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[Display omitted] • Tasar food plants affect the chemical nature of sericin. • Higher C: N ratio and phenolic content was observed in Shorea robusta sericin. • Higher aromatic and hydrophobic amino acids were also detected in S. robusta sericin. • S. robusta sericin shows higher antioxidant potential and enzymatic inhibition. Sericin were isolated and characterized from tasar cocoons raised in three different food plants i.e. Terminalia arjuna, T. tomentosa and Shorea robusta for its applications. Their molecular composition, structure and physical nature were determined by elemental analysis, amino acid analysis, Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) analysis. These results show that tasar food plants influence the physical and chemical properties of sericin. Further, sericin isolated from cocoons of S. robusta food plant shows better antioxidant potential and inhibition of tyrosinase, elastase and glutathione-S-transferase activity than other food plants. This may be attributed to its amino acid variations and associated phenolic content. The present study appears to be useful in utilizing tasar sericin as a potential bio-molecule for its prospective utilization in pharmaceuticals and its associated fields. [ABSTRACT FROM AUTHOR]

Abstract: The detection of nucleic acid bases in carbonaceous meteorites suggests that their formation and survival is possible outside of the Earth. Small N-heterocycles, including pyrimidine, purines and nucleobases, have been extensively sought in the interstellar medium. It has been suggested theoretically that reactions between some interstellar molecules may lead to the formation of cytosine, uracil and thymine though these processes involve significantly high potential barriers. We attempted therefore to use quantum chemical techniques to explore if cytosine can possibly form in the interstellar space by radical–radical and radical-molecule interaction schemes, both in the gas phase and in the grains, through barrier-less or low barrier pathways. Results of DFT calculations for the formation of cytosine starting from some of the simple molecules and radicals detected in the interstellar space are being reported. Global and local descriptors such as molecular hardness, softness and electrophilicity, and condensed Fukui functions and local philicity indices were used to understand the mechanistic aspects of chemical reaction. The presence and nature of weak bonds in the molecules and transition states formed during the reaction process have been ascertained using Bader’s quantum theory of atoms in molecules (QTAIMs). Two exothermic reaction pathways starting from propynylidyne (CCCH) and cyanoacetylene (HCCCN), respectively, have been identified. While the first reaction path is found to be totally exothermic, it involves a barrier of 12.5kcal/mol in the gas phase against the lowest value of about 32kcal/mol reported in the literature. The second path is both exothermic and barrier-less. The later has, therefore, a greater probability of occurrence in the cold interstellar clouds (10–50K). [Copyright &y& Elsevier]

Abstract: Experimental methods of infrared, Raman and electronic absorption spectroscopy and DFT calculations using B3LYP functionals and 6-31G** and 6-311++G** basis sets have been used to understand the structural and spectral characteristics of 2-pyranones, 6-phenyl-4-methylsulfanyl-2-oxo-2H-pyran and 6-phenyl-4-methylsulfanyl-2-oxo-2H-pyran-3-carbonitrile in the electronic ground (S0) and first excited (S1) states. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecules has been obtained by mapping electron density isosurface with electrostatic potential surfaces (ESP). Based on TD-DFT calculations using 6-31+G**5D basis set, an assignment of absorption peaks in the UV–VIS region has been suggested. The S1 state is found to be a 1(π,π*) state. A complete vibrational analysis has been attempted on the basis of experimental infrared and Raman spectra and calculated frequency and intensity of the vibrational bands and potential energy distribution over the internal coordinates. Characteristic vibrational bands of the 2-pyranone ring and methylsulfanyl and carbonyl groups have been identified. [Copyright &y& Elsevier]

Rotational isomerism in methyl trans crotonate (MC) and its properties in the ground (S0) and first excited (S1) electronic states have been studied by spectroscopic and quantum chemical techniques such as Density Functional Theory (DFT) with B3LYP functionals and RHF using extended basis sets like 6-31G, 6-31G*, 6-31G** and 6-311+G**. Electron correlational corrections at Moller–Plesset MP2 level have been included in RHF calculations. The molecule was treated as a two-rotor system with the additional possibility of hindered rotation of the methyl group about C–O bond. Conformations in which the carbonyl and methoxy groups are in cis position are found to be most stable with the methyl group having staggered conformation relative to the carbonyl group. Plot of potential energy curves in the S0 and S1 states by RHF /6-31G based calculations indicates in each case the presence of two stable rotameric conformations, Cc and Tc separated by 0.645 and 1.653 kcal/mol, respectively. The former, in which the C&z.dbnd6;C and C&z.dbnd6;O bonds are in cis positions, is more stable than the latter, in which these bonds are in trans position. Electronic excitation is found to substantially reduce rotational barrier between the two conformers, making their inter-conversion in the S1 state easier. Fully optimized geometries of the two stable conformers in the S0 and S1 states are being reported by RHF/ 6-31G** and RHF/6-311+G** basis sets. Based on suitably scaled RHF/ 6-31G** and DFT/6-311G** calculations, assignments have been provided to the fundamental vibrational bands of both the Cc and Tc conformers in terms of frequency, form and intensity of vibrations and potential energy distribution across the symmetry coordinates in the S0 state. A complete interpretation of the electronic spectra of Cc and Tc conformers of MC in terms of nature, energy and intensity of electronic transitions has been provided on the basis of configuration interaction level calculations. [Copyright &y& Elsevier]

A systematic quantum mechanical study of the possible conformations, their relative stabilities, vibrational and electronic spectra and thermodynamic parameters of methyl methacrylate (MMA) has been reported for the electronic ground (S0) and first excited (S1) states using Density Functional Theory (DFT) with B3LYP functionals and RHF methods in extended basis sets 6-31G, 6-31G**, 6-311G** and 6-311+G** have been conducted. The molecule was considered as a two rotor system having internal rotation about C–C and C–O bonds with the possibility of hindered rotation of the methyl group. Rotation about C–O bond indicates that conformations having the carbonyl and methoxy groups in cis positions are the most stable, while the methyl group has staggered conformation relative to the carbonyl group. Plots of the potential energy curves for rotation about C–C bonds in the S0 and S1 states show two energy minima corresponding to the Tc and Cc conformations, separated by 0.365 and 1.104 kcal/mol, respectively, and indicate that the former is more stable than later in both the electronic states. Electronic excitation is found to substantially reduce rotation barrier between the two conformers, which may make their inter-conversion in the S1 state easier. Fully optimized geometries of the two stable conformers in the S0 and S1 states are being reported; the later being reported for the first time. Based on suitably scaled RHF/6-31G** and DFT/6-311G** results, a complete assignment is provided to the fundamental vibrational bands of both the Tc and Cc conformers in terms of frequency, form and intensity of vibrations and potential energy distribution across the symmetry coordinates in the S0 state. A complete interpretation of the electronic spectra of the Tc and Cc conformers of MMA has been provided by MP2/6-31G** calculations in terms of the nature, energy and intensity of electronic transitions. [Copyright &y& Elsevier]

Abstract Tropical tasar silkworm Antheraea mylitta is a wild sericigenous insect which is distributed in different geographical regions and named as different ecoraces. In the present study, we investigated the molecular characterisation and cosmeceutical properties of sericin extracted from different ecoraces of tasar cocoons. The surface morphology and molecular weight of cocoons were determined by scanning electron microscope (SEM) and SDS-PAGE, respectively. Characterisation of sericin was performed by various methods such as FTIR, CHNS, TGA and amino acid analyzer. The anti-tyrosinase, anti-elastase, glutathione-S-transferase inhibition, free radical scavenging potential and inhibition of oxidative damages were measured in tasar ecoraces sericin. SEM images have revealed the removal of sericin from the surface of cocoons. SDS-PAGE of sericin depicted the presence of diverse molecular weight of proteins. Structural determination by FTIR revealed the presence of both α-helical and β-sheet structures. Thermal properties of sericin were studied by TGA which showed a 50% weight loss at temperature 410 °C–430 °C. Additionally, ecoraces sericin contains 17 amino acids in which serine, aspartic acid and glycine are predominantly present (55.68–59.61%). Further, anti-tyrosinase, anti-elastase, inhibition of glutathione-S-transferase activity, free radical scavenging potential and inhibition of lipid peroxidation were also observed in ecoraces sericin. Our findings suggest that the present study appear to be helpful in exploiting sericin as potential biomaterial in cosmeceutical and allied field. Highlights • Tasar sericin (TS) having different physical and chemical natures • TS exhibits free radical scavenging properties. • TS shows inhibition of tyrosinase and elastase activities. • TS suppresses lipid peroxidation and GST activity. [ABSTRACT FROM AUTHOR]

The present study investigates the properties of sericin extracted from tasar silk fiber waste (TSFW). The surface morphology of TSFW was observed by scanning electron microscope (SEM). SEM images revealed the removal of residual sericin over the surface of TSFW. The molecular weight distribution of sericin was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results suggested that TSFW sericin represented a family of proteins with wide-ranging molecular weight distribution (11–245 kDa). Structural determination by FTIR revealed the presence of both α-helical and β-sheet structures. The colour was studied by colorimeter indicating less brightness, more red and yellow colour intensities. The carbon: nitrogen ratio (C:N) was studied by CHNS element analyzer and the ratio is 5.15-7.85. Thermal properties of TSFW sericin have been studied by thermogravimetric analysis (TGA) method. TGA curve showed higher thermal stability and variable degradation profiles. Furthermore, TSFW sericin contains 17 amino acids where serine, aspartic acid and glycine are the more significant compounds (54.34–60.49%). In addition, sericin was found to inhibit tyrosinase, elastase and glutathione-S-transferase activity, and had apparent radical scavenging impacts on 2.2‑diphenyl‑1‑picryl‑hydrazil (DPPH), hydrogen peroxide and inhibition of lipid peroxidation. Result suggested that TSFW sericins might be a valuable ingredient for cosmoceutical products. [ABSTRACT FROM AUTHOR]

In the present paper, structural and electrical properties of 2% Fe doped molybdenum oxide thin films grown by the pulsed laser deposition (PLD) technique have been reported. Ion beam induced modifications of these films were studied under the bombardment of 100 MeV Ni 8+ ions. X-ray diffraction (XRD), Fourier transform infrared spectroscopy, and micro-Raman measurements suggested the formation of mainly orthorhombic (α-phase) MoO 3 in the films along with the presence of monoclinic (β-phase) MoO 3 and MoO 2 . Ion bombardment induced structural disorder in the MoO 3 films. Room temperature resistivity of the as-grown film was 13.85 Ω-cm. The resistivity increased with increasing ion fluence ( ϕ ), and the values were found to be 47.6 Ω-cm, 73.7 Ω-cm, and 101.6 Ω-cm for ϕ =1×10 12 , 1×10 13 , and 1×10 14 ions-cm −2 , respectively. [ABSTRACT FROM AUTHOR]

We report structural, magnetic and electronic structural properties of Ni doped ZnO nanoparticles prepared by auto-combustion method. The prepared nanoparticles were characterized by using X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), near edge X-ray absorption fine structure (NEXAFS) spectroscopy, and dc magnetization measurements. The XRD and HR-TEM results indicate that Ni doped ZnO nanoparticles have single phase nature with wurtzite lattice and exclude the presence of secondary phase. NEXAFS measurements performed at Ni L 3,2 -edges indicates that Ni ions are in +2 valence state and exclude the presence of Ni metal clusters. O K -edge NEXAFS spectra indicate an increase in oxygen vacancies with Ni-doping, while Zn L 3,2 -edge show the absence of Zn-vacancies. The magnetization measurements performed at room temperature shows that pure and Ni doped ZnO exhibits ferromagnetic behavior. [ABSTRACT FROM AUTHOR]

Abstract: A concise and convenient synthesis of various partially reduced 6-sec-amino-1,2,3,4,7,8-hexahydro-, 6-sec-amino-1,2,7,8-tetrahydrobenzo[c]phenanthrene-5-carbonitriles, 6-sec-amino-3,4,7,8-tetrahydro-1H-benzo[c]phenanthrene-2-one-5-carbonitrile cycloalkene ketals, pendant with electron donor and acceptor substituents has been described through base catalyzed ring transformation of 2-oxo-4-sec-amino-5,6-dihydro-2H-benzo[h]chromene-3-carbonitriles by cyclohexanone, 2-cyclohexen-1-one, 1,4-cyclohexanedione monocycloalkene ketals. The acid catalyzed deketalation of 6-sec-amino-3,4,7,8-tetrahydro-1H-benzo[c]phenanthrene-2-one-carbonitrile ketals led to yield 6-sec-amino-3,4,7,8-tetrahydro-1H-benzo[c]phenanthrene-3-carbonitrile-2-ones in excellent yield. We also performed the X-ray studies of the molecules 3d and 6a to know the degree of non-planarity. [Copyright &y& Elsevier]

Abstract: Objective: There is a wide disparity in prevalence and cardiovascular disease mortality in different Indian states. To determine significance of various nutritional factors and other lifestyle variables in explaining this difference in cardiovascular disease mortality we performed an analysis. Methods and results: Mortality data were obtained from the Registrar General of India. In 1998 the annual death rate for India was 840/100,000 population. Cardiovascular diseases contribute to 27% of these deaths and its crude mortality rate was 227/100,000. Major differences in cardiovascular disease mortality rates in different Indian states were reported varying from 75–100 in sub-Himalayan states of Nagaland, Meghalaya, Himachal Pradesh and Sikkim to a high of 360–430 in Andhra Pradesh, Tamil Nadu, Punjab and Goa. Lifestyle data were obtained from national surveys conducted by the government of India. The second National Family Health Survey (26 states, 92,447 households, 301,984 adults) conducted in 1998–1999 reported on various demographic and lifestyle variables and India Nutrition Profile Study reported dietary intake of 177,841 adults (18 states, 75,229 men, 102,612 women). Cardiovascular disease mortality rates were correlated with smoking, literacy levels, prevalence of stunted growth at 3-years (as marker of fetal undernutrition), adult mean body mass index, prevalence of overweight and obesity, dietary consumption of calories, cereals and pulses, green leafy vegetables, roots, tubers and other vegetables, milk and milk products, fats and oils, and sugar and jaggery. As a major confounder in different states is poverty, all the partial correlation coefficients were adjusted for illiteracy, fertility rate and infant mortality rate. There was a significant positive correlation of cardiovascular disease mortality with prevalence of obesity (R =0.37) and dietary consumption of fats (R =0.67), milk and its products (R =0.27) and sugars (R =0.51) and negative correlation with green leafy vegetable intake (R =−0.42) (p <0.05). Conclusions: There are large disparities in cardiovascular disease mortality in different Indian states. This can be epidemiologically explained by difference in dietary consumption of fats, milk, sugar and green-leafy vegetables and prevalence of obesity. [Copyright &y& Elsevier]

Objective: Epidemiological study among urban subjects in western India to determine prevalence of diabetes, insulin resistance syndrome (IRS) and their risk factors. Methods: Randomly selected adults ≥20 years were studied using stratified sampling. Target sample was 1800 (men 960, women 840). 1123 subjects (response 62.4%) were evaluated and blood samples were available in 532 men and 559 women (n=1091, 60.6%). Measurement of anthropometric variables, blood pressure, fasting blood glucose and lipids was performed. Atherosclerosis risk factors were determined using current guidelines. Diabetes was diagnosed when the subject was a known diabetic or fasting blood glucose was ≥126 mg/dl, impaired fasting glucose (IFG) diagnosed when fasting glucose was 110–125 mg/dl. IRS was diagnosed when any three of–IFG, high triglycerides >150 mg/dl, low HDL cholesterol (men<40 mg/dl, women<50 mg/dl), central obesity (men>102 cm, women>88 cm), or high normal blood pressure (>130/>85 mmHg) or hypertension-were present. Results: Diabetes was present in 70 men (13.2%) and 64 women (11.5%). Age-adjusted prevalence of diabetes was 9.3% in men (95% confidence intervals (CI) 6.7–11.8), 8.1% in women (CI 5.8–10.4) and 8.6% overall (CI 6.9–10.3). IFG was in 28 men (5.3%) and 29 women (5.2%). IRS was present in 52 men (9.8%) and 114 women (20.4%) with age-adjusted prevalence of 7.9% in men (CI 6.7–9.1) and 17.5% in women (CI 14.4–20.6) with an overall prevalence of 12.8% (CI 10.8–14.8). Other metabolic abnormalities of IRS in men and women were high triglycerides in 32.1 and 28.6%, low HDL cholesterol in 54.9 and 90.2%; central obesity in 21.8 and 44.0%, and high normal blood pressure or hypertension in 35.5 and 32.4%. IFG subjects had similar atherosclerosis risk factor profile as normal subjects while those with IRS and diabetes had significantly greater prevalence of obesity, central obesity, hypertension, high triglycerides and low HDL (P<0.01). Conclusions: There is s significant prevalence of diabetes and IRS in this urban Indian population. Subjects with diabetes as well as IRS have greater prevalence of obesity, central obesity, hypertension, hypertriglyceridemia and low HDL as compared with normal subjects. [Copyright &y& Elsevier]

Abstract: Congenital ectropion uveae (CEU) is a rare, non progressive anomaly characterised by the presence of iris pigment epithelium on the anterior surface and is frequently associated with anterior iris insertion, dysgenesis of the drainage angle and glaucoma. This paper describes an unusual case of bilateral congenital ectropion uveae with iris coloboma and telecanthus. The anterior chamber angle was normal and there was no evidence of glaucoma. To the best of our knowledge, this association has not been reported previously. [Copyright &y& Elsevier]