Bioprospection and secondary metabolites profiling of marine Streptomyces levis strain KS46

Bidhayak Chakraborty; Raju Suresh Kumar; Abdulrahman I Almansour; Pethaiah Gunasekaran; Sreenivasa Nayaka

doi:10.1016/j.sjbs.2021.11.055

Bioprospection and secondary metabolites profiling of marine Streptomyces levis strain KS46

Saudi J Biol Sci. 2022 Feb;29(2):667-679. doi: 10.1016/j.sjbs.2021.11.055. Epub 2021 Dec 1.

Authors

Bidhayak Chakraborty¹, Raju Suresh Kumar², Abdulrahman I Almansour², Pethaiah Gunasekaran³, Sreenivasa Nayaka¹

Affiliations

¹ P.G. Department of Studies in Botany, Karnatak University, Dharwad 580003, Karnataka, India.
² Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
³ College of Pharmacy, Korea University, Sejong, Republic of Korea.

Abstract

The quest for novel broad spectrum bioactive compounds is needed continuously because of the rapid advent of pathogenic multi drug resistant organisms. Actinomycetes, isolated from unexplored habitats can be a solution of this problem. The motive of this research work was isolation of actinomycetes having potential antimicrobial activities from unexplored regions of Devbag and Tilmati beach. The isolated actinomycetes were screened against pathogenic microbes for antimicrobial activities through cross streak method. Enzyme production activity was checked for these actinomycetes for amylase, protease, cellulase and lipase enzymes. Further antimicrobial activity of ethyl acetate extract of the potent strain KS46 was performed. The strain KS46 was identified with 16S rRNA gene sequencing and secondary structure was analysed. Gas chromatography-Mass spectrometry (GC-MS) profiling was conducted to ascertain the presence of bioactive metabolites in the ethyl acetate extract. The collected samples were pre-treated and 70 actinomycetes were isolated. The Streptomyces sp. strain KS46 showed the best antimicrobial activity in primary screening. Ethyl acetate extract of the strain KS46 revealed antimicrobial activity against S. aureus, B. subtilis, B. cereus, E. faecalis, K. pneumoniae, E. coli, S. flexneri, C. albicans and C. glabrata. The 16S rRNA gene sequencing identified the strain KS46 as Streptomyces levis strain KS46. The GC-MS metabolite profiling of the ethyl acetate extract revealed the availability of 42 compounds including fatty acid esters, fatty acid anhydrides, alkanes, steroids, esters, alcohols, carboxylic ester, etc. having antibacterial, antifungal, antiproliferative, antioxidant activities. This study indicated that Devbag and Tilmati beaches being untapped habitats have enormous diversity of promising antimicrobial metabolite producing actinomycetes. Therefore, further exploration should be carried out to characterize the potential actinomycetes, which can be optimistic candidates for generation of novel antimicrobial drugs.

Keywords: 16S rRNA gene sequencing; Actinomycetes; Antimicrobial; Devbag and Tilmati beaches; Enzymes; GC–MS; Streptomyces levis.