A sustainable approach to prepare green synthesis of copper nanoparticles of Bauhinia variegata & Saussurea lappa: Unveiling in-vitro anti-obesity applications

Abstract

Nanoparticles have different shapes and sizes between the range of 1–100 nm, which show advantages for stabilizing compounds, higher carrier capacity, and lower costs. Metal nanoparticles such as copper, gold, silver, and zinc are favorable components for various applications due to their interesting properties. In the present study, nanoparticles were synthesized by reduction with flower extracts of Bauhinia variegate &Saussurea lappa that were used to stabilize the copper nanoparticles. Furthermore, the characterization of plants synthesized copper nanoparticles was carried out through UV–visible dynamic light scattering. Additionally, morphological characterization of nanoparticles was confirmed by scanning electron microscopy and energy dispersive X-ray spectroscopy confirmed the elemental composition of copper nanoparticles. Powder X-ray diffraction was conducted for the analysis of crystallinity, purity, and crystal size of plant-synthesized copper nanoparticles. The average particle size was evaluated and exhibited the particle size at the peak of 8.721 nm and 98.03 nm for flower extracts of Bauhinia variegate &Saussurea lappa copper nanoparticles. The Fourier Transform Infrared spectrum was taken to scrutinize the various functional groups that were responsible for the reduction of the copper ions. The antimicrobial results against the bacterial strains with the positive test results of the zone of inhibition were for Bauhinia variegate (17 mm, 18 mm, 19 mm, and 18 mm) and Saussurea lappa (17 mm, 19 mm, 18 mm, and 18 mm) respectively for plants synthesized copper nanoparticles against the Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa. Lipase inhibition assay and Amylase inhibition assay with different concentrations (20 μg/mL to 100 μg/mL) for Bauhinia variegate &Saussurea lappa (12.34 %–59.67 % and 10.50 %–47.01 %) and (34.52 %–89.02 % and 22.34 %–56.45 %) confirmed the anti-obesity and anti-diabetic activities of plants extract synthesized copper nanoparticles.