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21.
Johnson AL Divers TJ Freckleton ML McKenzie HC Mitchell E Cullen JM McDonough SP 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(6):1414-1421
BACKGROUND: Fourteen horses at a boarding stable in Virginia were diagnosed with hepatic disease and locally grown hay was implicated as the cause. HYPOTHESIS: Panicum dichotomiflorum, the predominant grass species in the hay, is hepatotoxic to horses. ANIMALS: Naturally occurring cases were adult horses of various breeds. Two healthy adult horses and 2 healthy adult sheep were used in feeding trials. METHODS: Blood and liver specimens collected from affected animals during the outbreak were analyzed. Some of the affected animals were treated supportively; the main intervention was hay withdrawal. Feeding trials were not blinded and no treatments were provided. Blood and liver specimens were collected and analyzed throughout the trials. RESULTS: Five affected animals were euthanized, whereas the others recovered. One research horse was euthanized for postmortem examination, and the other research animals recovered after hay withdrawal. All affected animals had evidence of hepatic disease with abnormally high aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP) activity. Evaluation of liver biopsy specimens disclosed mild lymphocytic and histiocytic inflammation, mild vacuolar change (hydropic degeneration), prominently clumped chromatin, and necrosis of individual hepatocytes. CONCLUSIONS AND CLINICAL IMPORTANCE: Severe hepatotoxicosis developed rapidly after Panicum hay exposure. Patchy hepatocyte necrosis was observed, implicating apoptosis as the mechanism of hepatotoxicosis. Absence of fibrosis in the research animals indicates that immediate withdrawal of Panicum hay should allow all but severely affected animals to recover from acute exposure. 相似文献
22.
[目的]确定三七茎基总皂苷含量测定方法,优化其回流提取工艺。[方法]采用香草醛-高氯酸法测定三七茎基总皂苷含量的方法,并以总皂苷含量为指标,优选回流法提取三七茎基总皂苷的工艺条件。[结果]在0.008 3~0.049 6 mg/ml浓度范围内,人参皂苷Rg1浓度与吸光度的线性关系良好(R=0.999 4),平均回收率为99.3%(n=4),RSD为3.4%。最佳提取工艺条件为:料液比1∶10(g/ml)、乙醇浓度60%,浸泡时间12 h,提取3次,每次2 h。[结论]该含量测定方法简便、准确、重现性好;提取工艺经济、合理,值得进一步推广。 相似文献
23.
BACKGROUND: Saponins are a class of secondary plant metabolites consisting of a sugar moiety glycosidically linked to a hydrophobic aglycone (sapogenin) that often possess insecticidal activities. Four saponins were selected: two triterpene saponins, Q. saponaria saponins and aescin, and two steroidal saponins, digitonin and diosgenin. Their effects were investigated on an important pest species and a model piercing‐sucking insect, the pea aphid Acyrthosiphon pisum. The triterpene Q. saponaria saponins bark saponin received special attention because of its high activity. Aphids were challenged by oral and contact exposure to demonstrate aphicidal activities, and in choice experiments to support use as a natural deterrent. RESULTS: When aphids were exposed to supplemented artificial diet for 3 days, a strong aphicidal activity was recorded for three of the four saponins, with an LC50 of 0.55 mg mL?1 for Q. saponaria saponins, 0.62 mg mL?1 for aescin and 0.45 mg mL?1 for digitonin. The LT50 values ranged between 1 and 4 days, depending on the dose. For diosgenin, only low toxicity (14%) was scored for concentrations up to 5 mg mL?1. In choice experiments with treated diet, a deterrence index of 0.97 was scored for Q. saponaria saponins at 1 mg mL?1. In contrast, direct contact showed no repellent effect. Spraying of faba bean plants with Q. saponaria saponins resulted in an LC50 of 8.2 mg mL?1. Finally, histological analysis in aphids fed with Q. saponaria saponins demonstrated strong aberrations of the aphid gut epithelium, and exposure of midgut CF‐203 cell lines to Q. saponaria saponins in vitro confirmed the cytotoxic effect. CONCLUSIONS: The present insect experiments provide strong evidence that saponins, as tested here with triterpene Q. saponaria saponins, can be useful as natural aphicides and deterrents. Furthermore, the insect midgut epithelium is suggested to be a primary target of saponin activity.Copyright © 2011 Society of Chemical Industry 相似文献
24.
Five oleanolic acid triterpenoid saponins (OTS-1, 2, 3, 4 and 5) were isolated from the rhizome of Anemone raddeana. The effect of these triterpenoid saponins on stimulus-induced superoxide generation in human neutrophils was assayed by measuring the reduction of ferricytochrome c using a dual-beam spectrophotometer. The phosphorylation of neutrophil proteins, and translocation of p67(phox), p47(phox) and Rac to plasma membrane were investigated using specific monoclonal antibodies. The five oleanolic acid triterpenoid saponins used in this experiment suppressed N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in a concentration-dependent manner. OTS-1, 2 and 4 suppressed phorbol 12-myristate 13-acetate (PMA)- and arachidonic acid (AA)-induced superoxide generation in a concentration-dependent manner, but OTS-3 and 5 showed no effect. fMLP- and PMA-induced tyrosyl or serine/threonine phosphorylation, and fMLP-, PMA- and AA-induced translocation of p67(phox), p47(phox) and Rac to plasma membrane were in parallel with the suppression of the stimulus-induced superoxide generation. 相似文献
25.
Three new triterpenoid saponins polygalasaponins LI-LIII (1-3) with two acylation groups in oligosaccharide chain, together with three known saponins were isolated from the roots of Polygala japonica Houtt. (4-6). The neuroprotective effects of these compounds on neuron-like PC12 cells were evaluated in vitro. Compounds 5 and 6 show neuroprotective effects in Aβ(25-35) model at the concentration of 10μM. 相似文献
26.
本实验用OVA作为抗原,木鳖子粗皂甙及其经硅胶G分离得到的5个组分(A、B、C、D和E)作为佐剂,免疫ICR雌性小鼠,测定各试验组小鼠抗体效价及抗体亚类。结果表明各组分均有佐剂作用,其活性随流出顺序(A→B→C→D→E)呈递增趋势。 相似文献
27.
Alberto Pea‐Rodríguez Zo Pelletier‐Morreeuw Jazmín García‐Lujn María del Carmen Rodríguez‐Jaramillo Laura Guzmn‐Villanueva Cristina Escobedo‐Fregoso Dariel Tovar‐Ramírez Ana Gisela Reyes 《Aquaculture Research》2020,51(4):1336-1345
Agave lechuguilla is a succulent plant species, mainly distributed in the northeast of Mexico and south of the United States of America. The main use for this plant is the fibre´s extraction (known as Tampico fibres), resulting in 15% of fibres and 85% of a by‐product waste named guishe. The lechuguilla collectors, normally incinerate the guishe, thus causing environmental contamination. Interestingly, recent studies showed that guishe contains molecules with nutritional properties, such as saponins, flavonoids and sugars. Therefore, in this work, we evaluated the effect of the crude extract of guishe as a feed additive in whiteleg shrimp diets. According to that, MS‐HPLC analysis of the extract showed the presence of saponins such as diosgenin, smilagenin, hecogenin, manogenin, tigogenin hexose, yucagenin, chlorogenin, diosgenin diglucoside and the flavonol, quercetin. After chemical analysis, the crude extract was included into an experimental diet in four levels; 0% (L0%), 0.1% (L0.1%), 0.3% (L0.3%) and 0.6% (L0.6%). Dietary incorporation of the extract was evaluated by zootechnical performance, haemolymph biochemistry, histomorphology and digestive enzyme activity of shrimps. After 5‐week feeding, the L0.3% diet showed significantly higher growth and better feed utilization among treatments. A significant increase in tubule epithelium height and tubule coverage area from hepatopancreas in shrimp under L0.3% diet compared with the control diet suggest an improvement of the health and nutritional status of the shrimp. Inclusion of L0.3% and L0.6% of the crude extract resulted in a reduction in amylase activity, without effect in glucose levels in the haemolymph. Thus, we suggest that lechuguilla guishe crude extract contains nutritional molecules that may be used as a feed additive to promote shrimp productivity. 相似文献
28.
黄精总皂苷超声提取工艺研究 总被引:2,自引:0,他引:2
采用水浴加热法、超声法和微波法等3种方法提取黄精总皂苷。结果表明:超声法提取黄精总皂苷方法最佳,具有高效、安全、成本低等优点,且能保护被提取成分不被破坏。采用超声提取,以人参皂苷Rb1标准品为指标,通过正交实验确定最佳提取温度、料液比和提取时间。结果表明:提取温度对黄精总皂苷提取有极显著的影响,提取时间和料液比影响不显著。确定最优提取工艺为:超声提取,80%乙醇提取2次,提取温度60℃,提取时间50 min,料液比1∶15,提取总皂苷含量在3.4%以上。 相似文献
29.
【目的】研究芫根粗总皂苷(ST)对四氧嘧啶所致糖尿病小鼠血糖的影响。【方法】以体积分数 70%乙醇加热提取芫根,并分别以石油醚和正丁醇萃取,得到芫根ST,测定正丁醇萃取相中总皂苷的含量;给昆明小鼠尾静脉注射 85 mg/kg 四氧嘧啶,建立糖尿病小鼠模型;用剂量为 500和1 000 mg/kg的ST对糖尿病小鼠灌胃7 d后,测定初始空腹血糖和最终空腹血糖,并在试验结束时处死小鼠,取胸腺、肝脏、脾脏和肾脏组织称质量计算脏器指数,分析ST对糖尿病小鼠口服耐糖量(OGTT)的改善情况。【结果】正丁醇萃取物中总皂苷的质量分数为(31.5±1.7)%(以薯蓣皂苷元计);ST 500和 1 000 mg/kg灌胃组糖尿病模型小鼠在连续给药7 d后,小鼠血糖显著降低(P<0.05),并且其脏器指数得到了明显改善;500 mg/kg剂量的ST可以显著提高糖尿病模型小鼠的耐糖量。【结论】芫根粗总皂苷可显著降低四氧嘧啶致糖尿病小鼠的血糖。 相似文献
30.
目的考察不同提取方法对西洋参皂苷含量的影响。方法分别选择甲醇、乙醇、水三种不同试剂结合浸泡提取法、回流提取法、超声提取法三种方法提取皂苷,采用高效液相色谱法测定上述不同提取液中Rgl、Re、Rb。的含量。结果人参皂苷Rgl、Re、Rb。在测定范围内具有良好的线性关系。该实验方法可以在相关工作生产中实际应用。不同提取方法中人参皂苷Rbl含量略有影响。结论乙醚脱脂50%乙醇超声提取法中的人参皂苷Rgl和Re含量高于其他提取方法.乙醚脱脂甲醇回流提取法中人参皂苷Rb,含量高于其他提取方法。 相似文献