[关键词]
[摘要]
为了快速检测粮食及加工品中真菌、细菌等微生物的污染及生长的状况,选用了过氧化氢酶活性检测与经典的平板菌落计数检测进行比对试验。结果表明,对灰绿曲霉菌(Aspergillus glaucus)、黄曲霉菌(Aspergillus flavus)和枯草芽孢杆菌(Bacillus subtilits)等与粮食及加工品的储藏和流通品质及安全性密切相关的菌种进行梯度稀释菌悬液检测时,过氧化氢酶法检测值的相对偏差较小,且线性相关性系数均达到或大于0.99,其检测值与平板菌落计数法检测值的相关性系数均大于0.95。对于不同微生物污染程度的粮食及加工品,两种方法的检测数值变化趋势完全一致。相对于同一带菌量的样品,当粮食或加工品中的微生物处于生长状态时,过氧化氢酶检测法显示出更高的检测灵敏度,酶活性检测值超过微生物非生长态下同一带菌量样品检测值2倍以上。因此,过氧化氢酶检测法可以作为检测粮食及加工品中微生物污染及生长状况的有效手段。
[Key word]
[Abstract]
To detect contamination and growth of fungi, bacteria, and other microorganisms in grain and its processed products rapidly, a comparative experimental study was conducted by using catalase activity detection and plate culture count methods. For this purpose, gradient dilutions were used in Aspergillus glaucus, Aspergillus flavus, Bacillus subtilis, and other microbial suspensions, which are closely related to the quality and safety of grain and its processed products during storage and circulation. The results showed that for the method involving detection of catalase activity, deviations were relatively small, all linear correlation coefficients were equal to or more than 0.99, and the correlation coefficients between the measured values using this method and those obtained using the plate count method were greater than 0.95. For grain and its processed products with different degrees of microbial contamination, the change in the trend of the measured values using the two methods was consistent. For samples with the same type of microorganisms in grain and its processed products, the catalase activity detection method showed relatively high sensitivity. Additionally, when these microorganisms were in the growth state, the values for enzyme activity were two times higher than that when they were not in the growth state. Therefore, the method based on catalase activity detection is an efficient method to detect contamination and growth of microorganisms in grain and its processed products.
[中图分类号]
[基金项目]
国家自然科学基金项目(31271948);国家重点基础研究发展计划(973计划)(2013CB127804);河南省教育厅自然科学项目(14A180004)