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The aim of this study was to investigate in vitro antioxidant, anti-inflammatory and cytotoxic activities of the petroleum ether, ethyl acetate, methanol and aqueous extracts obtained from leaves of Drypetes sepiaria (Euphorbiaceae). Total phenolic and flavonoid contents of these crude extracts were determined as gallic acid and quercetin equivalents, respectively. In in vitro antioxidant method, methanol extract exhibited higher free radical scavenging activity compared to standard compound, ascorbic acid with IC 50 of 95.43µg/ml (DPPH) and 67.05µg/ml (ABTS). Methanol extract was able to inhibit inflammation by in vitro about 85-90% (HRBC stabilization method) and in vivo about 40-45% (Paw oedema method) anti-inflammatory assays compared to standard produced 50.04% at 6h period. In cytotoxicity assay (MTT assay) methanolic extract exhibited IC 50 of 10µg/ml. In apoptosis (flow cytometric assay), the control group showed normal caspase 3 activity in the SiHa cells which was 0.24%, and increased up to 40% after treatment.

The use of Boswellia ovalifoliolata bark extract for the synthesis of zinc oxide nanoparticles (ZnO NPs) with benefits of eco-friendliness, low cost and compatibility for pharmaceutical and biological applications. In this paper, we report the biosynthesis of zinc oxide nanoparticles using plant extract and its application for the detection of picric acid (PA). The synthesized ZnO nanoparticles were characterized using UV-Vis spectroscopy, scanning electron microscopy (SEM), X-ray diffraction pattern (XRD), fourier transform infrared spectroscopy (FT-IR) and fluorescene spectroscopy. ZnO NPs in aqueous solution shows maximum absorption bands at 278 nm and fluorescence emission at 317 nm. The fluorescence emission of zinc oxide nanoparticle shows high selectivity towards picric acid (PA) and can be used as a fluorescent probe for the detection of PA via fluorescence quenching mechanism. The fluorescence quenching mechanism of picric acid may be due to the electron transfer process between ZnO NPs and picric acid which is confirmed by cyclic voltammetry (CV). The quenching efficiency of nanoparticle was calculated using Stern-Volmer equation. The limit of detection was found to be 1.83 µM for picric acid. The fluorescence property of the ZnO NPs can be utilized for cell imaging application as biosensors and also in the field of drug delivery.

In this study, the authors synthesised gold nanoparticles (Au NPs) by a green approach using an aqueous extract of empty cotton boll peels (ECBPs) which was rapid, simple and inexpensive eco-friendly method compared to chemical and physical methods. The ECBP aqueous extract played a vital role in the reduction of Au +3 ions into Au NPs which was further confirmed by analytical characterisation. The phase purity and crystallinity of Au NPs were confirmed by X-ray diffraction analysis. The characteristic functional groups of synthesised Au NPs were identified by Fourier transform infrared analysis. The surface morphology and topography of Au NPs were studied by scanning electron microscopy and transmission electron microscopy analysis. Size with dispersion stability of Au NPs was determined by dynamic light scattering and zeta potential studies. In this study, the authors performed a catalytic activity of Au NPs using different pollutant organic dyes such as methylene blue and methyl orange. It also showed good antioxidant activity compared to standard ascorbic acid by using the standard 1,1-diphenyl-2-picryl-hydrazil method. Hence, this study concluded that ECBP mediated Au NPs could act as a promising material for degradation of dyes and antioxidant activity.