Antagonistic Behavior of Streptomyces chartreuse against Pathogenic Bacteria in Ricinus communis L.

Abstract

ABSTRACT: Antibiotics are a crucial tool in modern medicine and have saved countless lives by effectively treating a wide range of bacterial infections. The microbial antibiotic have several biotechnological applications viz. agriculture, pharmaceuticals, food preservation, animal nutritions. The diverse array of applications and the various roles of bioactive metabolites produced by Actinomycetes have sparked a growing interest in the exploration of unique and unprecedented Actinomycetes strains. The Actinomycetes from soil ecosystem, marine ecosystem, rhizosphere of plant roots are also known to secrete novel antibiotics. In this context, the main objective of this research is to isolate and screen Actinomycetes strains that are capable of producing highly potent culturable secondary metabolites with novel antibacterial properties. These metabolites can potentially serve as biocontrol agents against Xanthomonas infections in Ricinus communis L., offering uncommon and innovative applications within the field of agriculture. All the Actinomycetes isolates were isolated from Mehsana regions of Gujarat an area of over 4,401 km2, with wide microbial diversity and can serve as a source for promising antibiotics producers. 7 rhizospheric soil samples were collected from various region sites viz. Ranasan, Mansa, Panchot, Gozariya, Kansa, Langhnaj, and Kherva. Total 76 antibiotic producing Actinomycetes isolates were obtained in Primary Screening. Based on the results of primary screening, potential morphologically diverse 3 isolates were selected for antibiotic production in liquid medium. FTIR analysis of three samples revealed distinct bands in the spectra. Sample-1 exhibited O-H (1347 cm^-1) and C-N (1191 cm^-1) groups. Sample-2 displayed O-H (3462 cm^-1), C-O (1043 cm^-1), and C=O (1736 cm^-1) groups. Sample-3 showcased O-H (3466 cm^-1), C=O (1737 cm^-1), C-N (1232 cm^-1), and C-O (1043 cm^-1) groups, providing valuable insights into their chemical compositions. The isolate BNPA72 gave best antibiotic production and was identified as Streptomyces chartreusis by 16 s rRNA gene sequencing method. The isolate Streptomyces chartreusis BNPA72 was able to inhibit the plant pathogen Xanthomonas, hence categorized as Biocontrol agents.