Perilla frutescens (Linn.) Britt Leaves Extract Mediated Green Synthesis, Characterization, In Vitro Biological Activities and Embryo Toxicity of Copper Nanoparticles

This work aims to evaluate biological activities and toxicity of copper nanoparticles (CuNPs) synthesized from Perilla frutescens (Linn.) Britt leaves extract. Microscopic techniques showed the poly dispersed CuNPs with a size of 30-65 nm and high resolution X-ray diffraction (HR-XRD) revealed the face centered cubic Cu. CuNPs significantly inhibited the growth of few human pathogenic bacteria namely, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium and Bacillus cereus and a fungal pathogen, Alternaria alternata at 40 mu g/40 mu l concentration. Mode of action of CuNPs against the bacterial pathogens was demonstrated using biological transmission electron microscope (Bio-TEM). >60 % inhibition was observed against MCF-7 cells at 160 mu g/ml of CuNPs and the apoptotic morphology was confirmed using ethidium homodimer and casein staining. Finally, the toxicity of CuNPs was studied using zebrafish embryo and higher toxic effects were recorded even at 1.5 mu g/ml of CuNPs. Therefore, the toxicity of CuNPs must be thoroughly studied.