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1.
Four homoisoflavonoids, 4-O-methylsappanol (1), protosappanin A (2), brazilin (3) and caeasalpin J (4), isolated from Caesalpinia sappan, were tested for inhibitory activity against Beauveria bassiana. Compound 1 showed activity against this fungus.  相似文献   
2.
Survival rate, growth and feed intake were determined for late juveniles (4.31 ± 0.18 g) of river prawn Macrobrachium rosenbergii in freshwater with total ammonia‐N (NH3‐N+NH4‐N) concentrations of 0.015 (control), 0.5, 1.0 and 1.5 mg L−1 for 60 days at pH 7.53 ± 0.04 and temperature 24.0 ± 2.5°C. Survival rate was significantly (P<0.05) lower (54 ± 4.2–70 ± 5.4%) for total ammonia concentrations from 0.5 to 1.5 mg L−1 [0.0139–0.0419 mg L−1 of unionized ammonia (NH3)]. Growth (0.026–0.030 g day−1 range) of the prawns did not differ for the different NH3 levels but were significantly (P<0.05) lower compared with control (0.056 g day−1). Feed intake rates also diminished significantly (P<0.05) from 77.60 ± 2.45% at control (0.015 mg L−1 NH3‐N) to 48.69 ± 2.13% at 1.5 mg L−1 NH3‐N (0.0419 mg L−1 of unionized NH3).  相似文献   
3.
A safe and simple thin layer chromatographic method has been developed for the estimation of niacin and niacinamide in pharmaceutical preparations containing other vitamins, enzymes, herbs, antiamoebic drugs, etc. The method involves removal of excipients from the preparation by ethanol precipitation and isolation of niacin or niacinamide from other ingredients by TLC on silica gel with water as developing solvent, followed by extraction in 0.1N HCl, and spectrophotometric estimation of the vitamin at 262 nm. The percent recoveries for niacin and niacinamide were 100.1 +/- 1.9 and 100.2 +/- 1.5, respectively.  相似文献   
4.
Hoki (Johnius belengerii) skin gelatin was hydrolyzed with three commercial enzymes to identify radical-scavenging potencies of derived peptides. Peptides derived from tryptic hydrolysate exhibited the highest scavenging activities on superoxide, carbon-centered 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals assessed by ESR spectroscopy. Following consecutive chromatographic separations of tryptic hydroolysate, the peptide sequence His-Gly-Pro-Leu-Gly-Pro-Leu (797 Da) acted as a strong radical scavenger under studied conditions. Further, this peptide could act as an antioxidant against linoleic acid peroxidation and the activity was closer to the highly active synthetic antioxidant butylated hydroxytoluene (BHT). In addition, antioxidative enzyme levels in cultured human hepatoma cells were increased in the presence of this peptide and it was presumed to be the peptide involved in maintaining the redox balance in the cell environment. Present data indicate that free-radical-scavenging activities of hoki skin gelatin peptides substantially contribute to their antioxidant properties measured in different oxidative systems.  相似文献   
5.
The effects of extender composition, cryoprotectant concentration and freezing and thawing on the fertilization efficiency of cryopreserved spermatozoa of Puntius gonionotus were evaluated. Computer‐aided motility analysis of semen was conducted to check the suitability of spermatozoa for cryopreservation after mixing with different extenders and cryoprotective agents (CPAs). Extender‐4 with an osmolality 260 mOsmol kg−1and pH 7.6 was used for the cryopreservation study. Among the CPAs, dimethyl sulphoxide (DMSO) was least toxic and more than 60% fertilization was achieved when used at 1.4 M at 0 °C for 10 and 30 min, whereas the toxicity of all CPAs to spermatozoa was evident when tested at 30 °C. Semen frozen at −16 °C min−1 with 1.4 M DMSO showed 70% fertilization, which was significantly higher (P<0.05) than other freezing rates. Samples thawed at 35 °C water showed a fertilization rate comparable with that of fresh semen. Computer‐assisted semen analysis of fresh and frozen semen after thawing showed variations in different types of motility in spermatozoa and in their class. There was no significant difference in motility before or after cryopreservation; however, significant differences could be observed in the average path velocity (VAP), straight line velocity (VSL) and curve linear velocity (VCL). Semen of silver barb could be cryopreserved with extender‐4 by addition of 1.4 M DMSO to a final cryopreservation medium (MED 2) cooled at a rate of −16 °C min−1, stored in liquid nitrogen (−196 °C) and utilized after thawing at 35±2 °C.  相似文献   
6.
The aim of this study was to evaluate the dietary dosages of turmeric that enhance immune response and disease resistance against the opportunistic pathogens Aeromonas hydrophila in Labeo rohita fingerlings. Hence, four different dosages of turmeric at 0.1, 0.5, 1.0 and 5.0 g kg?1 feed were given to the fingerlings of L. rohita for 60 days at 4% body weight. At every 20‐day interval, different biochemical, haematological, enzymatic and immunological parameters of fish were evaluated. After 60 days, fish were challenged with A. hydrophila. The mortality (%) was recorded on the tenth day post challenge. Most of the immune parameters including lysozyme activity, superoxide anion production and serum bactericidal activity were significantly (P<0.05) higher on 60 days of feeding of 1.0 g of turmeric per kg of feed. Challenge study indicated 100% and 89% survivability in the group of fish fed with 5.0 and 1.0 g of turmeric per kg of feed respectively. Feeding of turmeric might have maintained long‐term protection in fish by elevating the nonspecific immune system such as Nitroblue tetrazolium (NBT), lysozyme and serum bactericidal activity. The result showed that turmeric at a dose of 1.0 g kg?1 feed for 60 days provided the greatest protection to pathogen challenge.  相似文献   
7.
In an attempt to find a suitable alternative to the otherwise perilous chemical control strategy of disease management, the amino acid proline was evaluated for its efficiency to elicit resistance in pearl millet (Pennisetum glaucum (L.) R. Br.) against downy mildew disease caused bySclerospora graminicola (Sacc.) Schroet both under greenhouse and field conditions. Proline treatment to seeds at 50 mM concentration for 3 h, significantly enhanced the seed germination and seedling vigor of pearl millet in comparison with the control. The same concentration and duration of seed treatment protected the pearl millet plants from downy mildew by offering 58% protection under greenhouse and 67% protection under field conditions. Studies revealed that 3 days were required for proline-treated plants to develop resistance, which was systemic and was sustained throughout the life of the plants. Apart from disease protection, proline was also found effective in enhancing vegetative and reproductive growth of the plants, as evidenced by the increase in height, fresh weight, leaf area, tillering capacity, 1000-seed weight and grain yield in comparison with the control plants. http://www.phytoparasitica.org posting Oct. 3, 2004.  相似文献   
8.
The present study was conducted to evaluate two Indian native chicken breeds, namely, Aseel and Kadaknath for fertility, hatchability, genetic parameters of juvenile growth traits, and semen quality traits at the onset of sexual maturity. The fertility was similar in Aseel (86.96%) and Kadaknath (85.15%); however, a relatively higher hatchability was observed in Kadaknath (77.94%) than Aseel (70.74%). Heritability estimates of body weights at 4 weeks of age were almost similar in Aseel (0.37) and Kadaknath (0.39), while the estimate of body weight at 6 weeks of age was higher in Aseel (0.42) than Kadaknath (0.31). The heritability estimate of shank length at 6 weeks of age was lower in Aseel (0.16) compared to Kadaknath (0.35). The age at first egg in the flock was comparable in Aseel (148 days) and Kadaknath (150 days). Aseel breed with significantly (P ≤ 0.001) higher body weight, absolute and relative testes weights had significantly higher semen volume (P ≤ 0.05) and sperm motility (P ≤ 0.01) but had lower seminal plasma cholesterol level (P ≤ 0.05) as compared to Kadaknath. It can be concluded that there is a scope for genetic improvement of these two native breeds for juvenile growth traits since heritability estimates of these traits were relatively high.  相似文献   
9.
Estimation of sediment load from Himalayan basins is of considerable importance for the planning, designing, installation and operation of hydro-power projects, including management of reservoirs. In the present study, an assessment of physical and chemical load, sediment yield and erosion rate has been undertaken at eight different locations in the Sainj and Tirthan watersheds. The analysis revealed that the maximum load was transferred during the monsoon season. Moreover, the estimated average chemical erosion rate of the Sainj (83 t km− 2 yr− 1) and Tirthan (80 t km− 2 yr− 1) watersheds were higher than that of the Indian average (69 t km− 2 yr− 1) representing all the rivers. Both watersheds were eroding physically and chemically at a faster rate than that of the world global average erosion rate (185 t km− 2 yr− 1). The flattish nature of the channels in some segments of these watersheds showed a lower transport of sediments, where as the constricted segments having steep bed slopes increased the velocity of flow and the sediment transport rate. These findings have important implications for water resource management in the context of sediments mobilization, erosion, channel management, ecological functions and operation of the hydro-power projects in the Lesser Himalayan region.  相似文献   
10.
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