liquid was 75%,and the elution volume was 90 ml.3.The extracts of millet bran was preliminarily identified and analyzed by means of HPLC-ESI-MS.The results showed that the material extracted from millet bran were polyphenols.The polyphenols compounds of millet bran were identified by means of high performance liquid chromatography column separation and mass spectrometry analysis.And the polyphenol compounds of millet bran may contain rutin and 4’,7-Dihydroxy-6-methoxy isoflavone.They could reduce total cholesterol and triglycerides,so the preliminary inference that millet bran polyphenols may have certain function for hypolipidemic.4.The study used the model of cholesterol fed rats to evaluate the effect of hypolipidemic activity with millet bran polyphenols.The rats were divided into the normal control group,the high-fat group,the positive control group,and the groups of the low,medium and high-dose group with millet bran polyphenols supplementation were compared and analyzed.The results showed that that cholesterol fed rats for four weeks,compared with normal group,serum TC,TG and LDL-C parameter values of cholesterol fed rats were significantly increased,serum HDL-C was significant decreased,weight increased and food consumption was increased,and the parameter values of liver was also obviously changed,the cholesterol fed rats was established successfully.Supplemented millet bran polyphenols can reduce the weight increment and serum TC,TG,LDL-C parameter values of rats serum were significantly lower,serum HDL-C parameter values increased significantly.The decrease of MDA and the increases of T-SOD,the various parameters in liver tissue was close to normal control group.The results in the present study also showed that the polyphenols from millet bran may be useful for ameliorating hyperlipidemia and clinical significance.