Leonotis nepetifolia Flower Bud Extract Mediated Green Synthesis of Silver Nanoparticles, Their Characterization, and In Vitro Evaluation of Biological Applications

Abstract

Biosynthesis of silver nanoparticles (AgNPs) using the green matrix is an emerging trend and is considered green nanotechnology because it involves a simple, low-cost, and environmentally friendly process. The present research aimed to synthesize silver nanoparticles from a Leonotis nepetifolia (L.) R.Br. flower bud aqueous extract, characterize these nanoparticles, and perform in vitro determination of their biological applications. UV-Vis spectra were used to study the characterization of biosynthesized L. nepetifolia-flower-bud-mediated AgNPs (LnFb-AgNPs); an SPR absorption maximum at 418 nm confirmed the formation of LnFb-AgNPs. The presumed phytoconstituents subjected to reduction in the silver ions were revealed by FTIR analysis. XRD, TEM, EDS, TGA, and zeta potential with DLS analysis revealed the crystalline nature, particle size, elemental details, surface charge, thermal stability, and spherical shape, with an average size of 24.50 nm. In addition, the LnFb-AgNPs were also tested for antimicrobial activity and exhibited a moderate zone of inhibition against the selected pathogens. Concentration-dependent antioxidant activity was observed in the DPPH assay. Further, the cytotoxicity increased proportionate to the increasing concentration of the biosynthesized LnFb-AgNPs with a maximum effect at 200 μg/mL by showing the inhibition cell viability percentages and an IC50 of 35.84 μg/mL. Subsequently, the apoptotic/necrotic potential was determined using Annexin V/Propidium Iodide staining by the flow cytometry method. Significant early and late apoptosis cell populations were observed in response to the pancreatic ductal adenocarcinoma (PANC-1) cell line, as demonstrated by the obtained results. In conclusion, the study’s findings suggest that the LnFb-AgNPs could serve as remedial agents in a wide range of biomedical applications.

Myco-Nanofabrication of Silver Nanoparticles by Penicillium brasilianum NP5 and Their Antimicrobial, Photoprotective and Anticancer Effect on MDA-MB-231 Breast Cancer Cell Line

“…During the MTT assay, the yellow colored MTT reagent reacted with mitochondrial enzyme succinate dehydrogenase, which is released from cancer cells after the cell’s death, resulting in the formation of bluish-purple formazan crystals. Since the MTT assay is a colorimetric assessment, the results were recorded in absorbance at 570 nm, based on the color intensity, the cell viability was recorded and compared to the control [ 53 ]. Similar results were reported by Gurunathan et al [ 36 ], who biosynthesized AgNPs from Bacillus tequilensis and Calocybe indica that inhibited MDA-MB-23 cell proliferation with an IC 50 of 10 μg/mL and 2 μg/mL, respectively.…”

Biological Characterization of Cleome felina L.f. Extracts for Phytochemical, Antimicrobial, and Hepatoprotective Activities in Wister Albino Rats

“…Worldwide, about 25% of prescribed drugs are obtained from plants, where, at present, about 121 active phyto-compounds are in use. The World Health Organization (WHO) has emphasized the basics and essentials of the 252 drugs; while 11% are tremendous of plant origin, polyphenols play a pivotal role in the maintenance of cellular antioxidant status by reducing free radicals, which inactivates inflammatory cytokines and production of chemokines and, as well, minimizes the generation of reactive oxygen species (ROS) and lipid peroxidation [19,20]. The extraction yield varies in accordance with the purity of the crude compound and the polarity of the solvent [21].…”

“…An elemental analysis of leaves powder was carried out to determine the elemental composition. The mass % of elements was determined by generating the spectra of the various micro and macro mineral elements using energy-dispersive X-ray spectroscopy (EDX) (JSM-IT 500LA, Tokyo, Japan) [19].…”

Investigation of In Vitro Anticancer and Apoptotic Potential of Biofabricated Silver Nanoparticles from Cardamine hirsuta (L.) Leaf Extract against Caco-2 Cell Line

“…The first sign of C-AgNP synthesis was color change after 24 h dark incubation. Centrifugation at 10,000 rpm for 20 min and air-drying produced C-AgNPs [54].…”