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1.
为研究安络小皮伞提取物对运动外伤的镇痛作用,对其所含生物碱、多糖和麦角甾醇类等物质进行了定性检测并进行了小鼠醋酸扭体和小鼠热板镇痛试验。结果表明,安络小皮伞提取物中含有的成分能够消除并缓解小鼠各种神经疼痛,具有抗炎镇痛的功效。 相似文献
2.
为评价新兽药"芪蓝饮"及其不同提取成分的体外抗病毒活性,本试验通过细胞病变抑制法和MTT比色法检测了各提取成分对新城疫病毒(NDV)感染鸡胚成纤维细胞(CEF)过程的影响。结果显示,在3种加药方式中"芪蓝饮"原药(QLY)直接杀灭NDV的作用最强,其抑制率最高为128.85%;原药总多糖(TPS)干扰NDV的增殖作用最强,其抑制率最高为130.23%;原药总萜类(TT)直接杀灭NDV的作用最强,其抑制率最高为146.15%;板蓝根总生物碱(RIA)及其水溶性部位(RIAw)和酸性部位(RIAa)对抗NDV的方式是多环节的。综上所述,"芪蓝饮"及其提取成分表现出较强的干扰NDV增殖和直接杀灭NDV的作用,而阻断作用稍弱。 相似文献
3.
Sorghum ergot produces dihydroergosine (DHES) and related alkaloids, which cause hyperthermia in cattle. Proportions of infected panicles (grain heads), leaves and stems were determined in two forage sorghum crops extensively infected 2 to 4 weeks prior to sampling and the panicles were assayed for DHES. Composite samples from each crop, plus a third grain variety crop, were coarsely chopped and half of each sealed in plastic buckets for 6 weeks to simulate ensilation. The worst-infected panicles contained up to 55 mg DHES/kg, but dilution reduced average concentrations of DHES in crops to approximately 1 mg/kg, a relatively safe level for cattle. Ensilation significantly (P = 0.043) reduced mean DHES concentrations from 0.85 to 0.46 mg/kg. 相似文献
4.
植物源农药中生物碱提取和纯化技术进展 总被引:3,自引:0,他引:3
生物碱是广泛存在于植物中的碱性含氮化合物,一些生物碱因其具有一定的防治病虫害等作用,成为近年来研究的热点。为了使生物碱提取率和纯度不断提高,生物碱的提取与纯化技术也在不断地改进与发展。本文综述了近年来植物源农药中生物碱在提取和纯化新技术的进展,并分析探讨新技术原理、优缺点以及发展前景。 相似文献
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6.
Perennial ryegrass (Lolium perenne L.) infected with a novel endophyte (AR37 or AR1), Wild‐type endophyte or no endophyte (Nil) was sown with white clover (Trifolium repens L.) in autumn 2005. The pastures were rotationally grazed by dairy cows from 2005–2009. Annual dry matter (DM) yield did not differ but AR37 pastures had a higher ryegrass tiller density, especially after the 2008 summer drought (+130%), and less white clover than did AR1 pastures. Concentrations of alkaloids produced by the Wild‐type association (lolitrem B, ergovaline) followed the same seasonal trends as did the AR37 alkaloids (epoxy‐janthitrems) but summer drought reduced concentrations of lolitrem B and epoxy‐janthitrems to less than half the mid‐summer (February) peak concentrations in the other years. Insect pests were monitored annually between 2006 and 2009. Tiller damage by Argentine stem weevil (Listronotus bonariensis (Kuschel)) was significantly reduced by all endophyte treatments. African black beetle (Heteronychus arator (F.)) populations in soil samples increased during the experiment with Nil > AR1 > Wild‐type = AR37. Root aphid (Aploneura lentisci (Pass.)) infestations followed the pattern AR1 > Nil > Wild‐type = AR37. A lower pest pressure from all insect pests in AR37 pastures is likely to have contributed to this treatment having the highest ryegrass tiller densities. 相似文献
7.
Tanja Grkovic Johanna S. Blees Magdalena M. Bayer Nancy H. Colburn Cheryl L. Thomas Curtis J. Henrich Megan L. Peach James B. McMahon Tobias Schmid Kirk R. Gustafson 《Marine drugs》2014,12(8):4593-4601
A cell-based high-throughput screen that assessed the cellular stability of a tumor suppressor protein PDCD4 (Programmed cell death 4) was used to identify a new guanidine-containing marine alkaloid mirabilin K (3), as well as the known compounds mirabilin G (1) and netamine M (2). The structures of these tricyclic guanidine alkaloids were established from extensive spectroscopic analyses. Compounds 1 and 2 inhibited cellular degradation of PDCD4 with EC50 values of 1.8 μg/mL and 2.8 μg/mL, respectively. Mirabilin G (1) and netamine M (2) are the first marine natural products reported to stabilize PDCD4 under tumor promoting conditions. 相似文献
8.
Alkaloid Accumulation in Catharanthus roseus Increases with Addition of Seawater Salts to the Nutrient Solution 总被引:1,自引:0,他引:1
WANG Jing-Yan LIU Zhao-Pu College of Resources Environmental Sciences Nanjing Agricultural University Nanjing 《土壤圈》2010,(6)
A sand culture experiment was conducted to determine the effects of different seawater (5% and 10%) treatments on plant growth,inorganic ions,indole alkaloid concentrations and yields of Catharanthus roseus,in an effort to increase the alkaloid yield by artificial cultivation.The total fresh and dry weights and tissue K + concentrations decreased,but Na + concentrations increased in the plant roots,stems and leaves of C.roseus under seawater stress as compared to the control.The concentrations and yields of... 相似文献
9.
In harmony with international regulations the creation of poppy cultivars with high alkaloid content as well as free of alkaloids is in progress. In the course of selection procedures, five poppy cultivars of high chemical diversity, ‘Kheops’, ‘AT, ‘Tebona’, ‘Kék Gemona’ and ‘Przemko’, were selfed and crossed in two successive years (2000‐01). After full ripening, both the biomass production and the alkaloid content of capsules of selfed and crossed plants were determined. When the castrated alkaloid‐free cultivar ‘Przemko’ (accumulating only 0.01 mg/100 g morphine in capsules) was pollinated with cultivars rich in alkaloids, the morphine content of its capsules increased to 0.9‐7.5 mg/100 g‐values. Based on the well‐known biosynthetic background of poppy alkaloids, this can be explained by promotion of (S)‐norcoclaurine synthesis, which seems to be suppressed in alkaloid‐free plants; but tissues of the developing hybrid seeds, which contain a combined gene pool of both alkaloid‐free cultivar and that of the pollen donor plants, release this suppression. The chemical metaxenia also manifested itself in other combinations. In particular, the appearance of narcotine (0.1‐1.1 mg/100 g) in the narcotine‐free cultivars ‘Kheops’, ‘A1’ and ‘Przemko’ can be explained biochemically. If the narcotine‐type plants ‘Kék Gemona’ (accumulating 11.3 mg/g narcotine) were used for pollination, the developing seed tissue, which contains the gene pool of narcotine biosynthesis, might contribute to the suppression of the activity of 1,2‐dehydroreticuline reductase, which leads to the accumulation of narcotine at the cost of morphinanes. 相似文献
10.
Summary A new mutant allele, described here as mutal, which reduces the alkaloid content in dry matter of lupinus mutabilis has been identified following seed treatment with ethyl methane sulphanate. The allele, when homozygous, reduces the alkaloid content from levels of > 2.0 per cent found in seed dry matter of existing populations to 0.2–0.3 per cent and produces plants with vegetative and seed tissues that are organoleptically sweet. Component alkaloids in plants homozygous for mutal differ in respect of the percentage composition of sparteine and of lupanine, as well as possibly of oxa-sparteine and 4-hydroxylupanine, but none is eliminated in genotypes homozygous for the mutant allele. Alkaloid concentration, in so far as not under the control of mutal, has low heritability but lines were isolated following two generations of successive selection which possessed reduced alkaloid levels. These were interpreted to have arisen as a result of recombination of alleles affecting reduction in alkaloid level at several loci. the mutant, mutal, has been established in a pure breeding line which represents a crucial additional step in the evolution of Lupinus mutabilis towards full status as a crop plant. 相似文献