Preparation And Purification Of Corn Oligopeptide And Physiological Function Study

Corn gluten meal(CGM) is a by-product in the process of wet production of corn starch.CGM contain 60% protein, it is mainly used in feed due to its poor taste, so its practical value is not high. CGM can be prepared for the high Fischer ratio oligopeptide by enzymatic hydrolysis. And high Fischer ratio oligopeptide has many biological activities, such as antifatigue, hangover, the function of hepatic encephalopathy treatment.Response surface methodology based on Box-Benhnken experimental design was employed to optimize conditions for the Amylase hydrolysis of corn gluten meal to obtain the maximum degree of removing starch. The optimal hydrolysis conditions were found as follows: pH 6.00, hydrolysis temperature 65.00 ℃, substrate concentration 100 g/L, total enzyme dose 110 U/g, and hydrolysis time 60 min. Under these conditions, the actual content of Carbohydrate reduced 157.333 mg/g, and the predicted value was 154.503 mg/g.Use the multi-enzyme hydrolysis CGM, combinations of three out of three hydrolysis enzymes(protex6L, protex7 L and papain) were used to hydrolyze pretreated CGM.Researched oligopeptide mixture. Using automatic amino acid analyzer, analysis each amino acid content of the prepared oligopeptide mixture, calculate Fischer ratio 28.40.The experimental determined the effects on high Fischer ratio oligopeptide mixture in wheat growth. Obtain that when the high Fischer ratio oligopeptide mixture concentration was10 μg/mL, it was most suitable for wheat growth. In this time SOD activity in wheat leaves were higher 9.43% than the control group; POD activity was higher 24.00% than the control group; CAT activity was higher 39.13% than the control group. The content of solubleCarbohydrates were higher 83.32% than the control group. Chlorophyll a content was higher118.52% than the control group. The total chlorophyll content wrere higher 52.63%. The fresh weight of wheat plant was heavier 40.00% than the control group. Saturated fresh weight was heavier 28.03%. Dry weight was heavier 23.81%. Relative water content was higher 10.65%.The result descripted that high Fischer ratio oligopeptide mixture contributed to the growth of wheat to some extent.High Fischer ratio oligopeptide was separated by sephadex G-25, sephadexG-15 and CM sepharose FF, and select the best separation method sephadex G-15 gel filtration from the three. By adjusting the specifications of the column, the elution flow rate, sample concentration, and the sample volume, the final result that the high Fischer ratio oligopeptide mixture was separated into three components P1, P2, P3. Measured the molecular weight of the three components were 2392 u、1516 u、265 u around.Compare the function of the three isolated components and the high Fischer ratio oligopeptide mixture found there were no significant difference between P3 component and high Fischer ratio oligopeptide mixture in the anti-fatigue and curative effect of treating acute alcoholism. The P3 components obtained were separated by reversed-phase high performance liquid chromatography(RP-HPLC). The samples were dissolved in ultrapure water,12000r/min centrifugal 10 min, retain the supernatant. System: HPLC-U 3000; column:Zorbax SB-C18(4.6 x250μm); injection volume: 10 μL; equilibration buffer: 5% acetonitrile;elution buffer: 5% acetonitrile containing; flow rate: 0.6 mL/min; detection: 220 nm. The composition of P3 component was determinated by mass spectrometry. To achieve two components were A and B. And the mass spectrometry of A and B is glycine-valine-leucine(isoleucine) and methionine-leucine(isoleucine acid).The paper provided an experimental basis on the preparation of high Fischer ratio using CGM and separation and purification, and the function of the anti-fatigue, curative effect of treating acute alcoholism, protecting the liveras well as wheat growth.