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991.
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   
992.
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   
993.
994.
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   
995.
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   
996.
997.
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   
998.
The present study was conducted for optimization of in vitro substrates under aseptic conditions for interaction of Piriformospora indica with the medicinal plant Coleus forskohlii. It aims to test the effects of different substrates on P. indica colonization as well as growth parameters of the in vitro raised C. forskohlii. Interaction of in vitro C. forskohlii with root endophyte P. indica under aseptic condition resulted in increase in growth parameters in fungus colonized plants. It was observed that P. indica promoted the plant’s growth in all irrespective of substrates used for co-culture study. The growth was found inferior in liquid compared to semisolid medium as well as there was problem of hyperhydricity in liquid medium. P. indica treated in vitro plantlets were better adapted for establishment under green house compared to the non treated plants due to fungal intervention.  相似文献   
999.
Cefdinir, a semi-synthetic third generation cephalosporin antibiotic being considered as an emerging pollutant, demands removal from aquatic ecosystems. A yeast strain isolated from pharmaceutical wastewater which was identified as Ustilago sp. SMN03 by molecular techniques and was found to be capable of utilizing cefdinir as a sole carbon source. The isolate was found to degrade 81 % of cefdinir within 6 days under optimized conditions viz. pH 6.0, temperature 30 °C, a shaking speed of 120 rpm, an inoculum dosage of 4 % (w/v) and an initial cefdinir concentration of 200 mg L?1. Kinetic studies revealed that cefdinir degradation followed the pseudo-first order model, a rate constant of 0.222 per day and a half-life period of 3.26 days. Using LC–MS analysis, six novel intermediates formed during the cefdinir degradation were identified and characterized. FT-IR analysis showed that the functional groups ranging from 1,766 to 1,519 cm?1, characteristic for lactam ring were completely removed during the cefdinir degradation. The opening of the β-lactam ring was one of the major steps in the cefdinir degradation process. Based on the results from the present study, a possible pathway of cefdinir degradation by Ustilago sp. SMN03 was proposed. To the best of our knowledge, this is the first report on microbial degradation of cefdinir by yeast.  相似文献   
1000.
RelMtb, a GTP pyrophosphokinase encoded by the Mycobacterium tuberculosis (Mtb) genome, catalyzes synthesis of (p)ppGpp from ATP and GDP(GTP) and its hydrolysis to GDP(GTP) and pyrophosphate to mediate stringent response, which helps bacteria to survive during nutrient limitation. Like other members of Rel_Spo homologs, RelMtb has four distinct domains: HD, Rel_Spo (RSD), TGS and ACT. The N-terminal HD and RSD are responsible for (p)ppGpp hydrolysis and synthesis, respectively. In this study, we have dissected the rel Mtb gene function and determined the minimal region essential for (p)ppGpp synthetic activity. The RelMtb and its truncated derivatives were expressed from an arabinose inducible promoter (P BAD ), and in vivo functional analyses were done in a (p)ppGpp null Escherichia coli strain. Our results indicate that only 243 amino acids (188–430 residues) containing fragment are sufficient for RelMtb (p)ppGpp synthetic activity. The results were further confirmed by in vitro assays using purified proteins. We further characterized the RSD of RelMtb by substituting several conserved amino acids with structurally related residues and identified six such residues, which appeared to be critical for maintaining its catalytic activity. Furthermore, we have also extended our analysis to an RSD encoding gene rv1366 of Mtb, and experimental results indicated that the encoded protein Rv1366 is unable to synthesize (p)ppGpp.  相似文献   
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