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The stable and crystalline phase of different surfactants (CTAB, PEG and SDS) capped CeO 2 nanoparticles were directly synthesized by chemical precipitation method at room temperature. The effects of surfactants on the structural and optical properties of nanoparticles are characterized. The optical properties of the nanoparticles were investigated by UV–visible and PL spectroscopy. The effects of surfactants with observed band shifts are due to quantum confinement effect. The optical band gap values are determined by simple energy wave equation and Tauc plot method. The observed particle sizes are very closer to the Bohr exitonic radius. The emission bands such as violet, blue, green and orange are observed in PL spectra. The PL integrated intensity ratio of the UV emission to the deep-level green emission ( I UV / I DLE ) for CTAB, PEG and SDS capped CeO 2 nanoparticles are observed. The XRD measurement shows that CeO 2 has cubic fluorite structure having the particle size 6–10 nm. The lattice strains were detected by Williamson–Hall plot method. The surface morphology of the nanoparticles is studied by SEM and FESEM analysis. TEM images show that the particles are nearly spherical in shape with diameter of 5–10 nm. Using FTIR spectra, the functional groups of the ceria are identified. [ABSTRACT FROM AUTHOR]

Abstract: Synthesis and hardening of a new exoskeleton are essential to the arthropod molting process. The present study emphasizes the variations in the levels of hemolymph total free sugars, hepatopancreas glycogen and cuticular proteins during the molting stages of Portunus pelagicus. It also reports the effect of short-term starvation conditions on the biochemical constituents of the hemolymph. Intermolt crabs were subjected to 6days of starvation and hemolymph samples were taken. Standard biochemical procedures were followed toward the quantification of total proteins, total free sugars and total lipids. The total free sugar level in the hemolymph of P. pelagicus was observed to increase during early premolt D0 (3.108±0.032g/ml) and a gradual decrease till late postmolt B stage (0.552±0.124g/ml), suggesting the need for total free sugars to provide energy for the apolysis process. Increase in the levels of hepatopancreas glycogen was observed from 1225±0.04μg/mg in early premolt D0 to 1700±0.3μg/mg in late premolt D2–3. This is in correlation with the decreased levels of free sugars during premolt stages, suggesting an increase in the storage of glycogen reserves in the hepatopancreas. Cuticular proteins increased during stage B (2.702±0.093g/ml) and stage C (3.065±0.012g/ml), indicating exoskeleton hardening and mineralization. Results of the starvation studies clearly showed a steady decline in the level of total free sugars till day 6 (0.099±0.00g/ml) when compared to the control (8.646±0.08g/ml). Gradual decrease of total lipids was also observed from the first day of the experiment (6.088±2.44g/ml) to the last day of the study (0.401±0.20g/ml) which was 85% lesser than the control (8.450±0.49g/ml)suggesting the efficient usage of total sugars to consolidate the loss of energy reserves during starvation. The knowledge of Molt-cycle events can be used as a tool for the evaluation of the developmental state providing a morphological reference system for physiological and biochemical studies related to crab aquaculture. Starvation studies enlightens that increasing carbohydrate levels in crab feed together with good protein content could alleviate the natural effects of starvation, improve farm productivity and reduce the deleterious impact of nitrogen pollution generated by rich-protein feeds used in crab farming. [Copyright &y& Elsevier]

Efficacy of nanoparticle is essentially influenced by the medium in which it is dispersed, the size of the particles in dispersion and the stability of dispersion. The major constrain in dealing with nanoparticle dispersion can be resolved by identifying a proper dispersive medium. In the present study, dispersions of zinc oxide and copper oxide nanoparticles was prepared in propylene glycol (PG). Dynamic light scattering analysis showed that particles remained in nano size without formation of aggregates. UV-vis. absorption spectroscopy showed that the nano-dispersion in propylene glycol is stable without adding any additional surfactants or dispersive agents. Fungal decay and moisture adsorption of rubberwood ( Hevea brasiliensis Muell Arg. ) specimens impregnated with nano-ZnO and nano-CuO dispersion in PG was evaluated. Dispersion of ZnO and CuO nanoparticles in PG inhibited white-rot ( Trametes hirsuta ) and brown-rot ( Polyporus meliae ) decay effectively. The changes observed in FTIR spectra and SEM further support the results. Nano-dispersions treated specimens showed some reduction in moisture adsorption with lower equilibrium moisture content values as compared to untreated wood. [ABSTRACT FROM AUTHOR]

Over the millennia, mankind has recognized the inherent resistance of certain wood species against attack by fungi, insects and marine borers. Despite our advances in wood protection technology, people still rely on naturally durable timbers for construction of various structures. Of late, this property of several wood species, known for their high durability, has become unreliable due to changes in silvicultural and pre-harvesting practices, which reportedly interfere with their durability performance. This warrants a periodic assessment and rating of natural durability properties to select the right species for various end uses. Moreover, the drastic decline in the availability of naturally durable timber species towards the end of 20th century has resulted in the import/export of timber world-wide. The inherent durability of these species under different climatic conditions is unknown but must be determined to utilize them effectively. Studies on natural resistance of wood to biological damage are therefore of prime importance. Before initiating durability studies, background information on different factors that impart durability to a timber is vital. This paper aims to compile secondary data on such aspects and to provide a necessary check-list of durability ratings of Indian and exotic timbers that have been tested under Indian environmental conditions. Probable factors responsible for imparting a built-in resistance to wood against bio-deterioration have also been discussed. [ABSTRACT FROM AUTHOR]

Abstract: A mutant Aspergillus carbonarius produces partially saturated canthaxanthin (PSC; C40H62O2) during submerged fermentation. The pigment was extracted from dried biomass using various organic solvents and purified using nanofiltration (NF) and nonporous membranes. Particle size had a great influence; PSC extractability from fines fraction of biomass (75–105μm) was 1.5-fold higher compared to the coarse fraction (850–920μm) in ethanol. Among the four solvents, hexane exhibited the highest PSC extractability of 5.83mg/g and purity of 32mg/g. On a relative scale, the extraction performance of hexane, acetone, methanol and ethanol were in the order 100, 16.1, 7.5 and 5.4. An assessment based on enrichment factor and permeate flux revealed notable performance with NF-250 membrane in ethanol extract followed by NF-200 and NF-GKSS membranes in methanol extract. These results suggested the suitability of hexane for extraction followed by alcohol phase purification and concentration employing NF. Accordingly, a PSC purity of 206mg/g was achieved. [Copyright &y& Elsevier]

Abstract: Monascus purpureus MTCC 410-fermented rice (red mould rice) is one of the food supplements to lower blood–lipid levels and monacolins have been proven to be the main active constituents in red mould rice (RMR). In this study, we have assessed the safety of RMR by conducting toxicological studies in albino rats. Acute and sub-chronic toxicity studies were conducted on both sexes of albino rats. Feeding acute doses of RMR at 0.5, 1.0, 2.5 and 5.0g/kg body weight to rats did not cause any symptoms of toxicity or mortality. Similarly, dietary feeding of RMR at 2.0%, 4.0%, 8.0% and 12.0% level (w/w) for 14weeks did not produce any significant changes in food intake or gain in body weight of the experimental rats compared to control rats. There were no significant differences in the relative weight of vital organs, hematological parameters, macroscopic and microscopic changes in vital organs and serum clinical enzyme levels between the experimental and control groups. Moreover, the rats fed with RMR showed a significant reduction in cholesterol and triglyceride levels in both serum and liver. The results showed that toxicity studies with RMR of M. purpureus did not cause any toxic effects in albino rats. [Copyright &y& Elsevier]

Abstract: Aspergillus carbonarius, an ascomycetes fungus, is known to produce pectinase in solid-state fermentation. A mutant strain of A. carbonarius UV-10046 selected for temperature tolerance over produced polygalacturonase and during growth accumulated an yellow pigment in its biomass. Since the colored fungus suggested its application for food use, the freeze-dried biomass was evaluated to assess its safety in experimental animals. Acute and sub-acute toxicity studies were conducted on both sexes of albino rats. Feeding acute doses of A. carbonarius freeze-dried biomass at 0.5–5.0g/kg body weight to adult rats did not show any symptoms of toxicity or mortality of the rats. Similarly, dietary feeding of A. carbonarius at 0.25–2.0% level (w/w) for 14 weeks did not produce any significant changes in food intake or gain in body weight of the experimental rats compared to control rats. There were no significant differences in the relative weight of vital organs, hematological parameters, macroscopic and microscopic changes in vital organs and serum enzyme levels between the experimental and control groups. The results clearly showed that acute and sub-acute oral feeding of freeze-dried whole cells of A. carbonarius mutant for 14 weeks did not produce any toxic effects in male and female rats. [Copyright &y& Elsevier]