Aims: Characterization of antimicrobial metabolites of novel Streptomyces sp. UK-238.
Background: Novel antimicrobial drug discovery is urgently needed due to emerging multi antimicrobial
drug resistance among pathogens. Since many years, natural products have provided the basic
skeletons for many therapeutic compounds including antibiotics. Bioprospection of un/under explored
habitats and focussing on selective isolation of actinobacteria as a major reservoir of bio and chemodiversity
has yielded good results.
Objective: The main objectives of the study were the identification of UK-238 by 16S rDNA sequencing
and antimicrobial metabolite fingerprinting of culture extracts.
Methods: In the present study, a promising isolate, UK-238, has been screened for antimicrobial activity
and metabolite fingerprinting from the Himalayan Thano Reserve forest. It was identified by 16S
rDNA sequencing. Ethyl acetate extract was partially purified by column chromatography. The pooled
active fractions were fingerprinted by GC-MS and compounds were tentatively identified by collated
data analysis based on Similarity Index, observed Retention Index from Databases and calculated Retention
Results: UK-238 was identified as Streptomyces sp. with 98.4% similarity to S. niveiscabiei. It exhibited
broad-spectrum antibacterial and antifungal activity. The GC-MS analysis of active fractions of
ethyl acetate extract showed the presence of eighteen novel compounds, some with antimicrobial activity,
belonging to four major categories- alcohols, alkaloids, esters and peptide.
Conclusion: The study confirms that bioprospection of underexplored habitats can elaborate novel bio