Research On Extraction Synchronously Of Protein And Phytic Acid In The Defatted Rice Bran

As the grain agricultural by-product, the rice bran is rich on nutritional component.Many literatures about extraction of the protein or phytic acid from the defatted rice bran had been reported.In this study, the extraction of protein and phytic acid synchronously from the defatted rice bran as the innovation,compared with the former extraction step by step, simplified the extraction process,saved the partial process equipment.The experiment had mainly studied process condition about the extraction of protein and phytic acid synchronously from the defatted rice bran, purification protein conditions optimized by ammonium sulfate precipitation method, the best conditions of ion-exchange purification process of phytic acid by static and dynamic method respectively.The antioxidant activities of phytic acid were also studied.The main conclusions of the experiments were as follows:1. Defatted rice bran was taken as material, by ultrasound-assist, Using pectinase,cellulase,papain to extract rice bran protein and phytic acid synchronously were studied.The experiment results show that:In weakly acidic solution, the extractable amounts of phytic acid was higher by using the way of combination of the cellulose and pectinase after the ultrasound than that in acid method, the extraction of protein was better in ultrasound-assisted enzyme method than that in alkaline method. The optimum conditions were ultrasonic time was 30min, ratio of material to water was 1:10, the extractable protein amounts from 20g defatted rice bran was 1.8043g, the extractable phytic acid amounts was 1.4305g.2.The isoelectric method, ethanol solvent method and ammonium sulfate precipitation method were compared with each other to precipitate rice bran protein, ammonium sulfate precipitation method was better。On the basis of a single factor, precipitating rice bran protein by ammonium sulfate precipitation method was studied by orthogonal test, the best conditions were that mmonium sulfate amounts were 14g, pH was 4.5, salting time was 80min, temperature was room temperature, sedimentation rate of the rice bran protein was 90.36%.3. The 717#, D315, HZD-9 ion exchange resin were compared with each other by static adsorption experiment.The adsorption rate as the target rate of resin were to get the better resin,HZD-9 resin was better than the others.By static absorption-desoption experiment, the optimum condition of HZD-9:absorption time was 2h at room temperature,pH of adsorpting phytic acid was 1～3,the absorption rate of HZD-9 resin was 86.4%, desorption agent was 1.0mol/L NaOH,desorption rate of HZD-9 resin was 83.3%.Under the dynamic experiment, the optimum condition of HZD-9:the velocity of the flow was 2ml/min, the ratio of column diameter to height was 11.5,the penetrated volume was 110ml,the penetrated content was 39.7mg/g. The product can make the mixture of ferric chloride-sulfosalicylic acid fade, and the product was phytic acid via HPL qualitative.The infrared spectra of the refined phytate in structure was the same as standards.4. The hydroxyl free radical was detected by spectrophotometry,and cavenging hydroxyl radicals by phytic acid was studied.By the Fenton reaction, crystallization purple as the capature agent of the hydroxyl free radical,ΔA was measured photometrically and the amount of·OH produced could be determined indirectly.The determination condition was studied and an optimum condition had been obtained.Results:the change in absorbance,ΔA580,was related quantitatively with the amount of crystallization purple and the reactants H2O2 and FeSO4.And phytic acid had an obvious scavenging effect on·OH,the clear rate of phytic acid was 96.0%.