微波辅助酶法制备米糠蛋白工艺对黄曲霉毒素B_1脱除及酶解效果的影响

以受黄曲霉毒素B_1(aflatoxin B_1,AFB_1)污染的米糠为原料,研究微波辅助酶法对米糠中AFB_1脱除效果的影响。初始米糠中AFB_1浓度为102.54μg/kg,以料液比(g∶m L)1∶10、加酶量0.50%、α-淀粉酶和纤维素酶酶解液pH6.0、温度50℃、处理时间2 h的工艺条件制备米糠蛋白。结果表明,米糠中AFB_1残留浓度为56.03μg/kg(脱除率为45.36%),米糠中蛋白质回收率为78.20%;基于该工艺研究,在单位体积微波功率750 W和处理时间10 min的条件下,由酶法提取的米糠蛋白制品中AFB_1残留浓度为4.21μg/kg(脱除率为92.48%),符合国家标准(≤10μg/kg),而蛋白质回收率达到81.36%。本研究采用免疫亲和柱净化结合HPLC-FLD检测法,提高AFB_1的检出限至0.10μg/kg。微波处理不仅对米糠蛋白中AFB_1有明显的脱除效果,且有利于蛋白回收率的提高。该法操作简单,脱除效率高,可应用于受黄曲霉毒素污染的米糠制品中。

Effect of Microwave-assisted Enzyme Treatment on Aflatoxin B1 Removal and Enzymatic Hydrolysis During the Preparation of Rice Bran Protein

In this study,the efficiency through the microwave-assisted enzyme treatment degradation of AFB1 in rice bran-protein was explored.Initial concentration of AFB1 was 102.54 μg/kg,and the conditions of the enzyme treatment were solid-liquid ratio (g:mL) 1:10,enzyme dosage 0.50％ of α-amylase and cellulase,pH 6.0,temperature 50 ℃ and treatment time 2 h.The results showed that the concentration of AFB1 decreased 45.36％ during the preparation of rice-bran protein by the enzyme treatment,and the residual concentration of AFB1 was 56.03 μg/kg,and the recovery rate of protein was 78.20％.Based on the enzyme treatment,after the treatment of microwave power per unit volume 750 W for 7 min,the degradation rate of AFB1 was 92.48％,and the residual amount of AFB1 was 4.21 μg/kg,which meets the requirement of national standard (≤ 10 μg/kg),and the recovery rate of protein was 81.36％.Immunoaffinity column clean-high performance liquid chromatography-fluorescence detection method could improve the detection limit of AFB1 to O.10 μg/kg.Microwave-assisted enzyme treatment contributed to the degradation of AFB1 in rice bran-protein and was beneficial to the recovery rate of protein.This method was simple and efficient,and it could be applied to the crops contaminated with aflatoxin.