Study On The Preparation Technology Of Allyl Isothiocyanates As Foodborne Bacteriostatic Agent

Allyl isothiocyanates with antimicrobial properties,it has widely applied in food antimicrobial antiseptic and soil disinfection.At present,the natural transformation process of allyl isothiocyanates with some problem,such as uncontrolled,high cost,low target conversion.This article obtained a highly efficient transformation of immobilized enzyme preparation methods through the study of preparation on allyl isothiocyanates.The main conclusions are as follows:1.On the basis of single factor experiment,the optimal preparation technology of the allyl isothiocyanates from horseradish has been optimized by response surface design(RSM).The optimum preparation conditions of allyl isothiocyanates by HPLC was:pH at 7.26,liquid ratio at 1:15.82 g/mL,reaction temperature at 48.98℃,reaction time at 1.52 h.In validation tests,the yield of the total isothiocyanates was 0.468%,the yield of allyl isothiocyanates was 0.371%,both consisted with the model prediction results.2.On the basis of single factor experiment,the extraction process of allyl glucosinolates from horseradish has been optimized on the basis of orthogonal test by solvent reflux method and ultrasonic method.Studies have shown that:the yield of ultrasonic assisted extraction from allyl glucosinolates was 1.72 times than solvent reflux extraction.The extraction time has shorted 4.5 times.The optimal process conditions was:the material liquid at 1:20 g/mL,concentration of ethanol at 75%,ultrasonic power at 400 W,extraction temperature at 40℃,extraction time at 40 min,the yield of allyl glucosinolates was 4.342%.3.On the basis of single factor experiment,the extraction process of myrosinase was researched by response surface design(RSM).Research shows that:The optimal extraction conditions was pH at 6.89,extraction temperature at 31.44℃,extraction time at 1.52h,and solid-liquid ratio at 1:15.73g/mL,choose ethanolas for precipitation,the dosage was 60%.Under the best condition,the predictive value of the specific activity on myrosinase was 1.999U/mg,the test value was 1.968U/mg,the error is 1.55%.Dextran gel filtration choose the best elution buffer was 0.05 M pH 9.1 Tris-Hcl+0.15 M NaCl.Under the condition,the purity of the elution protein peak was high.4.The immobilization technology of myrosinase was researched by single factor experiment,selected the silicone amino magnetic microspheresand and polysaccharide amino magnetic microspheres as immobilized carrier.Studies have shown that:the most appropriate immobilized carrier was silicone amino magnetic microspheresand.The optimal immobilized conditions was:the amount of enzyme at 0.12 mg/mL,activation time at 1 h,crosslinking time at 3 h,the vibration frequency at 140 times per min,under the condition of the stability of the immobilized enzyme is good.The immobilized enzymatic conversion rate of allyl isothiocyanates was 33%.