Comparitive study on the antioxidant, anticancer and antimicrobial property of Agaricus bisporus (J. E. Lange) Imbach before and after boiling

In this study, ethanol extracts of an edible mushroom Agaricus bisporus, before and after boiling were investigated for antioxidant, anticancer and antimicrobial activities. To confirm the total antioxidantactivity, ABTS, DPPH free radical-scavenging assay was carried, along with total phenolic and flavonoid concentration. In measuring ABTS and DPPH free radical scavenging activities, scavenging activity wasfound to be similar in both the extracts. Total flavonoids were 16.4±0.5 and 15.2±0.2 mg/g (Quercetin equivalent), the phenolics were 90.2±0.6 and 70.6±0.1 mg/g (Catechin equivalent) in raw and boiled extract, respectively. A. bisporus extracts inhibited cell proliferation of HL-60 leukemia by the induction of apoptosis. In addition, A. bisporus extracts exhibited antibacterial activity against both gram positiveand gram negative bacteria, as well as anticandidal activity against Candida albicans. Therefore, A. bisporus could be considered as a functional food with antimicrobial, anti-oxidative and antiproliferative activity

Optically pumped room-temperature GaAs nanowire lasers

Near-infrared lasers are important for optical data communication, spectroscopy and medical diagnosis. Semiconductor nanowires offer the possibility of reducing the footprint of devices for three-dimensional device integration and hence are being extensively studied in the context of optoelectronic devices. Although visible and ultraviolet nanowire lasers have been demonstrated widely, progress towards room-temperature infrared nanowire lasers has been limited because of material quality issues and Auger recombination. (Al)GaAs is an important material system for infrared lasers that is extensively used for conventional lasers. GaAs has a very large surface recombination velocity, which is a serious issue for nanowire devices because of their large surface-to-volume ratio. Here, we demonstrate room-temperature lasing in core-shell-cap GaAs/AlGaAs/GaAs nanowires by properly designing the Fabry-Pérot cavity, optimizing the material quality and minimizing surface recombination. Our demonstration is a major step towards incorporating (Al)GaAs nanowire lasers into the design of nanoscale optoelectronic devices operating at near-infrared wavelengths. © 2013 Macmillan Publishers Limited. All rights reserved