Green synthesis of Cu nanoparticles using Curcuma longa extract and their application in antimicrobial activity.

• A novel green synthesis method is employed for the synthesis of copper nanoparticles. • The average size of the synthesized Cu nanoparticles is in the range of 5–25 nm. • The obtained nanoparticles have shown good antibacterial activity against gram-positive and gram-negative bacteria. In the present report, for the first time aqueous extract of Curcuma longa powder is used for the synthesis of Copper nanoparticles (Cu NPs) using a simple and cost effective method. Morphology, size, crystallinity, composition and microstructure of the synthesized Cu Nps are studied. Size of the particles are in the range of 5–20 nm. In addition to the above, antibacterial activity of the obtained Cu NPs is tested for both gram-positive and gram-negative microorganisms. Zone of inhibition of Cu NPs for gram positive bacteria is more compared to gram negative bacteria. The current work on green synthesis of metallic nanoparticles can be considered as an alternative method to avoid the usage of hazardous compounds and bitter reaction conditions in the production of metal nanoparticles. The obtained Cu NPs with their distinctive structural properties and effective biological effects can be used in applications viz. antimicrobial, antifungal, anticancer activity. [ABSTRACT FROM AUTHOR]