The Study Of Using Rice Residues To Produce ACE Peptide

Rice residue is the byproduct after monosodium glutamate factory, glucose factory, winery, maltodextrin plant utilized the starch in the rice. The main component of rice residue are protein and carbonhydrate, the protein contents in rice residue are very higher than rice and bean. It’s a hudge waste that rice residue has not been well developed while it’s a good protein resource. This paper mainly investigates the extraction of rice residue protein, optimum process about enzymic method of preparing ACE inhibitory peptides, seperation and purification of ACE inhibitory peptides and the ACE inhiitoy activity. Main results are as follows:Protein extraction rate was taken as index to optimized alkali extraction conditions. The best technology of protein extraction comes out from the orthogonal test on the basis of sole element test:partical size is80mesh, solid-liquid ratio is1:10, pH is12,temperature is40℃and time is4hours. Under this condition, the protein contraction of rice residue can reach68.2%and the purification can reach80.5%.Degree of hydrolysis was taken as index to optimized enzymatic hydrolyze protein extracted from rice residue. Choose alkaline protease from all four kinds of protease as the optimal enzyme..The optimum process of hydrolysis comes out from the orthogonal test on the basis of sole element test:the alkaline protease volume has to be6000U/g, the time has to be5hours, the pH needs to be9.0and the temperature has to be60℃.Ultrafiltration enzymatic hdrolyzate of protein extracted from rice residue by ultrafiltration. It’s found that the component of lower moleculer weight has larger ACE inhibitory activity, component whose moleculer weight less than3kDa has the ACE inhibitory activity reached86.50%, it also prove that small peptides play a major role in ACE inhibitory activity. Select the Sephadex G-15gel column separate and purify the component less than3kDa get6peaks, of which the component named F has the ACE inhibitory activity reached91.64%.Simulated digestion test shows that the ACE inhibitory activity of component F resist the digestive system very well, so it can be used for the preparation of the antihypertensive peptides.