Research Of Legumes Seeds Trypsin Inhibitors Inactivated By Enzyme

As one of protein resource or people in new century, the legume seeds are very important, But the use of legume is influenced by antinutritions of legume all the time. This thesis includes the researches on peanut trypsin inhibitor(PTI) and soybean trypsin inhibitor(STT) hydrolyzed by subtilisin, STI inactivated by the enzyme existing in mung bean and soybean burgeon. A new way about the use of legume seeds protein was provided by the results of researches. The main work and results are as follows:1 Trypsin inhibitors hydrolyzed by subtilisinBeing proved by the modified N_α-Benzoyl-DL-Arginine-P-Nitroanilide(BAPNA) method and SDS-PAGE, PTI could be hydrolyzed by subtilisin at 40⁶0°C, pH7.0⁸.0, enzyme activity≥40000IU/mL and reaction time≥60min, while STI was at 35⁵5°C, pH7.5⁸.5, enzyme activity≥40000IU/mL and reaction time≥40min by using mono-factor research and modified random-centroid optimization(MRCO) program.2 Enzymatic properties of free and immobilized subtilisinThe researches include the modified PTI and degrease soybean powder(DSP) hydrolyzed by subtilisin respectively, determining the kinetics constant of reactions which PTI and STI were hydrolyzed by subtilisin, and immobilizing of subtilisin with sodium alginate. It was found that modified PTI became sensitized to subtilisin, and the STI of DSP can be hydrolyzed by subtilisin. The K_m, and V_max value of subtilisin for PTI and STI were 657.9BAEE/mL and 606.1BAEE/mL, 104.9BAEE/(min·mL) and 106.6BAEE/(min·mL) respectively. The optimization reaction conditions of STI hydrolyzed by immobilized subtilisin was at 40⁶0 °C, pH7.0⁹.0 and reaction time≥60min. The apparent K_m* and V_max* value of immobilized subtilisin for STI were 825.7BAEE/mL and 85.47BAEE/(min ? mL). The half life of immobilized subtilisin was about 3.1 days.3 STI inactivated by enzyme existing in mung bean and soybean burgeonSTI can be inactivated by the enzyme from mung bean and soybean burgeon proved by the modified BAPNA method and SDS-PAGE. The suitable germinating time of mung bean was 18²0h and soybean was 42⁴6h. The optimized pH value of buffer for the extraction of enzyme from mung bean and soybean burgeon was 7.5⁸.5.