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- Author or Editor: N. Gupta x
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Abstract
The paper analyses 2339 research papers appearing in 330 journals covered in Medicinal and Aromatic Plants Abstracts, India (1983) on the basis of their broad subject fields such as agronomy, phytochemistry, pharmacology and clinical research; their country of origin; plant genera and their species; and by type of investigation. Under each of the broad subject fields and major genera, an attempt has been made to identify the nature and focus of research in different countries through minimal level content analysis. Special focus of the paper has been the analysis of Indian publication output.
Abstract
Polyamino group-containing resins act both as chelating ion exchangers and weakly basic anion exchangers depending upon the species in contact in the solution. In the present work, ion exchangers based on polyamine incorporated polysaccharides (cellulose and galactomannan or guaran) have been used for removal of radioisotopes of185W as WO 4 2– ,99Mo as MoO 4 2– and125Sb as Sb3+ from their separate aqueous solutions. These chelating anion exchangers have been synthesized by reaction of polysaccharides with epichlorohydrin followed by the respective polyamines as nucleophiles in a strongly alkaline medium. WO 4 2– and MoO 4 2– are adsorbed from their aqueous solutions through anion exchange process by chloride form of cellulose-triethylenetetraamine (cellulose-trien), cellulose-tetraethylenepentaamine (cellulose-tetren), guaran-triethylenetetraamine (guar-trien) and guar-tetraethylenepentaamine (guar-tetren) weakly basic anion exchangers. Guar-tetren chelating polymer has been found to be highly selective for125Sb isotopes presumably due to the presence of chelating cis-hydroxy and tetren groups in the galactomannan matrix.
Investigations of the thermal stability of detonating fuse containing 10 g pentaerythrol tetranitrate (PETN) revealed that the cord burnt under unconfinement at 403 K. Under confinement in a steel pipe or copper tube there was a partial detonation at 403 K. In order to characterize the thermal stability of PETN and pyrotechnic composition used in fuse head of electric detonators differential thermal analysis (DTA) was used.
In this study, we describe the membrane lipid composition of eight clinical isolates (azole resistant and sensitive strains) of Candida albicans isolated from AIDS/ HIV patients. Interestingly, fluorescence polarization measurements of the clinical isolates displayed enhanced membrane fluidity in fluconazole resistant strains as compared to the sensitive ones. The increase in fluidity was reflected in the change of membrane order, which was considerably decreased (decrease in fluorescence polarization “p” value denotes higher membrane fluidity) in the resistant strains. The ergosterol content in azole susceptible isolates was greater, almost twice as compared to the resistant isolates. However, no significant alteration was observed in phospholipid and fatty acid composition of these isolates. Labeling experiments with fluorescamine dye revealed that the percentage of phosphatidylethanolamine exposed to the membrane’s outer leaflet was higher in the resistant strains as compared to the sensitive strains, indicating increased floppase activity of the two major ABC drug efflux pumps, CDR1 and CDR2 possibly due to their overexpression in resistant strains. The results of the present study suggest that changes in the status of membrane lipid phase especially the ergosterol content and increased activity of drug efflux pumps by overexpression of ABC transporters, CDR1 and CDR2 might contribute to fluconazole resistance in C. albicans isolated from AIDS/HIV patients.
Solvent free reactions
Reactions of nitrophenols in 8-hydroxyquinoline–benzoic acid eutectic melt
Abstract
Reactions of nitrophenols have been studied in the eutectic melt of 8-hydroxyquinoline–benzoic acid, where it reacted with 8-hydroxyquinoline. The reactions were also carried out in solution. The reaction products obtained from both the methods were characterized by FT-IR, differential scanning calorimetry, X-ray diffraction technique and microstructural investigations. The reaction products obtained from eutectic melt were analyzed for C, H, N. The results showed that reaction products obtained from both the methods are same. An attempt has been made to propose the overall mechanism of the reaction in the eutectic melt.
Abstract
Copolymers of vinyl acetate and ethylene were prepared by emulsion polymerization using ammonium persulphate and sodium metabisulphite as initiators in presence of cyclohexane. Several copolymer samples were prepared by changing initial pressure of ethylene from 100 to 250 psi. The copolymer composition was determined by 1H-NMR and thermogravimetric analysis in nitrogen atmosphere.
Abstract
The extraction of plutonium(IV), uranium(VI), zirconium(IV), europium(III) and ruthenium(III) with 
-pre-irradiated n-dodecane solutions of methylbutyl substituted hexanamide (MBHA), octanamide (MBOA) and decanamide (MBDA) from 3.5M HNO3 has been studied as a function of absorbed dose up to 184×104 Gray. The distribution ratios (Kd) of uranium(VI) decreased gradually up to a dose of 50×104 Gray and became almost constant thereafter, while ruthenium(III) and europium(III) were not extracted in the entire dose range studied. The Kd values of Pu(IV) decreased gradually up to 10×104 Gray, for MBOA, and 30×104 Gray for MBHA and MBDA and then increased up to a dose of 72×104 Gray, indicating the synergistic effect of radiolytic products at higher doses. The extraction of zirconium(IV) was found to increase gradually up to 72×104 Gray. However, the steep fall in Kd values of plutonium(IV), zirconium(IV) beyond a dose of 72×104 Gray was atrributed to third phase formation. The radiolytic degradation of amides was monitored by quantitative IR spectroscopy and was found to follow the order MBOA>MBDA>MBHA at 184×104 Gray having the amines and carboxylic acids as the main radiolytic products.
Carotenoids are important micronutrients required by humans for growth and development. Yellow maize among cereals possesses sufficient carotenoids, and thus, it is important to genetically dissect such traits for proper utilization in breeding programme. Twenty-one maize hybrids generated using novel inbreds with rare allele of β-carotene hydroxylase (crtRB1) that enhances kernel β-carotene, were evaluated at two diverse maize growing locations. Lutein, zeaxanthin and β-cryptoxanthin were positively correlated, while β-carotene showed negative correlation with other carotenoids. Grain yield did not show association with carotenoids. Preponderance of additive gene action was observed for lutein, zeaxanthin, β-cryptoxanthin and β-carotene. Experimental hybrids were much superior for kernel β-carotene compared to commercial hybrids. Based on SCA effects, high yielding experimental hybrids were identified for provitamin A and non-provitamin A carotenoids. These novel hybrid combinations of maize possessing rare allele of crtRB1 hold promise in maize biofortification programme to alleviate vitamin A deficiency and degenerative diseases in humans.
Abstract
The extraction behavior of uranium(VI), plutonium(IV) and some fission products like zirconium(IV), ruthenium(III) and europium(III) from 3.5M nitric acid with 
-irradiated organic phase pre-equilibratedn-dodecane solutions of dihexyl derivatives of hexanamide (DHHA), octanamide (DHOA) and decanamide (DHDA) has been investigated as a function of absorbed dose upto 184·104 Gy. The results indicate that the extraction of uranium(VI) decreases gradually with dose upto 72·104 Gy and becomes almost constant thereafter, while, the extraction of plutonium(IV) decreases upto a dose of 20·104 Gy and then increases rapidly up to a dose of 82·104 Gy indicating synergistic effects of radiolytic products formed at higher doses. Extraction of zirconium(IV) increases gradually upto a dose of 72·104 Gy. Europium(III) does not get extracted with any of these amides in the entire dose range (0–184·104 Gy) studied, however, ruthenium shows insignificant increase in extraction with dose. The decrease inD values noticed in the case of plutonium and zirconium after the dose of 72·104 Gy which was attributed to the third phase formation and emulsification. Infrared studies confirm the final products of radiolysis as the respective amines and carboxylic acids. The degraded amide contents have been estimated by quantitative IR spectrophotometric technique. Extraction data obtained for uranium(VI) and plutonium(IV) with TBP/n-dodecane system have also been compared under similar experimental conditions.
