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81.
Anti-inflammatory activity of (+)-usnic acid.   总被引:5,自引:0,他引:5  
(+)-Usnic acid, isolated from the lichen Roccella montagnei, showed a dose-dependent anti-inflammatory activity when tested on rats, employing acute and chronic models.  相似文献   
82.
Understanding biodiversity and community composition is a prerequisite to sustainable exploitation and conservation of fisheries. We assessed the spatial and seasonal patterns of fish community composition and biodiversity in seasonal no-take riverine sanctuaries in Bangladesh, which aim to conserve the anadromous hilsa shad (Tenualosa spp. and Hilsa keele). Fish samples were collected during monsoon, as well as pre- and postmonsoon, from five sites within two sanctuaries and one site in an open fishing area. Although total abundance was similar along the rivers, species richness was significantly higher at the open fishing site due to its connectivity to nearby habitats. The diversity apparently decreased in a downstream direction. Fish communities at two upstream sites were separated from other sites in multivariate space largely due to higher abundance of hilsa at downstream sites and presence of floodplain-oriented species at the two upstream sites. Short body length and high trophic level at all sites indicated that fish communities were overexploited. Our results also indicated that riverine hilsa sanctuaries in Bangladesh are rich in fish species diversity and support several threatened species designated by the International Union for Conservation of Nature (IUCN). Our study also suggested that since hilsa abundance shapes community patterns, it can therefore impact riverine ecosystem functioning in the sanctuary areas. The findings of this study can serve as an important baseline for future biodiversity assessment, conservation and impact assessment of conservation in rivers, and therefore help to establish multispecies ecosystem-based management of riverine fisheries around the world.  相似文献   
83.
Serum electrolytes, minerals, blood biochemical and plasma enzymes were studied in heat exposed buffalo heifers supplemented with yeast powder in feed to alleviate the adverse effects of heat stress. Eighteen healthy Murrah buffalo heifers (270-280) kg were divided into three groups. Animals of group I were kept in shed and served as control, while group II and group III were exposed in a psychrometric chamber at 40°C for 4?hrs daily for 16?days continuously. The animals in group III were also supplemented with yeast powder at 10?g per animal per day. The serum sodium, potassium and chloride levels decreased significantly (P?相似文献   
84.
The aim of the study was to determine the effect of feeding feed blocks containing varying proportion of urea-treated paddy straw (UTPS) on dry matter (DM) intake (DMI), nutrient utilization and N balance in Mithun. For the purpose, four adult male Mithun (279.5 ± 8.2 kg) were selected and offered four experimental rations viz. R1 (Napier fodder + concentrate at 60:40), R2 (UTPS + concentrate at 50:50), R3 (UTPS + concentrate at 60:40) and R4 (UTPS + concentrate at 70:30) in 4 × 4 Latin square design. The DMI % of body weight was 2.59, 2.96, 2.85 and 2.77 and the DMI g kg−1 W0.75 was 107, 123, 118 and 115 in Mithun fed R1, R2, R3 and R4, respectively. The mean DMI was (P < 0.01) higher in animals fed R2 and R3 than R1 and R4, whereas the water intake was (P < 0.01) higher in Mithun fed R2, R3 and R4 than R1. The digestibility of DM, organic matter, crude protein, crude fibre, neutral detergent fibre and cellulose were (P < 0.05) higher in animals fed R2, R3 and R4 than R1. A positive N balance was observed in all the experimental animals, with higher (P < 0.05) values among the animals offered R2, R3 and R4 than R1. The digestible crude protein and total digestible nutrient intakes were higher (P < 0.05) in Mithun fed R2 and R3 than R1 and R4. It is concluded that the UTPS can be incorporated up to 70% to formulate the complete feed/feed block and can be used for feeding of Mithun under complete confinement system.  相似文献   
85.
Latex of the medicinal plant Ervatamia coronaria was found to contain at least three cysteine proteases with high proteolytic activity, called ervatamins. One of these proteases, named ervatamin B, has been purified to homogeneity using ion-exchange chromatography and crystallization. The molecular mass of the enzyme was estimated to be 26 000 Da by SDS-PAGE and gel filtration. The extinction coefficient (epsilon(1%)(280 nm)) of the enzyme was 20.5 with 7 tryptophan and 10 tyrosine residues per molecule. The enzyme hydrolyzed denatured natural substrates such as casein, azoalbumin, and azocasein with a high specific activity. In addition, it showed amidolytic activity toward N-succinyl-alanine-alanine-alanine-p-nitroanilide with an apparent K(m) and K(cat) of 6.6 +/- 0.5 mM and 1.87 x 10(2) s(-)(1), respectively. The pH optima was 6.0-6.5 with azocasein as substrate and 7.0-7.5 with azoalbumin as substrate. The temperature optimum was around 50-55 degrees C. The enzyme was basic with an isoelectric point of 9.35 and had no carbohydrate content. Both the proteolytic and amidolytic activity of the enzyme was strongly inhibited by thiol-specific inhibitors. Interestingly, the enzyme had only two disulfide bridges versus three as in most plant cysteine proteases of the papain superfamily. The enzyme was relatively stable toward pH, denaturants, temperature, and organic solvents. Polyclonal antibodies raised against the pure enzyme gave a single precipitin line in Ouchterlony's double immunodiffusion and typical color in ELISA. Other related proteases do not cross-react with the antisera to ervatamin B showing that the enzyme is immunologically distinct. The N-terminal sequence showed conserved amino acid residues and considerable similarity to typical plant cysteine proteases.  相似文献   
86.
Abstract

An experiment was conducted to substitute mineral fertilizers with biofertilizers in strawberry to work out the yield, quality of strawberry and soil fertility. A 25% substitution of mineral fertilizer with biofertilizer increased the number of fruits/plant along with improving Juice content (89.55%), Total soluble solids (10.35°B), total sugar (6.69%), ascorbic acid (43.80?mg 100?g?1), anthocyanin content (81.05?mg 100?g?1), total phenol (5.97?mg Gallic acid equiv. g?1), flavonoids (0.12?mg g?1) and antioxidant capacity (2.13?µmol. Trolox equiv. 100?g?1). The available N and K content in post-harvest soils were improved significantly with 75% RDF + Azospirillium @ 2?g plant?1 + PSB @ 2?g plant?1 + topdressing of 25% K treatments (200.10 and 211.70?kg ha?1, respectively). Viable count of soil microorganisms (Bacteria, actinomycetes and fungi) was also estimated maximum (4066, 190 and 11.33?×?104 cfu g?1?dry soil, respectively) with substitution of 25% of mineral fertilizer either with Azotobacter or Azospirillum.  相似文献   
87.
A long-term field experiment was conducted in Vertisols of Solapur (Maharashtra, India) to assess the effect of the integrated use of nutrients on yield, soil properties, and nutrient balance in post-monsoon sorghum. The highest crop yield (1.19 Mg ha?1) and available nutrients (308, 14.9, and 814 kg ha?1 nitrogen (N), phosphorus (P), and potassium (K), respectively) were recorded in the treatment of 25 kg N sorghum crop residue (CR) + 25 kg N Leucaena clippings (LCs), 25 kg N (CR) + 25 kg N (urea), 25 kg N farmyard manure + 25 kg N (urea), and 25 kg N (CR) + 25 kg N (LC), respectively. Most of the nutrients were depleted except K and Ca. The response ratio for N (16 kg kg?1) and partial factor productivity (33 kg kg?1) were considerably higher in the 25 kg N (CR) + 25 kg N (LC) treatment. Conjunctive use of organic ?and chemical fertilizers helped in reducing the nutrient losses and improved their use efficiency and yield sustainability.  相似文献   
88.
Polyploid breeding is an effective tool to induce variability in the existing population, specifically in the crops having very narrow genetic base such as acid lime. Hence, an experiment was conducted to induce polyploidy in acid lime through colchicine treatment. Higher frequency of triploids were obtained in 250 μM colchicine treatment (27.27%), whereas combination of 3× (21.42%), 4× (13.33%) and aneuploid (6.67%) were induced at 500 μM colchicine treatment. Measurement of stomatal density and guard cell size of colchiploids revealed that the former one has negative relation with ploidy level and a positive relation was observed between guard cell size and ploidy level. Further, area and size of nuclei also had a positive relation with ploidy level. Hence, stomatal density, guard cell and nuclei size can be used effectively as morphological marker for preliminary polyploid screening. From the experiment, it can be concluded that 500 μM colchicine treatment of in vitro derived shoot tip explants of acid lime is optimum for creating maximum possible variability through polyploidization in the existing acid lime population.  相似文献   
89.
In India, zinc (Zn) has been recognized as the fourth most important yield-limiting nutrient after nitrogen (N), phosphorus (P) and potassium (K). Supplementing the zinc (Zn) requirement of agricultural crops through water soluble zinc sulfate ZnSO4 fertilizer is a costly management option whereas, utilization of ZnO (water insoluble and a cheaper material) as a source of Zn could be an alternative cost effective option to encourage farmers for wider adoption. In this present investigation, in order to supply the requisite amount of Zn to the plants, a protocol has been developed to coat the seeds of maize (Zea mays L.), soybean (Glycine max L.), pigeon pea (Cajanas cajan L.) and ladies finger (Abelmoschus esculentus L.) with microns scale (<3 µm) and nano-scale (<100 nm) ZnO powder at 25 mg Zn/g seed and at 50 mg Zn/g seed. Different Zn sources, ethyl alcohol, and crude pine oleoresin (POR) were used for coating of seeds. The germination test carried out with coated and uncoated seeds indicated better germination percentage (93–100%) due to ZnO coating as compared to uncoated seeds (80%). Pot culture experiment conducted with coated seeds also revealed that the crop growth with ZnO coated seeds were similar to that observed with soluble Zn treatment applied as zinc sulfate heptahydrate (ZnSO4·7H2O) (at 2.5 ppm Zn) which is evident from the periodic SPAD reading taken after 20, 25, 30 and 45 days after sowing. Application of Zn through different sources also enhanced the auxin indole-3-acetic acid (IAA) production in plant roots, which subsequently improved the overall growth. The most important advantage of seed coating with ZnO (both micron/nano-scale) is that it did not exert any osmotic potential at the time of germination of the seed, thus, the total requirement of Zn of the crop can be loaded with the seed effectively through nano-scale ZnO particle.  相似文献   
90.
A five-week experiment was conducted to delineate stress-mitigating effects of three different methyl donors in Labeo rohita fingerlings subjected to endosulfan toxicity. Four iso-nitrogenous and iso-caloric feed were prepared with and without supplementation of methyl donors. The feed were basal or control diet (i.e., without methyl donor supplementation), feed supplemented with choline, feed supplemented with betaine and feed supplemented with lecithin. Two hundred and twenty-five fishes were distributed randomly in five treatment groups each with three replicates. The experimental setup were normal water (without endosulfan) and fed with control diet (control group), endosulfan-treated water and fed with control diet (T?), endosulfan-treated water and fed with choline supplemented feed (T?), endosulfan-treated water and fed with betaine supplemented feed (T?) and endosulfan-treated water and fed with lecithin-supplemented feed (T?). The level of endosulfan in endosulfan treated water was maintained at the level of 1/10 of LC??, that is, 0.2 ppb. During the experiment, growth performances, metabolic enzyme activity and histological examination were done to assess the effect of treatments. The growth performance (percentage weight gain, feed conversion ratio, specific growth rate and protein efficiency ratio) and nutrient digestibility were significantly different (P<0.01) in lecithin, betaine and choline fed group when compared to endosulfan-exposed group fed with basal diet. The liver LDH and MDH activity were significantly (P<0.01) improved in the groups fed with methyl donor supplemented diet. The liver AST and ALT, brain AChE and muscle ALT did not change with supplementation in the diet, but muscle ALT and G6PDH significantly (P<0.01) changed with supplementation. The gill and liver ATPase and intestinal ALP were significantly (P<0.01) noticeably changed in supplemented group. After endosulfan exposure, histopathology alter like slight large vacuolation in hepatocyte and lipoid vacuole were observed and with supplementation normal appearance of liver were observed. The chromosome aberration (karyotype) was observed in endosulfan-exposed group. The result obtained in present study concluded that inclusion of methyl donors, particularly lecithin and betaine, in feed as nutritional supplements has a potential stress-mitigating effect in L. rohita fingerlings.  相似文献   
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