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Abstract  

Cosmic ray neutron interactions with indium, used as electrical contact within a Ge diode, the diode itself and the surrounding materials can give rise to a large number of photopeaks in the 50 to 1300 keV region of background spectra of Ge spectrometers with a passive shield. The nuclear processes and decays involved in the production of these photopeaks are discussed. These cosmic ray produced photopeaks are compared with those due to primordial radionuclides. Some useful information can be drawn from these measurements on the contribution of the cosmic rays on the background of Ge detectors with a passive shield.

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An ingredient of ‘Dasamoola’ and ‘Laghupanchamoola’ group of drugs, the source of ‘Brihati’ has been controversial. Although the dried root of Solanum anguivi is considered as the source of the drug ‘Brihati’ according to the Ayurvedic Pharmacopoeia of India, closely related and morphologically similar few species like Solanum torvum, Solanum melongena, Solanum incanum, and Solanum insanum are known as its substitutes. In the present study, a high-performance thin-layer chromatography (HPTLC) method was developed and validated for the chemoprofiling and quantitative estimation of glycoalkaloid solamargine from 5 species of the genus Solanum as well as market samples. The developed method was precise, accurate, robust, specific, and linear. The results showed that S. incanum has the highest content of solamargine, followed by S. insanum. Out of the 9 market samples analyzed, solamargine was detected only in 3 samples. Unsupervised pattern recognition techniques, such as principal component analysis and hierarchical cluster analysis, were used to analyze the complex fingerprint patterns and to predict the grouping of samples. The method clearly segregated the field and market samples. Our study is the first attempt to evaluate the drug ‘Brihati’ and the market samples using HPTLC.

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The F1 and F2 progenies of a ten-parent diallel cross (excluding reciprocals) were analysed for the combining ability of quantitative traits in six-rowed barley (Hordeum vulgare L.). significant differences were indicated between the parents, F1s and F2s for all the characters studied. The gca and sca components of variance were significant for all the traits. Both additive and non-additive gene effects were involved in the genetic control of the characters; however, non-additive gene effects were observed to be predominant. Among the parents RD 2035, RD 2052, RD 2503 and BL 2 were the best general combiners for grain yield and average to high combiners for other important traits.The parents RD 2552 and RD 387 were the best general combiners for dwarfness. The best specific crosses for grain yield were RD 2503 × RD 2585,RD 2035 × RD 2052, RD 2035 × BL 2, RD 2052 × BL 2, RD 2508 × RD 2552, RD 2552 × RD 2585 and Rd 2052 × RD 2552 in both the F1 and F2 generations. These crosses were higher yielders and in most of the crosses one of the parents involved was a good combiner, indicating that such combinations can be expected to produce desirable transgressive segregants. All the best crosses for grain yield also showed average to high sca effects for most of the yield components. Most of the specific crosses for grain yield involved high × average, average × average and average × poor general combiners. To ensure a further increase in grain yield, the combination of desirable yield components is advocated. The inclusion of F1 hybrids showing high sca, and having parents with good gca, in multiple crosses, bi-parental mating or diallel selective mating could prove a worthwhile approach for further amelioration of grain yield in six-rowed barley.

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A field study conducted for two years (2002–04) at New Delhi showed that the seed yield (1.80 t ha −1 ) of rocket salad ( Eruca sativa Mill.) obtained by applying 5 t ha −1 pressmud compost based on distillery effluent + half the recommended dose of NPKS (recommended dose: 60 kg N, 13 kg P, 25 kg K and 20 kg S ha −1 ) was on par with the seed yield (1.69 t ha −1 ) recorded with the recommended dose of NPKS. However, the seed yield recorded with the former treatment significantly exceeded that obtained with 5 t ha −1 of a 1:1 mixture of fly ash and distillery effluent + half the recommended dose of NPKS (by 30.4%) or 5 t ha −1 of dry Jatropha curcas leaves + ½ NPKS (by 24.1%). On average, distillery effluent-based pressmud compost + ½ NPKS induced a perceptible increase in the soil-available NPK, recorded after the harvest of rocket salad, compared to the initial fertility status. The uptake of NPKS in the seed and stover of rocket salad was the highest after the application of pressmud compost, closely followed by the recommended dose of NPKS, and the lowest in the control. The residual effect of treatments given to rocket salad was significant on the fodder yield of succeeding sorghum [ Sorghum bicolor (L.) Moench]. The fodder yield recorded with pressmud compost + ½ NPKS was significantly higher than the other treatments. The application of pressmud compost alone was also significantly superior to the same rate of fly ash + effluent mixture or dry Jatropha leaves with respect to the seed yield of rocket salad, residual fertility after the harvest of rocket salad and the fodder yield of succeeding sorghum.

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A new gall-inducing and lirellate lichenicolous fungus, Plectocarpon diedertzianum Y. Joshi, Upadhyay et Chandra, is described from Kumaun Himalayan regions of India colonising thallus of various parmelioid lichens (Flavoparmelia caperata, Myelochroa aurulenta, Parmotrema crinitum, P. melanothrix, P. reticulatum, Punctelia subrudecta). The new species is characterised by black, epruinose rounded to lirellate ascomata with a carbonised surface and a ±thalline pseudomargin, as well as a carbonised, sterile stromatic tissue, 4-spored asci and 3-septate hyaline ascospores.

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Combining ability analysis in spring wheat (Triticum aestivum L. em. Thell) involving 10 diverse parents and their 45 F1 and F2 progenies indicated significant differences between the parents for GCA and between the crosses for SCA for all the characters studied. The GCA and SCA components of variance were significant for all the traits. However, the GCA component of variance was predominant, indicating the predominance of additive gene effects for the traits studied. Among the parents HD 2329, Raj 1972, HD 2285 and HD 2428 were the best general combiners for grain yield and average to high combiners for other important traits. The best specific crosses for grain yield were CPAN 3004 × Durgapura 65, Sonalika × HD 2329, Raj 3077 × CPAN 3004, Raj 3077 × HD 2428 and HD 2428 × WH 157.The parent Raj 1972 was the best general combiner for grain yield and protein content, while Raj 3077 and Lok-1 were the best general combiners for protein content. The most suitable specific crosses for protein content were HD 2329 x HD 2285, HD 2428 × Raj 1972 and CPAN 3004 × WH 157. Most of the specific crosses for grain yield and protein content involved high × average, average × average or average × poor general combiners. To ensure a further increase in grain yield along with high protein, combinations of desirable yield components are advocated. The exploitation of additive and non-additive gene actions through bi-parental mating and/or diallel selective mating systems are suggested for a tangible advance in grain yield coupled with high protein in spring wheat.

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Summary

A simple, reversed-phase HPLC method has been developed for rapid, simultaneous quantification of phenylephrine hydrochloride, guaiphenesin, ambroxol hydrochloride, and salbutamol (as salbutamol sulphate) in a commercial cough-cold liquid formulation. The compounds were separated on a 250 mm × 4.6 mm C8 column with a gradient prepared from pH 3.0 phosphate buffer and 1:1 methanol-acetonitrile as mobile phase at a flow rate of 1.0 mL min−1. Elution of the analytes was achieved in less than 15 min. Detection was by UV absorbance at 273 nm for phenylephrine hydrochloride and guaiphenesin and 225 nm for ambroxol hydrochloride and salbutamol. Percentage recovery and RSD were, respectively, 100.09% and 0.22% for phenylephrine hydrochloride, 100.43% and 0.50% for guaiphenesin, 100.91% and 0.70% for ambroxol hydrochloride, and 100.54% and 0.55% for salbutamol. The components of the syrup formulation were quantified on the basis of the peak areas obtained from freshly prepared standard solutions. The method was validated in accordance with ICH guidelines.

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The contents of total phenols and orthodihydric phenols, specific activities of polyphenol oxidase (PPO), peroxidase (PO) and catalase in leaves of powdery mildew resistant (NLM and HM 350) and susceptible (T 8 and HM 65) genotypes of fenugreek were estimated at 40, 80 and 100 days after sowing (DAS) in inoculated (E1) and natural (E2) environments. The levels of all the biochemical constituents were higher in resistant genotypes than in susceptible ones before the appearance of disease (40 DAS) in both the environments. In response to infection, an increase was observed in contents of all the parameters except catalase activity in all the genotypes. However, at higher disease severity levels of all the biochemical parameters decreased invariably in all the genotypes except activities of PPO and PO which increased further in susceptible genotypes in both the environments. The role of phenolics and oxidative enzymes in determining resistance in fenugreek against powdery mildew disease has been highlighted.

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Summary

A simple, rapid, precise, and accurate, stability-indicating reversed phase high performance liquid chromatographic method was developed and validated for simultaneous determination of metformin HCl and repaglinide. The chromatographic separation was achieved on YMC Pack AM ODS (5 μm, 250 mm length × 4.6 mm i.d.) column at a detector wavelength of 210 nm, using an isocratic mobile phase consisting of methanol and 10 mM potassium dihydrogen phosphate buffer (pH 2.5) in a ratio of 70:30 v/v at a flow rate of 1 mL min−1. The retention times for metformin and repaglinide were found to be 2.6 and 11.3 min, respectively. The drugs were exposed to thermal, photolytic, hydrolytic, and oxidative stress conditions, and the stressed samples were analyzed by the proposed method. Validation of the method was carried out as per International Conference on Harmonization (ICH) guidelines. Linearity was established for metformin and repaglinide in the range of 5–200 μg mL−1 and 1–200 μg mL−1, respectively. The limits of detection were 0.3 μg mL−1 and 0.13 μg mL−1 for metformin and repaglinide, respectively. The method was found to be specific and stability-indicating as no interfering peaks of degradants and excipients were observed. The proposed method is hence suitable for application in quality-control laboratories for quantitative analysis of both the drugs individually and in combination, since it is simple and rapid with good accuracy and precision.

Open access
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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