微波、紫外线与臭氧组合技术对霉菌及其毒素的协同影响

Synergistic effects of microwave,ultraviolet and ozone combination on mold spores and aflatoxin

【目的】研究微波(MW)、紫外线(UV)与臭氧(O_3)技术及其组合对玉米霉菌及黄曲霉毒素的影响,为霉变玉米的杀菌和脱毒提供新途径。【方法】在单一试验的基础上,将微波辐照、紫外线照射和臭氧熏蒸进行不同串联(-,各个方式按照试验处理依次进行)和并联(/,各个方式同时进行)组合,应用组合技术对接种平板和染菌玉米表面的霉菌孢子灭活,对染毒玉米中的黄曲霉毒素B_1(AFB_1)降解,测定霉菌的致死量和毒素的脱除量。【结果】体外试验中,微波辐照、紫外线照射和臭氧熏蒸组合后对接种平板表面的霉菌孢子大多表现出明显的协同杀灭效应,最优的灭活组合是MW-UV/O_3。体内试验中,MW-UV/O_3组合方式可使染菌玉米表面的霉菌孢子致死量对数值达3.03。紫外线辐照和臭氧熏蒸串并联组合处理对染毒玉米中AFB_1的降解效果优于单一处理,且UV/O_3组合AFB_1含量较低,与未进行任何处理的染毒玉米相比降低了63.6%;微波辐照预处理对UV/O_3降解AFB_1无增效作用。【结论】与单一处理相比,MW-UV/O_3组合处理能发挥协同作用,有效降低霉变玉米的霉菌孢子数量和AFB_1含量,且不会引起玉米品质的显著改变。

【Objective】To provide new pathways for sterilization and detoxification of moldy maize,the synergistic effects of combined application of microwave（MW）,ultraviolet（UV）and ozone（O3）on mold spores inactivation and aflatoxin degradation were studied.【Method】On the basis of single factor tests,MW,UV and O3 were combined in series（-,treatments were carried out one by one）or in parallel（/,treatments were carried out simultaneously）,by which the mold spores on the surface of inoculated plate and mold-contaminated maize were inactivated and the aflatoxin B1 in aflatoxin-contaminated maize was degraded.Then,the inactivated amounts of mold spores and removal rates of aflatoxin were determined.【Result】In vitro,synergistic inactivation effects of combined applications of MW,UV and O3 on the mold spores on surface of inoculated plate were obtained.The most effective treatment was MW-UV/O3.In vivo,MW-UV/O3 treatment resulted in 3.03 lg CFU/g inactivation of mold spores on the mold-contaminatedmaize surface.The combinations of UV and O3 in serious or in parallel were more effective to degrade aflatoxin B1 in aflatoxin-contaminated maize than any single application.The aflatoxin B1 content in UV/O3 treatment was lower than that in untreated aflatoxin-contaminated maize.UV/O3 treatment resulted in63.6%reduction in aflatoxin B1 content.However,MW pretreatment did not enhance aflatoxin B1 degradation in UV/O3 treatment.【Conclusion】Compared to single applications,MW-UV/O3 treatment exhibited synergistic effects,which could effectively reduce mold spores and degrade aflatoxin B1 in moldy maize and avoid significant deterioration in maize quality.