Oligomycins A and C, major secondary metabolites isolated from the newly isolated strain Streptomyces diastaticus

Abstract

During the screening program for fungicides, one actinomycete strain ECO 00047 was isolated with the potential activity against fungus. According to the morphology and analysis of the nucleotide sequence of the 16S rRNA gene (1500 bp) this isolate was identified as Streptomyces diastaticus. The active compounds were separated by silica gel column chromatography, Sephadex LH-20 gel filtration and then purified by flash chromatography on C18 (20-45 microm). The chemical structure of the bioactive compounds I and II were elucidated, based on the spectroscopic data of MS, IR, UV, 1H-NMR, 13C-NMR and X-ray single crystal diffraction analysis. Compounds I and II were identical with oligomycins A and C, the macrolide antibiotics which have been known to be produced by Streptomyces diastatochromogenes, S. libani and S. avermitilis. The two compounds exhibited a strong activity against Aspergillus niger, Alternaria alternata, Botrytis cinerea and Phytophthora capsici but no activity toward bacteria. Although the two above antibiotics were known, their isolation has so far not been reported from S. diastaticus.

The Potential of Streptomyces as Biocontrol Agents against the Rice Blast Fungus, Magnaporthe oryzae (Pyricularia oryzae)

“…exhibited antifungal activity against M. oryzae (Appendix 1). The antibiotic Oligomycin A was first isolated from S. diastatochromogenes and was found to be active against several other phytopathogenic fungi in addition to M. oryzae such as Botrytis cinerea, Cladosporium cucumerinum, Colletotrichum lagenarium, Phytophthora capsici, Alternaria alternata , and Aspergillus niger (Smith et al, 1954; Kim et al, 1999; Yang et al, 2010). Oligomycin A’s ability to control the development of rice blast was evaluated in the greenhouse and the results showed that rice plants treated with Oligomycin A (50 μg/mL) had reduced lesions.…”

Diversity Utility and Potential of Actinobacteria in the Agro-Ecosystem

“…The compound had no effect on seed germination and seedling development of the test plant species (Bordoloi et al 2002). Oligomycins A and C, are macrolide antibiotics produced by the actinobacterium Streptomyces diastaticus, and exhibit a strong activity against Aspergillus niger, Alternaria alternata, Botrytis cinerea and Phytophthora capsici (Yang et al 2010). The metabolites produced by Actinobacteria in relation to plant disease suppression are listed in Table 2.2. Besides antibiotic molecules, commercial biocontrol formulations containing Actinobacteria as active ingredients are also available as tools of plant health management.…”

Biologically active secondary metabolites from Actinomycetes

“…Oligomycins A and C are macrolide antibiotics that demonstrate strong antifungal activity against Aspergillus niger, Alternaria alternata, Botrytis cinerea and Photophthora capsici. They do not exhibit any antibiotic activity [89].…”