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981.
Basak A Mandal S Kumar Das A Bertolasi V 《Bioorganic & medicinal chemistry letters》2002,12(6):873-877
Monocyclic enediynyl amides 2a-2c have been synthesized via the corresponding free amine 5. Kinetic studies in chloroform revealed the reactivity of these amides towards Bergman cyclization to be less than that of the corresponding sulfonamides. However, differential scanning calorimetry (DSC) measurements in the solid state and DNA-cleavage studies in aqueous buffer showed higher reactivity for the amides than the sulphonamides. 相似文献
982.
The uptake of water vapour by 20 different polyaminoacids have been evaluated by an isopiestic vapour pressure technique in absence of solute at three different temperatures (22 degrees C, 30 degrees C and 37 degrees C). The water vapour adsorption isotherm for different polyaminoacids in the range of water activity varying between zero and unity apparently agreed with that expected from a type III BET isotherm. From the linear BET plots, obeyed in the lower range of water activity, the BET constants n(m) and Qm for different polyamines have been evaluated. The amount of water vapour adsorbed (n1) was calculated in moles/kg of polyaminoacids as well as in moles/mole of amino acid residue. Its value at unit water activity (deltan(o)1) has been evaluated by an extrapolation method and the results support that the multilayer adsorption of water vapour at the interface of polyaminoacids takes place. Values of deltan(o)1 are strictly comparable in terms of moles per kg rather than mole per mole unit. In case of beta lactoglobulin (betalg), lysozyme and BSA, theoretically obtained deltan(o)1 values were observed to be considerably larger than experimental values of deltan(o)1. This indicated that amino acid residues in the polypeptide release a large amount of water due to the formation of a globular structure. Using the Bull equation in the integrated form, standard free energies, deltaGo(w) for water-polyamino acid binding interaction at two different temperatures have been evaluated. Based on the Clausius-Clapeyron equation in an integrated form, the integral enthalpy for water-polyamino acid interaction has also been evaluated. 相似文献
983.
984.
Vertical Profile of Phosphatase Activity in the Sundarban Mangrove Forest,North East Coast of Bay of Bengal,India 总被引:2,自引:0,他引:2
Impact of phosphate solubilizing bacteria along with soil phosphatase activity on phosphorous cycle was found to be quiet interesting in the Sundarban mangrove ecosystem. Soil phosphatase activity showed a decreasing pattern with increase in depth [soil phosphatase activity (μg pnp produced g?1 dry wt of soil) = 906.85 – 5.6316 Depth (cm)] from the deep forest region of the Sundarban forest ecosystem. Soil salinity showed a very little effect on soil phosphatase activity whereas soil temperature and pH was found to show significant impact on the soil phosphatase activity. This ensured that the microbes associated with phosphate mineralization present in the Sundarban forest ecosystem are more tolerant to fluctuation in salinity than that of temperature and pH. A direct correlation was perceptible between the number of phosphate solubilizing bacteria and phosphatase activity in the soil during the study period from 2007 to 2012. Soil phosphate concentration was found to be directly governed by the soil phosphatase activity [The regression equation is: avg PO4?3-P (μg g?1 dry wt of soil) = 0.0311 + 0.000606 soil phosphatase activity (μg pnp produced g?1 dry wt of soil); R2 = 63.2%, p < 0.001, n = 62]. 相似文献
985.
B. B. Sahu M. R. Raghunath P. K. Meher D. K. Senapati P. C. Das B. Mishra A. K. Sahu P. Jayasankar 《Zeitschrift fur angewandte Ichthyologie》2014,30(1):195-199
The carcass traits and commercial characteristics of farmed freshwater Cirrhinus mrigala and Hypophthalmichthys molitrix were investigated to calculate yield data useful for programming semi‐automated processing units. Specimens with average weights of 2500 and 3400 g were collected from both mrigal and silver carps, respectively. Samples were taken from grow‐out culture ponds of the Central Institute of Freshwater Aquaculture (CIFA), Odisha State, India. Carcass and offal yields as well as carcass cutability were assessed. Head yields were recorded as 14.9 and 27.5% for mrigal and silver carp, respectively. The gutted yield, headless yield and skinless dressed round percentages were determined as 89.4, 74.5 and 67.6% for mrigal and 92.8, 65.4 and 62.0% for silver carps, respectively. The meat: bone ratio in filleting averaged 4.8 for mrigal and 3.1 for silver carp. The middle cut of mrigal had both the highest total yield percentage and highest meat yield, whereas this was equally distributed between both the fore and middle cuts in silver carp. In both mrigal and silver carp the dry matter, ether extract and protein percentages were highest in the fore cut followed by middle and hind cut. In silver carp the percentage fat content was found to be significantly higher than in mrigal. 相似文献
986.
987.
Huguette Gaelle Ngassa Mbenda Gauri Awasthi Poonam K Singh Inocent Gouado Aparup Das 《Journal of biosciences》2014,39(4):727-738
Cameroon, a west-central African country with a ~20 million population, is commonly regarded as ‘Africa in miniature’ due to the extensive biological and cultural diversities of whole Africa being present in a single-country setting. This country is inhabited by ancestral human lineages in unique eco-climatic conditions and diverse topography. Over 90% Cameroonians are at risk of malaria infection, and ~41% have at least one episode of malaria each year. Historically, the rate of malaria infection in Cameroon has fluctuated over the years; the number of cases was about 2 million in 2010 and 2011. The Cameroonian malaria control programme faces an uphill task due to high prevalence of multidrug-resistant parasites and insecticide-resistant malaria vectors. Above all, continued human migration from the rural to urban areas as well as population exchange with adjoining countries, high rate of ecological instabilities caused by deforestation, poor housing, lack of proper sanitation and drainage system might have resulted in the recent increase in incidences of malaria and other vector-borne diseases in Cameroon. The available data on eco-environmental variability and intricate malaria epidemiology in Cameroon reflect the situation in the whole of Africa, and warrant the need for in-depth study by using modern surveillance tools for meaningful basic understanding of the malaria triangle (host-parasite-vector-environment). 相似文献
988.
Rupam Dutta Subimal Laskar Probodh Borah Dhrubajyoti Kalita Bula Das Galib Zaman Nagendra Nath Barman Deep Prakash Saikia 《Molecular biology reports》2014,41(6):3677-3681
Assam hill goat (Capra hircus) is a prolific local goat in India. bone morphogenetic protein receptor (BMPR1B) gene was studied as a candidate gene for the prolificacy of goats. The objective of the present study was to detect the incidence of mutation in the exonic region of BMPR1B gene of Assam hill goat. Total 90 blood samples were collected randomly from different parts of Assam and genomic DNA were extracted using phenol–chloroform method. The quantity and quality of extracted DNA was examined by spectrophotometry and gel electrophoresis, respectively. PCR amplicon showed a product of 140 bp fragment of BMPR1B gene. The purified product upon digestion with AvaII showed monomorphic banding pattern and revealed wild type alleles with AA genotype. Nucleotide sequencing showed one new mutation 773 (G→C) which is found to be unique in Assam hill goat. Construction of tree at nucleotide level generates from the present experiment lies in common cluster which differs from the other breeds of goat. The analysis of polymorphism for BMPR1B in Assam hill goat indicates that the genetic factor responsible for prolificacy or multiple kidding rates is not related to the reported mutated alleles of BMPR1B gene. Therefore, attempts to be made to detect other SNPs for BMPR1B gene or otherwise effort should be made towards other fecundity gene which might be responsible for the prolificacy of Assam hill goat. 相似文献
989.
990.
Jaseetha Abdul Salam Nilanjana Das 《World journal of microbiology & biotechnology》2014,30(4):1301-1313
A new yeast strain was isolated from sugarcane cultivation field which was able to utilize lindane as sole carbon source for growth in mineral medium. The yeast was identified and named as Candida sp. VITJzN04 based on a polyphasic approach using morphological, biochemical and 18S rDNA, D1/D2 and ITS sequence analysis. The isolated yeast strain efficiently degraded 600 mg L?1 of lindane within 6 days in mineral medium under the optimal conditions (pH 7; temperature 30 °C and inoculum dosage 0.06 g L?1) with the least half-life of 1.17 days and degradation constant of 0.588 per day. Lindane degradation was tested with various kinetic models and results revealed that the reaction could be described best by first-order and pseudo first-order models. In addition, involvement of the enzymes viz. dechlorinase, dehalogenase, dichlorohydroquinone reductive dechlorinase, lignin peroxidase and manganese peroxidase was noted during lindane degradation. Addition of H2O2 in the mineral medium showed 32 % enhancement of lindane degradation within 3 days. Based on the metabolites identified by GC–MS and FTIR analysis, sequential process of lindane degradation by Candida VITJzN04 was proposed. To the best of our knowledge, this is the first report of isolation and characterization of lindane-degrading Candida sp. and elucidation of enzyme systems during the degradation process. 相似文献