[Diversity and antimicrobial activities of actinomycetes from pesticide-contaminated spots in Shandong Peninsula].

ABSTRACT

OBJECTIVE: In order to study diversity and find antimicrobial activities of actinomycetes from pesticide-contaminated spots in Shandong Peninsula. METHODS: The phylogenetic analysis of 154 isolated strains was done based on 16SrDNA sequences. Antimicrobial activities of 10 non-Streptomyces strains were tested by using cylinder-plate method and hypha growth rate method. RESULTS: Among the strains, 154 strains belonged to 7 families, 8 genera Streptomyces (87.01%), Kocuria, Microbacterium, Nocardiopsis, Knoellia, Pseudonocardia, Micromonospora, Actinoplanes. The fermentation broths of 10 non-Streptomyces strains had inhibitory actives against all tested phytopathogenic fungi (Botrytis cinerea, Fusarium oxysporum f. sp. niveum, Gibberella zeae, Sclerotinia sclerotiorum, Colletotrichum gloesporioides) and bacteria (Staphylococcus aureus, Bacillus subtills, Bacillus cereus, Escherichai coli, Pseudomonas aeruginos) , especially Microbacterium oxydans JN853773 and Kocuria rosea JN192402 had strong inhibitory effects. CONCLUSION: Abundant diversity of actinomycetes existed in pesticide contaminated spots in Shandong Peninsula. Microbacterium oxydans JN853773 and Kocuria rosea JN192402 showed high antimicrobial activities and could be further exploited.