Background: The present paper describes a less time-consuming and eco-friendly method for the synthesis of silver nanoparticles (AgNPs) using an aqueous solution of silver nitrate and Amaranthus gangeticus Linn (Chinese spinach) leaf extract. The synthesized AgNPs which are to be used as an antimicrobial and Congo red dye is to be used as a toxic-degrading agent. Methods: AgNP was prepared by the reduction of silver nitrate solution by the leaf extract of Amarranthus Gangeticus Linn leaf extract in aqueous medium on heating for about 15 mins at 80°C in presence of one drop 0.05 (M) NaOH. Results: The size of the synthesized silver nanoparticles (AgNPs) using Amaranthus gangeticus Linn leaf extract and aqueous solution of silver nitrate (10 −3 M) are formed at their stable condition within the range of 11-15 nm. AgNPs are obtained by this process within a couple of minutes of reaction without using reducing and stabilizing agents or harsh conditions. High-resolution transmission electron microscope (HR-TEM), selected area electron diffraction (SAED), ultraviolet-visible (UV-VIS) spectroscopy, and Fourier transform infrared spectroscopy (FTIR) are used to characterize the prepared AgNPs which show that the nanoparticles are globular in shape and polycrystalline. The synthesized silver nanoparticles showed inhibitory activity towards Gram positive, Gram negative bacteria and fungus and also showed good Congo red dye-degrading agents. Conclusions:The overall outcome of this study suggests that green synthesis AgNPs hold promise as a potent antibacterial and antifungal agent. The particles obtained were also found to degrade toxic Congo red dye.

The photo physical properties of two mononuclear pentacoordinated copper(II) complexes formulated as [Cu(L)(Cl)(H2O)] (1) and [Cu(L)(Br)(H2O)] (2) HL = (1-[(3-methyl-pyridine-2-ylimino)-methyl]-naphthalen-2-ol) were synthesized and characterized by elemental, physicochemical, and spectroscopic methods. The density function theory calculations are used to investigate the electronic structures and the electronic properties of ligand and complex. The interactions of copper(II) complexes towards calf thymus DNA were examined with the help of absorption, viscosity, and fluorescence spectroscopic techniques at pH 7.40. All spectroscopy's result indicates that complexes show good binding activity to calf thymus DNA through groove binding. The optical absorption and fluorescence emission properties of microwires were characterized by fluorescence microscope. From a spectroscopic viewpoint, all compounds strongly emit green light in the solid state. The microscopy investigation suggested that microwires exhibited optical waveguide behaviour which are applicable as fluorescent nanomaterials and can be used as building blocks for miniaturized photonic devices. Antibacterial study reveals that complexes are better antimicrobial agents than free Schiff base due to bacterial cell penetration by chelation. Moreover, the antioxidant study of the ligand and complexes is evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical assays, which demonstrate that the complexes are of higher antioxidant activity than free ligand.

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Muscodor albus MOW12, an endophytic fungus isolated from Piper nigrum in Mawlong, Meghalaya, India, resembles some cultural and hyphal characteristics of previous isolates of Muscodor sp. In addition, it possesses about 99 % similarity in its ITS rDNA with other M. albus isolates and thus is nicely centered within the genetic tree to other Muscodor spp. This xylariaceae fungus effectively inhibits and kills certain plant pathogenic fungi by virtue of a mixture of volatile compounds that it produces. The majority of these compounds were identified by gas chromatography/mass spectrometry as small molecular weight esters, alcohols, and acids. The main ester components of this isolate of M. albus in its volatile mixture are acetic acid, ethyl ester; propanoic acid, 2-methyl-, methyl ester and acetic acid, 2-methylpropyl ester. This appears to be the first report of any M. albus strain from India.