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71.
Glycosylated α-galactosidase (melibiase) has been purified from white chickpea ( Cicer arietinum ) to 340-fold with a specific activity of 61 units/mg. Cicer α-galactosidase showed a M(r) of 45 kDa on SDS-PAGE and by MALDI-TOF. The optimum pH and temperature with pNPGal were 4.5 and 50 °C, respectively. The K(m) for hydrolysis of pNPGal was 0.70 mM. Besides hydrolyzing the pNPGal, Cicer α-galactosidase also hydrolyzed natural substrates such as melibiose, raffinose, and stachyose very effectively; hence, it can be exploited commercially for improving the nutritional value of soy milk. Galactose was found to be a competitive inhibitor. The property of this enzyme to cleave the terminal galactose residues can be utilized for converting the group B erythrocytes to group O erythrocytes. 相似文献
72.
Benjamin W. Newcomer M. Shonda Marley Patricia K. Galik Yijing Zhang Kay P. Riddell David W. Boykin Arvind Kumar Leah A. Kuhnt Julie A. Gard M. Daniel Givens 《Canadian journal of veterinary research》2013,77(3):170-176
Bovine viral diarrhea virus (BVDV) is a widespread bovine pathogen capable of causing disease affecting multiple body systems. Previous studies have shown 2-(2-benzimidazolyl)-5-[4-(2-imidazolino)phenyl]furan dihydrochloride (DB772) effectively prevents BVDV infection in cell culture. The aim of this project was to assess the efficacy of DB772 for the prevention of acute BVDV infection. Four calves seronegative to BVDV were treated with DB772 and another 4 calves were treated with diluent only on the same dosing schedule. Each calf was subsequently challenged intranasally with BVDV. Virus was isolated consistently from untreated calves on days 4 to 8, while treated calves remained negative by virus isolation during this period. Azotemia was exhibited by all treated calves on day 4 resulting in the euthanasia of 1 calf on day 10 and the death of another on day 13. Virus was isolated from the 2 remaining treated calves on day 14 or 21. On day 21, both remaining treated calves and all 4 untreated calves had anti-BVDV antibody titers > 1:2048. This pilot study indicates that DB772 temporarily prevented acute disease due to BVDV, but carries a significant concern of renal toxicity. 相似文献
73.
N.Manikanda BOOPATHI Gat SWAPNASHRI P.KAVITHA S.SATHISH R.NITHYA Wickneswari RATNAM Arvind KUMAR 《水稻科学》2013,20(1):25-30
Near isogenic lines carrying large-effect QTL (qtl12.1), which has a consistent influence on grain yield under upland drought stress conditions in a wide range of environments, were evaluated under water stress in the fields. The line which gave higher yield under drought was crossed with a local elite line, PMK3, and forwarded to F2:3 generation. Significant variation was found among the F2:3 lines for agronomic traits under water stress in the fields. Low to high broad sense heritability (H) for investigated traits was also found. Water stress indicators such as leaf rolling and leaf drying were negatively correlated with plant height, biomass and grain yield under stress. Bulked segregant analysis (BSA) was performed with the markers in the vicinity of qtl12.1, and RM27933 was found to be segregated perfectly well in individual components of drought resistant and drought susceptible bulks which were bulked based on yield under water stress among F2:3 lines. Hence, this simple and breeder friendly marker, RM27933, may be useful as a potentially valuable candidate marker for the transfer of the QTL qtl12.1 in the regional breeding program. Bioinformatic analysis of the DNA sequence of the qtl12.1 region was also done to identify and analyze positional candidate genes associated with this QTL and to ascertain the putative molecular basis of qtl12.1. 相似文献
74.
75.
Phytochemical investigation of the ethanolic extract of twigs of Kigelia pinnata DC. afforded one new iridoid 7-hydroxy eucommiol (1), and nine known compounds (2-10). The structure of compounds was elucidated by extensive spectroscopic methods, including 1D, 2D NMR experiments and MS analysis. All these compounds were evaluated for GLUT4 translocation modulatory effect in skeletal muscle cells. Four of the tested compounds 1, 5, 6 and 7 showed significant stimulation of GLUT4 translocation to cell surface in skeletal muscle cells without any adverse effect on cell viability. Effect of these four compounds was concentration-dependent and comparable to standard drug rosiglitazone. These findings indicate that constituents of K. pinnata may provide leads for the therapeutics for insulin resistance and diabetes. 相似文献
76.
Ma. Carmelita R. Alberto Reiner Wassmann Takashi Hirano Akira Miyata Arvind Kumar Agnes Padre Modesto Amante 《Agricultural and Forest Meteorology》2009,149(10):1737-1750
The seasonal fluxes of heat, moisture and CO2 were investigated under two different rice environments: flooded and aerobic soil conditions, using the eddy covariance technique during 2008 dry season. The fluxes were correlated with the microclimate prevalent in each location. This study was intended to monitor the environmental impact, in terms of C budget and heat exchange, of shifting from lowland rice production to aerobic rice cultivation as an alternative to maintain crop productivity under water scarcity.The aerobic rice fields had higher sensible heat flux (H) and lower latent heat flux (LE) compared to flooded fields. On seasonal average, aerobic rice fields had 48% more sensible heat flux while flooded rice fields had 20% more latent heat flux. Consequently, the aerobic rice fields had significantly higher Bowen ratio (0.25) than flooded fields (0.14), indicating that a larger proportion of the available net radiation was used for sensible heat transfer or for warming the surrounding air.The total C budget integrated over the cropping period showed that the net ecosystem exchange (NEE) in flooded rice fields was about three times higher than in aerobic fields while gross primary production (GPP) and ecosystem respiration (Re) were 1.5 and 1.2 times higher, respectively. The high GPP of flooded rice ecosystem was evident because the photosynthetic capacity of lowland rice is naturally large. The Re of flooded rice fields was also relatively high because it was enhanced by the high photosynthetic activities of lowland rice as manifested by larger above-ground plant biomass. The NEE, GPP, and Re values for flooded rice fields were −258, 778, and 521 g C m−2, respectively. For aerobic rice fields, values were −85, 515, and 430 g C m−2 for NEE, GPP, and Re, respectively. The ratio of Re/GPP in flooded fields was 0.67 while it was 0.83 for aerobic rice fields.This short-term data showed significant differences in C budget and heat exchange between flooded and aerobic rice ecosystems. Further investigation is needed to clarify seasonal and inter-annual variations in microclimate, carbon and water budget of different rice production systems. 相似文献
77.
The n-hexane and ethyl acetate extracts of whole plants of Dysophylla stellata significantly inhibited edema when applied topically at doses of 0.5 and 1 mg/ear in TPA-induced ear edema assay in mice. Further, both the extracts were evaluated for COX-1 and COX-2 inhibitory activities and showed 85.42 and 57.38%; and 71.79 and 89.27% inhibition at 50 µg/ml, respectively. Chromones (1 and 2) present in these extracts could be responsible for their COX-1 and COX-2 inhibitory and anti-inflammatory activities. The ethyl acetate extract showed antioxidant activity in DPPH and ABTS radical scavenging assay where as n-hexane extract found to be inactive. 相似文献
78.
Arvind Kumar 《Phytoparasitica》2014,42(3):295-302
The nature of damage, seasonal incidence, developmental period and morphometrics of Cochlochila bullita (Stål) (Heteroptera: Tingidae) were studied on Ocimum sanctum L. in Jharkhand province of India. The infestation of C. bullita started in June and continued until December on O. sanctum. The highest population of C. bullita per twig was found to be 63.8 in 2011 and 71.2 in 2012, in the months of August and September, respectively. The highest per leaf population of C. bullita was observed in the month of September in both years. The adults and nymphs of C. bullita were found feeding gregariously on the tender leaf and shoot, and laid eggs – mostly single, but sometimes in groups. Pre-oviposition period, oviposition period and egg incubation period of the bug were 3.37, 15.56 and 6.06 days, respectively, whereas the nymphal period was 11.50 days and the adult period was 21.18 days. This is the first report of feeding of C. bullita on O. sanctum from Jharkhand, India. 相似文献
79.
Alok Das Manoj Kumar Arvind Kumar Singh Arpan Alok Shukla Jamal Ansari Subhojit Datta Narendra Pratap Singh 《Journal of Crop Science and Biotechnology》2016,19(4):295-302
Production of transgenic pigeonpea is becoming increasingly important, but the methods currently employed in production and subsequent screening still requires improvement. Here, we describe Agrobacterium-mediated genetic transformation of pigeonpea with reporter uidA (gus) gene and selectable marker, neomycin phospho-transferase (nptII) gene. Histochemical assay demonstrate localization of gus activity in cells and transformed plants. Overall, a transformation frequency of 0.33% was achieved using the protocol. Grafting of in vitro-regenerated healthy shoots indicates higher survival percent (72.6%), when stock and scion are of the same variety. Seeds harvested from primary transgenic plants can be screened based on lateral root inhibition strategy. Approximately 87% of the screened T1 plants were found to be PCR positive. In conclusion, in vitro grafting of transgenic pigeonpea shoots leads to better plant establishment and screening based on lateral root inhibition leads to quick identification of positive segregants. 相似文献
80.
Sanjib K. Behera Arvind K. Shukla M. V. Singh Ravi H. Wanjari Pooja Singh 《Journal of plant nutrition》2015,38(10):1544-1557
Zinc (Zn) deficiency in soils and field crops is widespread across the world, including India, resulting in severe reduction in yield. Hence, soil application of Zn fertilizers is recommended for ameliorating Zn deficiency in soil and for obtaining higher crop yield and better crop quality. Zinc sulfate is commonly used Zn fertilizer in India because of its solubility and less cost. However, good quality and adequate quantity of zinc sulfate is not available in the market round the year for farmers' use. Field experiments were therefore conducted during rainy season of 2010 and 2011 at research farm of Indian Institute of Soil Science, Bhopal, India to assess the influence of Zn application through zinc sulfate monohydrate (33% Zn), zinc polyphosphate (21% Zn) and Zn ethylenediaminetetraacetate (EDTA) (12% Zn) on yield and micronutrient concentration and uptake by maize (Zea mays L.). In both the years, grain and vegetative tissue (stover) yield of maize increased significantly with successive application of Zn up to 1 kg ha?1 added through zinc sulfate monohydrate and zinc polyphosphate. Addition of 2.5 kg Zn ha?1 did not increase yield further but resulted in highest stover Zn concentration. Zinc, copper (Cu), manganese (Mn), and iron (Fe) concentration in maize grain varied from 22.2 to 27.6, 1.6 to 2.5, 3.5 to 4.7 and 19.9 to 24.5 mg kg?1 respectively in both the years. Maize stover had 25.9 to 36.2, 7.9 to 9.8, 36.7 to 44.9 and 174 to 212 mg kg?1 Zn, Cu, Mn, and Fe, respectively. Zinc application did not influence Cu, Mn and Fe concentration in both grain and stover of maize. Transfer coefficients (TCs) of micronutrients varied from 0.72 to 0.95, 0.18 to 0.30, 0.08 to 0.13 and 0.10 to 0.15 for Zn, Cu, Mn, and Fe respectively. Total Zn uptake significantly increased with Zn application from 0.5 to 2.5 kg ha?1 supplied through zinc sulfate monohydrate and zinc polyphosphate. Recovery efficiency of Zn declined with increased Zn rates. 相似文献