Streptomyces peucetius M1 and Streptomyces lavendulae M3 Soil Isolates as a Promising Source for Antimicrobials Discovery

Abstract

The ever-increasing fatality due to the surge of drug resistance has demanded the development of therapeutic metabolites with novel modes of mechanism. Despite the discovery of new antimicrobials, antibiotic resistance is increasing at an alarming rate. The emergence of novel molecules is necessary for targeting the Multidrug (MDR) and Pan-Drug resistant (PDR) pathogens which are the principal cause of life-threatening infections. Streptomyces strains commonly found in the soil produce secondary metabolites which have outstanding potential for being an antifungal and antibacterial agent. This study aims to isolate, identify, and characterize Streptomyces strains isolated from soil and extract their crude metabolites to determine their hidden therapeutic property. Out of four isolates identified, Streptomyces peucetius and Streptomyces lavendulae have shown significant antimicrobial activity against test organisms. To further determine the activity of their extracts GC-MS analysis, and MIC, as well as radical scavenging activity, were determined. GC-MS analysis revealed the presence of compounds 2,3-butanediol, 1-methyl-2-pyrrolidone-4-carboxamide, and L-Lactic acid which are frequently associated with potent antimicrobial nature. The most vulnerable pathogen to M1 extract was Candida albicans with a MIC value of 7.8125 μg/mL while the susceptible bacteria to M3 extract included Staphylococcus aureus with a MIC value of 3.90 μg/mL. The data obtained for antioxidant activity in the case of metabolic extracts M1 and M3 had an IC50 value of 43.17 µg/mL and 22.65 µg/mL respectively. The above findings hint at the unrealized potential of Streptomyces strains.