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

Abstract

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).

Keywords

• anti-mold activity
• bacillus
• screening
• fusarium graminearum
• cereals
• oils and foods
• antimicrobial peptide