Synthesis of copper oxide nanoparticles using capsular polymeric substances produced by Bacillus altitudinis and investigation of its efficacy to kill pathogenic Pseudomonas aeruginosa

Abstract

Clinically relevant antibiotic-resistant bacteria are appeared to be hard or impossible to treat using conventional antibiotics. In this context, copper oxide nanoparticles (CuO NPs) with latent and flexible character showed remarkable antimicrobial activity against pathogenic Pseudomonas aeruginosa. Minimum inhibitory concentration (<1 mcg/ml) and minimum bactericidal concentration (∼3 mcg/ml) for synthesized CuO NPs were predicted, comparable to the available antipseudomonal antibiotics. Green synthesis of CuO NPs was executed using capsular polymeric substance (CPS) extracted from a marine Bacillus altitudinis SORB11.The compound CPS containing mannose, glucose and galactose was compact and agglomerated in nature with a molecular weight of 1.247 × 103 Da. Crude CPS was effectively used as a coating and stabilizing agent for the synthesis of CuO NPs. The synthesized uniform, spherical CuO NPs showed a face-centered cubic cuprous oxide with a cuprite structure that appeared in crystalline planes. This present study was demonstrated successfully synthesized CuO NPs using an eco-friendly synthesis technique and ultimately, showed a significant level of antibacterial activity against pathogenic Pseudomonas aeruginosa.