Microbe-mediated synthesis of antimicrobial semiconductor nanoparticles by marine bacteria

Development of bio-mediated synthesis of CdS nanoparticles is one of the important fields in nanoparticles. The present investigation demonstrates the eco-friendly synthesis of cadmium sulfide nanoparticles using Enterococcus sp. (RMAA). The formation of an intense peak at 410 nm in the UV–Vis spectrum reveals the synthesis of CdS nanoparticles. The crystalline natures of the synthesized CdS nanoparticles were identified by X-ray diffraction assay. The scanning electron microscope analysis shows the formation of spherical-shaped CdS nanoparticles with a size range of about 50–180 nm. Fourier transform infrared spectrum shows that the synthesized CdS nanoparticles are capped with bimolecular compounds which are responsible for the reduction of cadmium sulfate to sulfide nanoparticles. The resulting CdS nanoparticles were tested for antibacterial activity using agar well diffusion method against the test cultures of Serratia nematodiphila, Escherichia coli, Klebsiella planticola, Vibrio sp. and Planomicrobium sp. having good zone of inhibition. The fungicidal activity of CdS nanoparticles against pathogenic fungus Aspergillus niger and Aspergillus flavus produced a good zone of inhibition. The novel green chemistry approach is an eco-friendly and reliable process and suitable for large-scale production.