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51.
The present study was carried out to explore the seroprevalence of brucellosis in yaks of North-Eastern hilly yak tracts of Arunachal Pradesh, India. Of 374 animals tested, 23.79, 21.11 and 18.98% were found positive for brucellosis using avidin-biotin ELISA (AB-ELISA), Rose-Bengal plate test (RBPT) and standard tube-agglutination test (STAT), respectively. The relative sensitivity and specificity for STAT were 79.77 and 100%, respectively and the same for RBPT were 88.76 and 100%, respectively in comparison to AB-ELISA. The alarming prevalence as recorded was highest among the yak cows (31.42%) followed by heifers (23.85%) and bulls (8.88%). The immune response in yaks following standard dose of calfhood vaccination with Brucella abortus strain 19 vaccine showed that protective antibody level persisted up to 210 days. This is the first report from India on prevalence of brucellosis and immunization with B abortus strain 19 vaccine in yaks. The present investigation would be a valuable guideline for future control measure and eradication programme of brucellosis in yaks.  相似文献   
52.
Aroma compounds partition between the dispersed and the continuous phases in emulsions, and phase transitions in the lipid droplets profoundly affect the position of the equilibrium. In the present study, the release of ethyl butyrate, ethyl pentanoate, ethyl heptanoate, and ethyl octanoate from a series of sodium caseinate-stabilized, n-eicosane emulsions was investigated as a function of solid and liquid lipid droplet concentration. For all compounds, headspace volatile concentrations above the solid droplet emulsions were higher than those above the liquid droplet emulsions. The interaction with liquid droplets could be modeled in terms of volume-weighted bulk partition coefficients while the more nonpolar volatiles bound to the surface of solid lipid droplets. The amount of volatiles bound to solid surfaces increased with aqueous concentration up to a critical point and then rapidly increased. The critical point corresponds to the dissolution of the solid lipid in a phase of adsorbed volatile. The binding of volatiles to both solid and liquid eicosane droplets is reversible.  相似文献   
53.
Ghosh M 《Fitoterapia》2009,80(2):91-95
A 30 KDa monomeric acidic lectin-like protein was purified from the leaves of an important medicinal herb, Withania somnifera (L.) Dunal (Solanaceae), by a series of gel filtration and affinity chromatography methods. The inhibitory concentration of the protein ranged from 7 microg to 11 microg against major phytopathogens under in vitro conditions. The peptide sequence showed similarity to concanavalin A like lectin from Canavalia ensiformis and caused distinct cell wall adhesion of the protein treated hyphae under SEM. Further, the antifungal activity of the protein was compared with standard lectins like concanavalin A, phytohemagglutinin and wheat germ agglutinin.  相似文献   
54.
The functional properties of wheat are largely dictated by composition and interactions of the gluten proteins. All flours contain gliadin and glutenin, but produce baked products of varying quality, which provides evidence that gluten proteins from different wheats possess different properties. A common method to study differences in gluten properties, which is utilized in this study, is fractionation/reconstitution experiments to understand how various gliadin to glutenin ratios and how fractions from different wheat sources affect gluten aggregation properties. Gliadin and glutenin from a vital wheat gluten were fractionated with 70% ethanol and reconstituted at various gliadin to glutenin ratios. Gliadin and glutenin from a Canadian eastern soft, eastern hard and western hard wheat (14% moisture) were fractionated and substituted between flours at the native gliadin to glutenin ratio. Gluten combinations were evaluated with a Gluten Peak Tester at constant temperature and mixing. Varying gliadin to glutenin ratio showed that 50:50 is optimal for fast gluten aggregation while amount of glutenin dictates strength. Substitution experiments showed that replacing good quality gluten fractions with those from a lower quality wheat decreases gluten quality, and vice versa. Data also showed that cultivar specific differences in gliadin and glutenin are more important in dictating gluten strength (torque), while gliadin to glutenin ratio dictates aggregation time (PMT) independent of the source of fractions. The study demonstrated the ability of the improved method to evaluate gluten aggregation by controlling for all variables except the one being tested. The data also revealed information about gluten aggregation properties never before seen.  相似文献   
55.
Four bacterial strains with high balanced polygalacturonase (PG) and pectin lyase (PNL), and xylanase with minimal cellulase activity were used in jute retting. The 16S rDNA analysis revealed that the organisms were: Bacillus sp. L6 (GQ891097), Bacillus pumilus strain EK-17 (GQ891098), B. pumilus strain Geo-03-422 (GQ891103) and B. pumilus strain IK-MB12-518F (GQ891105). The microorganisms in different combinations of consortia showed synergistic effect resulting in increased PG (35.52-46.61 IU/g cell wet weight), PNL (39.79-72.12 U/ml), xylanase (0.705-0.840 μmol/ml/min) and little cellulase (0-0.153 μmol/ml/min) activities. The organisms in different combinations of consortia reduced the retting period from 11 to 13 days as compared to 19 days in the control. Microbial inoculation produced remarkable improvement in jute fibre strength (26.62-28.91 g/tex) and fineness (2.76-2.92 tex) over control. The pH of the post-retting water samples became acidic, and the electrical conductivity (Ec), chemical oxygen demand (COD) and hardness increased. The organisms could be adopted in industrial application for extraction of jute fibre.  相似文献   
56.
Bioaccumulation of mercury and histomorphological changes in the olfactory epithelium of Labeo rohita were investigated after exposing the fish to two sublethal concentrations of HgCl2 (66 and 132 μg/L) for 15 and 30 days. Mercury deposition increased in the tissue significantly (p < 0.05) with dose- and duration-dependent manner. Severe damage to the olfactory epithelium was evident. When fish exposed to 66 μg/L for 15 days, the histology of olfactory epithelium exhibited that mucous cell proliferation was upregulated and cell size was significantly increased from the control. Similar trends were found in 30 days exposure in both treated groups. Histology showed that mercury induced degeneration of columnar sensory cells, supporting cells and ciliated non-sensory cells and induced basal cell proliferation. Basal cell hyperplasia led to form intraepithelial proliferative lesion, thickening of epithelium, basal lamina disruption and cyst formation. Scanning electron microscopy revealed that mercury exposure at 66 μg/L caused clumping and loss of cilia, erosion in microridges on the supporting cells and proliferation of mucous cell opening. Complete degeneration of ciliated cells and cyst formation was observed in the fish when exposed to 132 μg/L HgCl2. This result suggests that prolonged exposure to mercury might cause irreversible damage to the olfactory epithelium and impair the olfactory function of fish.  相似文献   
57.
Seaweeds are important marine renewable resources. Use of seaweeds as fertilizers has allowed for substitution in place of conventional synthetic fertilizers. This study was conducted to examine the effect of seaweed liquid extract (SLE) on growth, yield, and nutrient uptake by hybrid maize. The experiments were conducted in ZARS, Vishweshwaraiah Canal farm, Mandya (Karnataka, India) during the rabi season of 2011–2013 to study the effect of foliar applications of Kappaphycus alvarezii (K sap) and Gracilaria edulis (G sap) sap on growth and yield response of hybrid maize “NAH 1137”. Three foliar sprays of both saps were applied at the rate of 2.5, 5.0, 7.5, 10, and 15.0% (v/v) along with water spray as a control at different stages of the crop. It was found that grain yield increased significantly by 18.54% and 26.04% for plants receiving 10% concentrations of both K. alvarezii and G. edulis sap respectively, over control. The increase in yield was attributed to increase in the number of rows in cob, cob length, and 100 grain weight. This investigation concludes that application of both the saps at 10% increased the nutrient uptake, grain, and stover yield over control.  相似文献   
58.
Long-term effect of mungbean inclusion in lowland rice-wheat and upland maize-wheat systems on soil carbon (C) pools, particulate organic C (POC), and C-stabilization was envisaged in organic, inorganic and without nutrient management practices. In both lowland and upland systems, mungbean inclusion increased very-labile C (Cfrac1) and labile C (Cfrac2) in surface soil (0–0.2 m). Mungbean inclusion in cereal-cereal cropping systems improved POC, being higher in lowland (107.4%). Lowland rice-based system had higher passive C-pool (11.1 Mg C ha?1) over upland maize-based system (6.6 Mg C ha?1) indicating that rice ecology facilitates the stabilization of passive C-pool, which has longer persistence in soil. Organic nutrient management (farmyard manure + full crop residue + biofertilizers) increased Cfrac1 and carbon management index (CMI) over inorganic treatment. In surface soil, higher CMI values were evident in mungbean included cropping systems in both lowland and upland conditions. Mungbean inclusion increased grain yield of cereal crops, and yield improvement followed the order of maize (23.7–31.3%) > rice (16.9–27.0%) > wheat (lowland 7.0–10.7%; upland 5.4–16.6%). Thus, the inclusion of summer mungbean in cereal-cereal cropping systems could be a long-term strategy to enrich soil organic C and to ensure sustainability of cereal-cereal cropping systems.  相似文献   
59.
An efficient plant propagation system through somatic embryogenesis was established in Cymbopogon pendulus, an aromatic grass followed by analysis of genetic status of regenerants using ISSR markers. Optimum embryogenic callus induction was observed on MS basal medium supplemented with 13.57 μM 2,4-dicholorophenoxyacetic acid (2,4-D) with 8.88 μM N6-benzyladenine (BA). Subsequent culturing of embryogenic calli on MS medium containing 4.52 μM 2,4-D and 8.88–13.32 μM BA gave maximum number of somatic embryos. Addition of coconut water (CW) promoted induction, growth and differentiation of callus and somatic embryogenesis. Further development of embryos into plantlets was achieved on MS medium supplemented with lower concentration of biotin and calcium pantothenate (CaP) along with BA (4.44–13.32 μM) and kinetin (2.32–4.65 μM). The root meristems were established on half strength MS medium containing 2% sucrose and 2.46–9.84 μM Indole3-butyric acid (IBA) and successfully established in soil with 77.8% survival rate in field condition. Thirteen randomly selected regenerated clones were screened using six ISSR primers. Nine clones produced similar monomorphic amplification profiles while remaining clones showed minor variation with absence of certain parental bands and appearance of unique band. Majority of the regenerants maintained genetic fidelity with the generation of few variants as evidenced from similarity matrix estimates using Nei Li's coefficient of similarity data.  相似文献   
60.
ABSTRACT: Picobirnaviruses (PBV) are small, non-enveloped viruses with a bisegmented double-stranded RNA genome. In this study a PBV strain, PBV/Horse/India/BG-Eq-3/2010, was identified in the faeces of a 10 month old weaned female foal with diarrhoea in January 2010 from Kolkata, India. Surprisingly, sequence comparison and phylogenetic analysis of a short stretch of the RNA dependent RNA polymerase gene revealed close genetic relatedness (> 98% nucleotide identity) to a human genogroup I PBV strain (Hu/GPBV1) detected earlier from the same part of India. Our observations together with earlier findings on genetic relatedness between human and animal PBV warrant further studies on zoonotic potential.  相似文献   
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