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Centella asiatica (L.) Urban (Apiaceae) possesses various healing effects and antioxidant properties. However, there has been very less focus on the investigation of chemotypic variations of C. asiatica found in different geographical zones of the country. In order to conserve C. asiatica, as it is an industrially valuable herb and overexploitation of this drug from wild is a common practice, different distinct accessions of C. asiatica from Nilgiri range (Deccan zones) of India were compared in relation to the levels of triterpenoid saponins. Physicochemical parameters were also evaluated in all the accessions. The metabolites investigated include madecassoside, asiaticoside, and its sapogenin, asiatic acid by high-performance thin-layer chromatography (HPTLC). CA-45 showed the highest content of asiaticoside, CA-51 showed the highest content of madecassoside, and CA-47 showed the highest content of asiatic acid among other accessions of Nilgiri range. It can be concluded that the geographical conditions (soil type and altitude) of these accessions are comparatively favorable for the production of higher levels of triterpenoid saponins in C. asiatica. The reported data will contribute to the establishment of knowledge about the triterpenoid saponin composition of different chemotypes of C. asiatica found in Nilgiri range of India in comparison to other geographical areas, and lays a foundation for the conservation and commercial cultivation of this plant.

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Abstract

The kinetics of the decolorization reaction of methyl violet dye (MV) with the hydroxyl ion (nucleophile) was studied in the presence of cationic micelles of cetyltrimethylammonium bromide (CTAB). The reaction follows pseudo-first order kinetics. The rate constant depends on the surfactant concentration. CTAB micelles catalyze the overall reaction between the dye carbocation and the nucleophile. Quantitative analysis of the micellar data obtained has been done by applying positive cooperativity model of enzyme catalysis. For the dye under study, the value of n (index of cooperativity) has been found to be greater than 1. The catalytic effect has been explained in terms of hydrophobic and electrostatic interactions of various species present in the reaction systems. The addition of a counterion showed inhibitory effect on the reaction.

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Zinc is essentially required for crop growth and its insufficient supply to the plants may severely limit the yield traits of a crop. A field experiment was performed during rabi season of 2009–10 and 2010–11 to evaluate the performance of different wheat genotypes under different levels of zinc namely 0 kg ZnSO4 ha−1, 20 kg ZnSO4 ha−1 and 20 kg ZnSO4 ha−1 along with foliar spray of 0.5% solution of ZnSO4. Genotypes responded positively in terms of tiller number, grain and biological yield, spikelet length, spikelet number, grain number and thousandgrain weight. The best response was observed with the application of 20 kg ZnSO4 ha−1 along with foliar spray of 0.5% solution of ZnSO4. Zinc application brought about a maximum increase of 58.6% in tiller number, 63.7% in thousand-grain weight, 40.5% in biological yield, 66.1% in grain yield irrespective of genotypes and the year of study. Wheat genotypes exhibited a variation in their performance which has been exploited in this study. Genotypes UP-262, PBW-175, PBW-343 were found to be superior for one or the other yield contributing factors.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
S. Ermolaev
,
B. Zhuikov
,
V. Kokhanyuk
,
A. Abramov
,
N. Togaeva
,
S. Khamianov
, and
S. Srivastava

Abstract  

A method for production of no-carrier-added 117mSn (NCA 117mSn) has been developed. It includes proton irradiation of thick antimony targets and chemical recovery of 117mSn by extraction of Sb with dibutyl ether and chromatographic purification on silica gel column. The method provides production of curie amounts of 117mSn with specific activity about 1000 Ci/g and high radionuclidic purity.

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Acta Agronomica Hungarica
Authors:
S. P. Saikia
,
S. P. Saikia
,
V. Jain
,
V. Jain
,
G. C. Srivastava
, and
G. C. Srivastava

Research over the last few years has shown that inoculation with nitrogen-fixing bacteria of the genus Azorhizobium presents an alternative for (or supplement to) chemical fertilization, mainly due to the capability of the bacteria to produce plant growth- promoting hormones. The Azorhizobium caulinodans strain ORS 571 in combination with 2,4-D was able to colonize the root interior of an Indian maize cultivar. After transplanting to pots, it was noticed that nodulated and Azorhizobium -treated plants showed higher chlorophyll content in the leaf and enhanced nitrate reductase activity, leading to higher yield as compared to the control plants (non-nodulated). A plant growth-promoting effect was clearly visible in all inoculated plants examined. nodulated plants treated with Azorhizobium had higher physiological activities as compared to plants treated only with Azorhizobium . Azorhizobium therefore creates potentially better symbiosis in the form of para -nodules and promotes a higher level of nitrogen fixation, leading to better growth and plant development, with reduced requirements for chemical fertilizers.

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Summary  

Germanium-68 is produced at the Brookhaven Linac Isotope Producer (BLIP) by irradiating natGa targets with ~45 MeV protons. Typical irradiation yields are 17.4 GBq (470 mCi) from a 4 week irradiation (0.52 MBq/µAh). Germanium-68 is recovered from the target by extraction into 4N HCl and 30% H2O2. Further purification is achieved by extraction into carbon tetrachloride and back-extraction into H2O. Recovery yields are greater than 85%, with greater than 99% radiopurity, and activity concentrations are greater than 3.15 GBq/ml (85 mCi/ml). The final pH of the product solution, which is 0.03M diethylenetriaminepentaacetate (DTPA), can now be adjusted to user specifications.

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Abstract  

The fractional cumulative yields of135I,138Xe and140Ba in the particle (30 MeV) induced fission of232Th have been determined following the growth and decay of135gXe,138gCs and140La, respectively, employing high resolution gamma ray spectroscopy. The fractional cumulative yield values are 0.766±0.02, 0.813±0.03 and 0.991±0.004, respectively. The analysis of the data indicates a broader width of charge distribution () compared to the normally observed =0.56±0.06 for thermal neutron fission of235U.

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Acta Microbiologica et Immunologica Hungarica
Authors:
S. S. Kanwar
,
M. Srivastava
,
S. S. Chimni
,
I. A. Ghazi
,
R. K. Kaushal
, and
G. K. Joshi

Lipase (EC 3.1.1.3) is a tri-acylglycerol ester hydrolase, catalysing the hydrolysis of tri-, di-, and mono-acylglycerols to glycerol and fatty acids. To study the effect of adsorption of a lipase obtained from Bacillus coagulans BTS-1, its lipase was immobilized on native and activated (alkylated) matrices, i.e. silica and celite. The effect of pH, temperature, detergents, substrates, alcohols, organic solvent etc. on the stability of the immobilized enzyme was evaluated. The gluteraldahyde or formaldehyde (at 1% and 2% concentration, v/v) activated matrix was exposed to the Tris buffered lipase. The enzyme was adsorbed/entrapped more rapidly on to the activated silica than on the activated celite. The immobilized lipase showed optimal activity at 50ºC following one-hour incubation. The lipase was specifically more hydrolytic to the medium C-length ester (p-nitro phenyl caprylate than p-nitro phenyl laurate). The immobilization/entrapment enhanced the stability of the lipase at a relatively higher temperature (50ºC) and also promoted enzyme activity at an acidic pH (pH 5.5). Moreover, the immobilized lipase was quite resistant to the denaturing effect of SDS.

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The thermal decomposition behaviour of copper oxalate hemihydrate and its complexes with different amines has been studied by TG and DTA methods in nitrogen and air atmospheres. The complexes CuC2O4 · 0.5 H2O, CuC2O4(NH3)2 and CuC2O4(py) produced Cu2O as final residue after decomposition, whereas, another group of complexes, CuC2O4(EtNH2)2, CuC2O4(MeNH2)2, CuC2O4(en)2 and CuC2O4(An)2, gave a final residue of CuO. All the complexes decomposed without forming any isolable stable intermediate; an exception was CuC2O4(en)2, which formed a binuclear intermediate complex, [CuC2O4en]2.

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A two-year field experiment was conducted to study the effect of three zinc levels 0, 20 kg ZnSO4 ha−1 and 20 kg ZnSO4 ha−1 + foliar spray of 0.5% ZnSO4 solution on plant height, leaf area, shoot biomass, photosynthetic rate and chlorophyll content in different wheat genotypes. Increasing zinc levels was found to be beneficial in improving growth and physiological aspects of genotypes. Soil application + foliar spray proved to be the best application in improving all the parameters. Zinc application brought about a maximum increment limit of 41.8% in plant height, 101.8% in leaf area, 86% in shoot biomass and 51.1% in photosynthetic rate irrespective of stages and year of study. A variation was found to occur among genotypes in showing responses towards zinc application and PBW 550 was found to be more responsive.

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