Study of the antimicrobial activity of endophytic Streptomyces strains isolated from Crinum latifolium

Abstract

We isolated three strains of endophytic Streptomyces from Crinum latifolium. Preliminary screening of antimicrobial activity showed one strain (SS004) with antibacterial activity on SFM medium. SS004 was identified as Streptomyces diastaticus subsp. ardesiacusbased on 16S rRNA nucleotide sequence analysis. Antimicrobial activity produced by SS004 appeared merely after 18 hours of culture in SFM medium proving that the biosynthesis of the antimicrobial compounds was controlled in the same type as those as in other Streptomyces strains. SS004 produced more antimicrobial compound at 28 oC than at 37 oC. SS004 showed diversity in antimicrobial compound production on different media, notably on FM3 medium which has antibacterial activity against several antibioticresistant bacteria. In conclusion, endophytic Streptomyces strains are remarkable for their production of antimicrobial compounds.