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1.
Chitra M  Devi CS  Sukumar E 《Fitoterapia》2003,74(4):401-403
Embelin, a benzoquinone-derivative isolated from Embelia ribes, when tested for its antibacterial potential exhibited significant inhibition against five and moderate activity against three strains of the 12 bacteria tested.  相似文献   
2.
Hashim MS  Devi KS 《Fitoterapia》2003,74(7-8):670-676
Extracts from the stem bark of Streblus asper possess insecticidal activity against the fifth instar of Dysdercus cingulatus. Methanolic extract showed an LC(50) value of 5.56 microg/insect. Partition with chloroform increased the insecticidal activity (LC(50) 2.01 microg/insect). Three polyphenolic rich fractions were obtained from silica-gel column chromatography of the chloroform fraction and found to have noteworthy insecticidal activity (LC(50): 1.82 microg, 2.70 microg, 2.26 microg/insect) by topical application. This may provide a useful beginning for the development of biopesticides.  相似文献   
3.
The current study is based on the screening of novel insecticides from new sources that have not being exploited hitherto. The major objectives of this research work were to extract marine molluscs, Lambis lambis, Trochus radiatus and Chicoreus ramosus, from Tuticorin coastal waters using different solvents to test their insecticidal properties and partially purify the active components. The ethyl acetate extracts of L. lambis and T. radiatus showed 100% mortality of Sitophilus oryzae, at a concentration of 200 μg ml−1. The LC50 values for ethyl acetate extracts of L. lambis, T. radiatus and C. ramosus were found to be 67.08, 348.86 and 571.42 μg ml−1, respectively. With regard to bacterial metabolites, at a concentration of 200 μg ml−1 the ethyl acetate extract of A3 was able to elicit an activity of 40% and that of strain A1 – 20%. The LC50 values of the bacterial metabolites were also investigated. Upon chromatographic separation of active ethyl acetate extracts of T. radiatus, the 100% methanol column-purified fraction was found to have an activity of 30% at a concentration of 10 μg against S. oryzae. The purity of the partially pure active compound was observed to be 72.78% on analysis with high pressure thin layer chromatography.  相似文献   
4.
We examined the carbon stock and rate of carbon sequestration in a tropical deciduous forest dominated by Dipterocarpus tuberculatus in Manipur,North East India.Estimation of aboveground biomass was determined by harvest method and multiplied with density of tree species.The aboveground biomass was between18.27–21.922 t ha-1and the carbon stock ranged from9.13 to 10.96 t C ha-1across forest stands.Aboveground biomass and carbon stock increased with the increase in tree girth.The rate of carbon sequestration varied from1.4722 to 4.64136 t ha-1year-1among the dominant tree species in forest stands in tropical deciduous forest area.The rate of carbon sequestration depends on species composition,the density of large trees in different girth classes,and anthropogenic disturbances in the present forest ecosystem.Further work is required to identify tree species having the highest potential to sequester CO2 from the atmosphere,which could lead to recommendations for tree plantations in a degraded ecosystem.  相似文献   
5.
Bandyopadhyay  S.  Mandal  S.  Datta  K. K.  Devi  P.  De  S.  Bera  A. K.  Bhattacharya  D. 《Tropical animal health and production》2010,42(7):1481-1486
Gastrointestinal parasitic infection is highly prevalent in the North Eastern States (NEH) of India and accounted for significant economic losses across various livestock species. Productivity of cattle in terms of milk yield was estimated to be considerably higher (3,715, 3,590, and 3,154 L) due to strategic anthelmintic treatment as compare to control group (2,928 L). Based on the probability of occurrence of parasitic infection as well as increase in value of milk production, the possible economic gain at state level has been estimated to be Rs. 46 million, Rs. 35 million, and Rs. 14 million, depending upon the different strategic treatment. The government may take up the program to educate the cattle farmers on strategic management against parasitic infecion and simultaneously making available various anthelmintic medicines. This public responsibility of the government to minimize the risk and economic loss due to gastrointestinal parasite infection may reduce the private cost and thereby would increase the social benefits in North Eastern states of India.  相似文献   
6.
The purpose of our study was to investigate changes in immunological parameters induced by weaning stress (including milk restriction) in calves. Fifteen Holstein calves were subjected to weaning at 6 weeks of age. Blood samples were collected at -14, -7, -2, 1, 3, and 5 days post-weaning (DPW; 0 DPW = 42 days). Weaning caused significant (p < 0.01) increases in the neutrophil (NE):lymphocyte (LY) ratio at 5 DPW with a significant (p < 0.05) reduction of LYs. The concentration of acute-phase proteins (haptoglobin and serum amyloid A) also increased significantly (p < 0.05) at 3 and 5 DPW compared to -2 DPW. Levels of the iron-binding protein lactoferrin decreased significantly (p < 0.05) after weaning. Serum tumor necrosis factor-α and cortisol levels were elevated (p < 0.05) at 3 DPW, while those of serum interferon-γ decreased (p < 0.05) at 1 and 3 DPW compared to levels observed before weaning. Weaning significantly (p < 0.05) decreased the percentage of CD25+ T cells in the peripheral blood. In conclusion, weaning stress affected the NE:LY ratio along with the levels of acute phase proteins, lactoferrin, cortisol, and inflammatory cytokines in the peripheral blood of calves. Weaning stress may induce an acute phase response possibly through the elevation of cortisol production and modulation of inflammatory cytokines.  相似文献   
7.
杂交水稻Le/Qi在施基肥基础上始穗期追施N,NK营养比其亲本和仅施基肥(NPK)表现剑叶叶绿素(a+b)总量及可溶性蛋白含量多,SPS酶活性及SPS/F-1,6-Pase的酶活性比率高,14C-蔗糖同化物从顶3叶及叶鞘的输出率亦高,剑叶含矿质营养K,Ca,Mn,Mg及Fe也较高。Le/Qi从抽穗期至蜡熟期残留在叶鞘及茎中的可溶性糖及淀粉的量较少,蜡熟期被分配到穗部的量较多,且与谷产量分别呈极显著及显著正相关,谷产量比Lemont(母本)高约32%,比七挂早(父本)高8%,而光合速率则处于亲本之间,偏于母本。  相似文献   
8.
The protein quality of algaeSpirulina platensis was evaluated biochemically in adult albino rats by serum protein regeneration studies. Rats depleted for 12 days were repleted for 15 days with diets containing 10% protein derived from algae, methionine supplemented algae, or casein. On protein depletion, the activity of the hepatic enzymes, succinic dehydrogenase and alanine aminotransferase, were lowered while the activity of alkaline phosphatase increased. Protein repletion with algal and casein diets resulted in an increased activity of succinic dehydrogenase and alanine amino transferase and a decrease in alkaline phosphatase activity. However, the levels of these three enzymes were lower with the algal than with the casein diets. Algal diets regenerated serum protein effectively though to a slightly lesser extent than casein.  相似文献   
9.
10.
Effect of combinations of millet and legume and processing on digestibility, biological value and net protein utilization was evaluated using albino rats. The millets and legumes selected for the study include sorghum, pearl millet, finger millet, chickpea and green gram (P radiatus). The processes tested include dehulling, boiling, roasting, malting and baking. Among the combinations tested, the sorghum-chickpea combination had significantly (p<0.05) higher digestibility. Between the processes tested, roasting resulted in significantly higher net protein utilization. Results of biological study on biscuits prepared by using millet and legume combination flours, indicated the biscuits to be of good protein quality.  相似文献   
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