The plant extracts are known for their anti-inflammatory, antifungal, antiviral and antibacterial properties. The use of plant extracts in the preparation of bio-materials increases their biological application. In this concern, herein reporting an eco-friendly procedure which is also a simple and cost effective, for the synthesis of Zinc Oxide nanoparticles (ZnONPs) using Saussurea lappa plant root (rhizome) extract as a fuel. The prepared nanoparticles were confirmed using various characterization techniques. The Dynamic light scattering data showed 123.5 nm particle size with -99.9 mv zeta potential which indicates excellent stability of the particles. The peak at 541 cm−1 in the IR spectrum is assigned to the stretching frequency of the zinc-binding to oxygen. The X-ray diffraction peaks confirm the close association with JCPDS Data Card No: 36-1451. The FESEM data revealed a hexagonal wurtzite structure with a hexagonal shape of synthesized ZnO nanoparticles. The antibacterial studies indicate the gram-negative strains showed better inhibition activity than gram-positive strains. Among Fungal strains, Aspergillus niger and flavus, Fusarium oxysporum, and Rhizopus oryzae showed good inhibition activity at higher concentrations. The cytotoxic data indicates the 5 μg/mL of the ZnO particles showed cytotoxicity on the CHO cell line and with IC50 value 3.164 ± 0.8956 μg/mL.

The paper describes the synthesis and characterization of copper oxide nanoparticles (CuO NPs) using the mixture of plant rhizome extracts Ocimum sanctum and Saussurea lappa as a reducing agent. The prepared CuO nanoparticles are characterized and confirmed their formation based on data obtained from powder X-ray diffraction spectroscopy, Fourier Transmission Infrared, Ultraviolet-Visible spectra, Field Emission Scanning Electron Microscopy images, Energy Dispersive X-ray analysis and Dynamic light scattering techniques and data reveal that the average size of CuO Nps was 103.4 nm. The result of antibacterial and antifungal activities for concentrations 50, 100, and 170 ppm indicate that NPs may exhibit appreciable activity at higher (170 ppm) concentrations. The MTT cytotoxic assay studies of Chinese Hamster Ovary (CHO) cell lines showed a Half-maximal inhibitory concentration (IC₅₀) value of 4.14 ​μg/mL.