Evaluation of nutritional and nutraceutical potentials of three wild edible mushrooms from Similipal Biosphere Reserve,Odisha, India

A variety of edible mushrooms are growing in Similipal Biosphere Reserve (SBR), some of which are used as ethno-medicine by indigenous tribals. In the present study, three wild edible mushrooms viz., Russula vesca, Russula delica and Termitomyces eurrhizus of SBR were analyzed for their nutritional and mineral contents along with antioxidant and antibacterial potential. The results showed that these three mushrooms are rich sources of nutrients (protein, carbohydrate, starch, reducing sugars and low fats), micronutrients (vitamins and carotenoids) and minerals (P, K, Mn, Co, Ni, Cd, Fe) with promising bioactive properties (antioxidant and antibacterial potentials). In general, these mushrooms revealed high amounts of proteins (22.82–35.17 g/100 g) and carbohydrates (45.68–63.27 g/100 g) and low contents in fats (2.03–4.62 g/100 g), while micronutrients (vitamins and carotenoids) and minerals were present in significant amounts. The antioxidant potentials of three different solvent extracts (ethanol, methanol and aqueous) of studied wild mushrooms showed strong antioxidant properties (ABTS, DPPH, H₂O₂ and metal chelating activities) with scavenging potential up to 89 % at concentration 100 μg/ml. Total phenol content was found between 21.92–41.99 mg catechol/g extract and flavonoid 2.53–7.52 mg quercetin/g extract. The studied mushrooms possess moderate antibacterial properties with zones of inhibition ranging from 13 to 30 mm against six human pathogenic bacteria which are comparable with Amphoxyllin standard. Being a source of nutrients and molecules with medicinal potential, the studied mushrooms can be used in human diet as nutraceuticals/functional foods for maintaining and promoting health, longevity and life quality.     

Anisotropic Magnetocaloric Effect in Single-crystalline Pr0.52Sr0.48MnO3

We report the magnetocaloric effect (MCE) in a Pr_0.52Sr_0.48MnO₃ single crystal estimated from the isothermal magnetization curve using the Maxwell relation. Isothermal magnetization curves are measured over the range 20 K to 320 K where the field was applied parallel (??) and perpendicular (??) to the [110] direction of the perovskite structure with Pbnm space group. A peak in the temperature (T) dependence of magnetic entropy change (??S _M) with a fairly large negative value (???3.3 J/kg?K) is observed at 275 K close to the Curie temperature (T _C) for a change in field of ??H=40 kOe. The ?? and ?? components of ??S _M deviate from each other below ??260 K and an inverse MCE is observed below ??150 K. We note that the Landau theory of phase transitions satisfactorily explains the ??S _M vs T plot around the second-order transition at T _C.     

Synthesis,characterization, and properties of flexible magnetic nanocomposites of cobalt ferrite–polybenzoxazine–linear low‐density polyethylene

A simple method for the preparation of magnetic nanocomposites consisting of cobalt ferrite (CF; CoFe₂O₄) nanoparticles, polybenzoxazine (PB), linear low‐density polyethylene (LLDPE), and linear low‐density polyethylene‐g‐maleic anhydride (LgM) is described. The composites were prepared by the formation of benzoxazine (BA)–CF nanopowders followed by melt blending with LLDPE and the thermal curing of BA. The composites were characterized by X‐ray diffraction, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, universal testing machine measurement, and vibrating sample magnetometry. The composites consisting of LLDPE, PB, and LgM (47.5L–47.5PB–5LgM) exhibited a higher tensile strength (23.82 MPa) than pure LLDPE and a greater elongation at break (6.11%) than pure PB. The tensile strength of the composites decreased from 19.92 to 18.55 MPa with increasing CF loading (from 14.25 to 33.25 wt %). The saturation magnetization of the composites containing 33.25 wt % CF was 18.28 emu/g, and it decreased with decreasing amount of CF in the composite. The composite films exhibited mechanical flexibility and magnetic properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Foam‐Like Behavior in Compliant,Continuously Reinforced Nanocomposites

In the pursuit of advanced polymer composites, nanoscale fillers have long been championed as promising candidates for structural reinforcement. Despite progress, questions remain as to how these diminutive fillers influence the distribution of stresses within the matrix and, in turn, influence bulk mechanical properties. The dynamic mechanical behavior of elastomer‐impregnated forests of carbon nanotubes (CNTs) has revealed distinct orientation‐dependent behavior that sheds light on these complicated interactions. When compressed along the axis of the fillers, the composite will mimic open‐cell foams and exhibit strain softening for increasing amplitudes due to the collective Euler buckling of the slender nanotubes. In contrast, the same material will behave similarly to the neat polymer when compressed orthogonal to the alignment direction of the nanotubes. However, in this orientation the material is incapable of achieving the same ultimate compressive strain due to the role that the embedded nanotubes play in augmenting the effective cross‐link density of the polymer network. Both of these responses are recoverable, robust, and show little dependency on the diameter and wall‐number of the included CNTs. Such observations give insight into the mechanics of polymer/nanoparticle interactions in nanocomposite structures under strain, and the thoughtful control of such coordinated buckling behavior opens the possibility for the development of foam‐like materials with large Poisson ratios.     

KMnO4 pre-treatment of linen

Currently, for the textile industry, the economical considerations are of great importance. The concept of eco-friendliness is of greater concern for textile processing, as the chemical wet treatment has a major role in effluent generation. Thus, research activities these days are oriented towards the alternative ways of chemical processing. Potassium permanganate, a strong oxidising agent can be employed for the pre-treatment of grey linen. The experimental investigation reveals that the KMnO₄ concentration, temperature and treatment time have noticeable impact on quality of bleached linen. The results are evaluated in terms of whiteness index and strength of fabric and the treatment factors are optimised using design of experiment. The results demonstrate that the KMnO₄ can be employed for simultaneous desizing and bleaching of grey linen.     

A fast automatic optimal threshold selection technique for image segmentation

In this article, a fast context-sensitive threshold selection technique is presented to solve the image segmentation problems. In lieu of histogram, the proposed technique employs recently defined energy curve of the image. First, the initial thresholds are selected in the middle of two consecutive peaks on the energy curve. Then based on the cluster validity measure, the optimal number of potential thresholds and the bounds where the optimal value of each potential threshold may exist are determined. Finally, genetic algorithm (GA) is employed to detect the optimal value of each potential threshold from their respective defined bounds. The proposed technique incorporates spatial contextual information of the image in threshold selection process without loosing the benefits of histogram-based techniques. Computationally it is very efficient. Moreover, it is able to determine the optimal number of segments in the input image. To assess the effectiveness of the proposed technique, the results obtained are compared with four state-of-the-art methods cited in the literature. Experimental results on large number of images confirmed the effectiveness of the proposed technique.     

Ruthenium(II) Complex-Based G-quadruplex DNA Selective Luminescent ‘Light-up’ Probe for RNase H Activity Detection

A bis-heteroleptic ruthenium(II) complex, 1[PF₆]₂ of benzothiazole amide substituted 2,2′-bipyridine ligand ( bmbbipy ) has been synthesized for the selective detection of G-quadruplex (GQ) DNA and luminescence-assay-based RNase H activity monitoring. Compound 1[PF₆]₂ exhibited aggregation-caused quenching (ACQ) in water. Aggregate formation was supported by DLS, UV-vis, and ¹H NMR spectroscopy results, and the morphology of aggregated particles was witnessed by SEM and TEM. 1[PF₆]₂ acted as an efficient GQ DNA-selective luminescent light-up probe over single-stranded and double-stranded DNA. The competency of 1[PF₆]₂ for selective GQ structure detection was established by PL and CD spectroscopy. For 1[PF₆]₂ , the PL light-up is exclusively due to the rigidification of the benzothiazole amide side arm in the presence of GQ-DNA. The interaction between the probe and GQ-DNA was analyzed by molecular docking analysis. The GQ structure detection capability of 1[PF₆]₂ was further applied in the luminescent ‘off-on’ RNase H activity detection. The assay utilized an RNA:DNA hybrid, obtained from 22AG2-RNA and 22AG2-DNA sequences. RNase H solely hydrolyzed the RNA of the RNA:DNA duplex and released G-rich 22AG2-DNA, which was detected via the PL enhancement of 1[PF₆]₂ . The selectivity of RNase H activity detection over various other restriction enzymes was also demonstrated.     

Eco-efficient Separation of Mono- and Dichloroacetic Acid by Thermally Coupled Extractive Distillation

Due to its high reactivity, monochloroacetic acid (MCA) is an essential intermediate used in the manufacturing of a wide variety of chemicals. Its industrial production process is highly energy- and capital-intensive, requiring costly purification steps to remove dichloroacetic acid (DCA) impurities. Here, an innovative eco-efficient process for MCA-DCA separation is proposed based on extractive distillation in a fully thermally coupled system (a dividing-wall column (DWC) or an equivalent side-rectifier configuration) using a new effective solvent: diethylene glycol dipentylether. The design was optimized by performing sensitivity analyses and varying key operating and design parameters. The study proves that separating MCA-DCA by an extractive DWC (or thermally coupled) is feasible, efficient, controllable, economic, and sustainable.