Isolation, characterization, and identification of bioactive metabolite from soil derived Streptomyces polyrhachis AS07

Abstract

The increasing stress caused by antibiotic resistance necessitates the need to explore novel and effective antimicrobial agents from actinomycetes which are often acknowledged for their capability to produce a variety of antibiotics. This study focuses on investigating the antimicrobial properties of the secondary metabolite synthesized by the soil resident Streptomyces polyrhachis AS07. The soil isolated strain was identified using 16S rRNA sequencing technology and phylogenetic analysis. Under appropriate laboratory conditions, the Streptomyces sp. produced sufficient yield of secondary metabolite for assessment of antimicrobial properties. The Gas Chromatography Mass Spectrometry chromatogram of the metabolite revealed abundant presence of antimicrobial constituents such as propionic acid, palmitic acid, and other compounds from tetrazolic and monocarboxylic groups. When tested against a broad range of Gram-positive and Gram-negative bacteria, the extracted metabolite exhibited appreciable antimicrobial activity with highest activity against S. aureus. Additionally, it also had potential antioxidant activity with an IC50 value of 5.50 μg/mL. The metabolite displayed highest antibiofilm activity against B. subtilis as well as successfully restricted the quorum sensing ability of C. violaceum. Furthermore, the extract significantly inhibited the swarming ability of P. aeruginosa upto 16.67 %. Conclusively, Streptomyces metabolite can be considered as a potent reservoir of bioactive molecules for industrial production with promising pharmaceutical applications.