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In reported work, zinc oxide nanoparticles (ZnONPs) had been synthesised by a green method using aqueous extract of Cannabis sativa leaves. A facile, eco-friendly, time saving and beneficial procedure for the preparation of metal nanoparticles had been developed. UV-visible spectroscopy, Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to characterise the ZnONPs composition, their shape, size and crystallinity. Ultraviolet-visible spectra showed the absorbance band between 300 and 400 nm, which indicated the synthesis of stable ZnO nanoparticles. Average size of ZnONPs was calculated from XRD as 46 nm. SEM and EDX spectra confirmed the synthesis of spherical shaped ZnONPs. FTIR spectra showed that different functional groups were present in aqueous extract of plant's leaves, which acted as reducing agents in the formation of stable ZnONPs. The value of DPPH radical inhibition percentage shown by ZnONPs was 88 ± 0.08% at 1500 µg/ml concentration revealing its good antioxidant activity. The total antioxidant activity calculated for ZnONPs was 0.521 ± 0.34 against BHT as standard. Total phenolic contents for ZnONPs was calculated to be 292.60 ± 1.12 mg/g GAE. Then the synthesised ZnONPs were utilised as catalyst for the removal of harmful organic dyes methylene blue (MB) and Congo red (CR). Various factors like adsorbent dosage, dye concentration, pH and temperature were studied and optimised for maximum removal of dyes. Pseudo-first-order model was followed for adsorption kinetics of both dyes. Adsorption isotherms were also assessed using Freundlich and Langmuir isotherm models. Hence, green approach was easy and cost effective for the removal of organic dyes and found as efficient antioxidant in current study. [ABSTRACT FROM AUTHOR]

Many compounds containing sulfur and phosphorous are present in wastewater of various industries like food processing, paper making, etc. The higher level of phosphate and sulfate ions causes many problems in everyday life. Based on this, nickel monometallic and nickel-cobalt bimetallic nanoparticles were synthesized using leaves extract of Coix lacryma-jobi L. and applied for sulfate and phosphate ions removal. UV-Vis. spectroscopy, fourier transformed infrared spectroscopy; scanning electron microscopy; X-ray diffraction, and energy-dispersive X-ray spectroscopy were used as characterizing techniques for synthesized nanoparticles. UV spectra for Ni nanoparticles showed the absorption band in the 380–400 nm range, while for Ni-Co bimetallic nanoparticles was noticed at 396 nm and 513 nm. Different functional groups were observed in FTIR spectra of leaves extract which acted as reducing and capping agents to form stable NPs. Different factors like adsorbent dosage, pH, temperature, adsorbate concentration, and time were optimized for maximum removal of sulfate and phosphate anions. The antioxidant potential of prepared nanoparticles was assessed by three different methods. The kinetics, thermodynamics, and adsorption isotherms were also studied for these ions removal. In the current study, the green approach was easy, time-saving and proved to be beneficial to remove sulfate and phosphate anions from wastewater. The leaves extract of Coix lacryma-jobi L. were employed for the synthesis of nickel monometallic and nickel-cobalt bimetallic nanoparticles and employed for the removal of sulfate and phosphate ions from aqueous solution. Antioxidant potential of biosynthesized nanoparticles was also assessed. Hence, the biosynthesized nanomaterial found to be novel adsorbent for removal of sulfate and phosphate from waste water. This research work has not been previously reported in literature. [ABSTRACT FROM AUTHOR]

In this study, green synthesis of monometallic (Ag) and bimetallic (Ag-Ni) nanoparticles is carried out. UV-Visible spectra illustrated peaks at 463 and 429 nm for monometallic and bimetallic nanoparticles. FTIR spectra analysis revealed the presence of different functional groups. SEM and EDX elaborated on the morphology and indicate the presence of respective elemental peaks. XRD data calculations predicted the size of monometallic and bimetallic to be 42 and 25 nm. In the end, the biosynthesized nanoparticles are used as a spectrophotometric probe for the determination of cupric ions. Different parameters are studied and optimized on a standard aqueous solution. Monometallic nanoparticles showed an optimum response in a slightly alkaline medium within 12.5 min of contact time for 8 μM analyte concentration. While bimetallic nanoparticles attained this target in a shorter contact time with a higher concentration value. Then these optimized conditions are utilized for the determination of cupric ions in real water samples. [ABSTRACT FROM AUTHOR]

The phytochemical investigation of the ethylacetate-soluble fraction of Caryopteris odorata (Ham. ex Roxb.) led to the isolation of four new iridoid glucosides (1–4): 8-O-trans-cinnamoyl caryoptoside (1), 8-O-trans-cinnamoyl shanzhiside methylester (2), 8-O-trans-cinnamoyl mussaenoside (3) and 8-O-cafeoyl massenoside (4). The structures of these compounds were determined by FAB-MS, IR, 1D and 2D-NMR spectroscopy and by comparing with the published data of the closely related compounds. The antioxidant potential of the isolated iridoids (1–4) was evaluated relative to conventionally used standards and these molecules exhibited good antioxidant potential. Moreover, their inhibitory potential was also screened against three enzymes, namely acetyl cholinesterase, butyrylcholinesterase and lipoxygenase. These iridoid glucosides were found to be inactive against acetyl and butyrylcholinesterases but active against lipoxygenase. [ABSTRACT FROM AUTHOR]