粮油食品防霉微生物筛选及其活性物质初步研究

为开发新型防霉剂，降低粮油食品储藏、运输、流通等过程中霉变对其品质和食用安全的影响，研究筛选获得具有强防霉活性的微生物。采用抑菌圈法，以禾谷镰刀菌（Fusarium graminearum）为指示菌筛选具有防霉活性的菌株。利用形态学观察、生化特征鉴定和16S rDNA基因序列比对进行菌株鉴定；通过不同温度、pH和蛋白酶K处理对防霉活性物质进行初步分析。结果显示：通过初筛获得33株对禾谷镰刀菌具有强抑制活性的菌株，复筛后选择的7株菌归属为芽孢杆菌属（Bacillus）；活性物质分析发现7株菌的活性物质均不耐高温和强酸碱，同时蛋白酶K处理对其防霉效果没有明显影响，初步推断为肽类；通过抑菌谱测定发现菌株ASAG 62对常见霉菌（产黄青霉Penicillium flavum、黑曲霉Aspergillus Niger、赭曲霉Aspergillus ochre、黄曲霉Aspergillus flavus、禾谷镰刀菌F. graminearum）均具有良好的抑制效果。

Research on the Screening of Anti-mold Microorganisms in Cereals, Oils and Foods and their Bioactive Substances

In order to develop new anti-mold agents and reduce the effect of mildew on the quality and safety during storage, transportation, and circulation of cereals, oils and foods, microorganisms with strong anti-mold activity were screened in this study. Bacteriostasis method was applied and Fusarium graminearum was taken as indicator. Morphological observation, biochemical characterization and 16S rDNA gene sequences alignment were used to identify the strains. The anti-mold bioactive substances were analyzed in different temperatures, pH, and proteinase K treatment. After primary screening, 33 strains with strong inhibitory activity against F. graminearum were obtained. Seven strains were selected after secondary screening and classified as Bacillus. Through the analysis of bioactive substances, the anti-mold effects of the seven strains were not of high temperature and strong acid or base resistant, or obviously influenced by proteinase K treatment. It indicated that the bioactive substances were peptides. Finally, the strain ASAG 62 had good inhibitory effect on common molds (Penicillium flavum, Aspergillus Niger, Aspergillus ochre, Aspergillus flavus and F. graminearum).