红车轴草有效成分的研究进展

对红车轴草的化学成分、药理作用的研究概况作一综述。     

Anticestodal Activity of Trifolium repens. Extract

ABSTRACT

Trifolium repens. L. is an herbal plant that is used in the folk medicine of the Naga tribes of India as a deworming remedy. This study deals with evaluating its anticestodal activity using experimental Hymenolepis diminuta. Rudolphi infections in albino rats. Doses of T. repens. aerial shoots extract 200 and 500?mg/kg reduced the mean fecal egg counts of H. diminuta. by 47.72% and 54.59% and worm recovery rate by 60.00% and 40.00%, respectively. Praziquantel, the standard cestocidal drug, reduced the mean fecal egg count by 65.90% and worm recovery rate by 26.67%. The study suggests that the aerial shoots of T. repens. bear anticestodal properties and supports its use in the traditional medicine system.     

The isoflavones mixture from Trifolium pratense L. protects HCN 1-A neurons from oxidative stress

Oxidative stress-induced neuronal cell death has been implicated in different neurological disorders and neurodegenerative diseases such as Alzheimer's disease and Parkinson's. Using the Alzheimer's disease-associated hydrogen peroxide (H(2)O(2)), we investigated the neuroprotective efficacy of a natural mixture of phytoestrogenic isoflavones (genistein, daidzein, biochanin A and formononetin) from Trifolium pratense L. (Red clover) against oxidative stress-induced cell death in human cortical cell line HCN 1-A maintained in culture. Neuronal viability was determined by MTT or trypan blue test and neuronal integrity by morphological analysis.The results obtained indicate that exposure of HCN 1-A cell cultures to hydrogen peroxide resulted in a concentration-dependent decrease in neuron viability. Concentration of H(2)O(2) ranging from 50 to 200 microg/ml were toxic to these cultures. A 24-hour pretreatment with 0.5, 1 and 2 microg/ml isoflavones extract significantly increased cell survival as evidenced by MTT or trypan blue test and significantly prevented the morphological disruption caused by H(2)O(2) as shown by microscopical inspection, indicating that neurons treated with isoflavones were protected from the cell death induced by H(2)O(2) exposure. These findings imply that the neuroprotective effect of isoflavones extract is partly associated with its antioxidant activity. Further, results of these investigations indicate that although isoflavones extract exert a neuroprotective effect, it do not promoted cortical neuron process outgrowth.     

红车轴草的化学成分研究

目的对红车轴草全草化学成分进行分离鉴定。方法采用反复硅胶柱色谱、Sephadex LH-20柱色谱、重结晶，制备薄层等方法进行分离纯化，通过理化常数测定和光谱分析鉴定其化学结构。结果分离得到9个化合物，分别鉴定为香草醛（vanillin，Ⅰ），山柰酚（kaempferol，Ⅱ），鹰嘴豆芽素A（biochaninA，Ⅲ），德鸢尾素（irilone，Ⅳ），芒柄花素（formononetin，Ⅴ），鹰嘴豆芽素A-7-O-β-D-吡喃葡萄糖苷（biochanin.A-7-O-β-D-glucopyranoside，Ⅵ），大豆素（daidzein，Ⅶ），（-）maackiain（Ⅷ），β-谷甾醇（β-sitosterol，Ⅸ）。结论化合物Ⅰ、Ⅱ为首次从该属植物中分离得到。     

测定红车轴草中刺芒柄花素含量的新方法

目的:建立了一种用同步荧光测定红车轴草中刺芒柄花素含量的新方法。方法:研究了检测条件对刺芒柄花素荧光强度的影响,以及实验的准确性、重现性和回收率。结果:该方法的线性回归方程为y=1440x-0.263,r=0.999,检出限为1.50×10-9mol/L。本方法测得红车轴草中刺芒柄花素的含量与HPLC法的结果相对偏差为1.65%。结论:说明本方法结果准确,可以满足科研和生产的要求。     

红三叶草异黄酮及其代谢研究进展

红三叶草异黄酮具有多种生理活性,从其结构特点上阐述了红三叶草异黄酮的植物雌激素功能。近年来国内外学者对其生理功能的研究发现,红三叶草异黄酮的植物雌激素作用与其代谢产物密切相关。红三叶草异黄酮属于4’-甲氧基类异黄酮,需要在生物体内通过微生物酶系作用下转化成具有双羟基结构以及活性更高的4’-羟基类异黄酮,从而能够更好地与雌激素受体结合,发挥植物雌激素作用。     

Trifolium L. – A review on its phytochemical and pharmacological profile

Plants from the genus Trifolium have been used in traditional medicine by many cultures. In Turkish folk medicine, for example, some Trifolium species are used for their expectorant, analgesic, antiseptic properties and also to treat rheumatic aches. Some species are also grown as pasture crops for animals in the Mediterranean. The high quercetin concentration and soyasaponin occurrence make the seeds of some Trifolium species a potential source of health beneficial phytochemicals for use in human nutrition. However, Trifolium pratense has also gained popularity due to research into its use for the treatment for menopausal symptoms. This paper provides an overview of the phytochemical and pharmacological profile of Trifolium species. Copyright © 2008 John Wiley & Sons, Ltd.     

Red clover Trifolium pratense (Linn.) isoflavones extract on the pain threshold of normal and ovariectomized rats – a long‐term study

Depletion of estrogens occurs in women during menopause, while in experimental animals, oophorectomy is a common method to deplete the animals of their gonadal hormones. Recently, phytoestrogens derived from plants have been tried as estrogen substitutes during menopause. In the present study an isoflavones methanol extract from red clover Trifolium pratense (Linn.) was administered orally (500 mg/kg of body weight) to ovariectomized (OVX) and normal (controls) rats for 90 and 180 days. Their pain threshold was monitored using tail flicking and formalin test methods. Observations showed that the OVX rat pain threshold was reduced due to estrogen deprivation, whereas the pain threshold levels in OVX rats treated with isoflavones extract was similar to the control animals. The present study demonstrated the influence of phytoestrogen on long‐term OVX rats in pain perception in the absence of ovarian estrogen and without toxic side effects. However, the actions of gonadal hormones on nociceptive axis are myriad and complex, so further studies on the exact physiological mechanism of the phytoestrogen action on nociceptive axis is warranted. Copyright © 2010 John Wiley & Sons, Ltd.     

Effects of phytoestrogenic isoflavones from red clover (Trifolium pratense L.) on experimental osteoporosis

The most common type of osteoporosis is bone loss associated with ovarian hormone deficiency at menopause. There is evidence that diets which contain high levels of phytoestrogenic isoflavones are associated with a low incidence of osteoporosis and menopausal symptoms. Plant extracts, which contain high levels of isoflavones, such as Red clover (Trifolium pratense L.), have been used to reduce menopausal symptoms.The objective of this study was to evaluate the preventive effects of Red clover total isoflavones on the progression of bone loss induced by estrogens deficiency (ovariectomy) in rats. Bilateral ovariectomy was performed on female Wistar rats. One week after the operation the rats were treated with an oral dose of 20 and 40 mg of total isoflavones daily for 14 weeks. The results from this study showed that the ovariectomy reduced bone mineral content, femoral weight, femoral density, mechanical strength of the tibia and increased the levels of bone specific alkaline phosphatase in the serum and the number of osteoclasts in the femur sections compared with sham operated controls. Treatment with isoflavones significantly increased bone mineral content, mechanical strength of the tibia, femoral weight, femoral density and prevented the rise of serum alkaline phosphatase levels. In addition, the treatment with isoflavones significantly reduced the number of osteoclasts compared with the ovariectomized control rats. These findings suggest that Red clover isoflavones are effective in reducing bone loss induced by ovariectomy, probably by reducing of the bone turnover via inhibition of bone resorption.     

红车轴草提取物中多环芳烃脱除工艺的研究

目的 优选红车轴草提取物中多环芳烃(PAHs)脱除工艺。方法 以PAHs脱除率为指标，考察提取物粒度、脱除溶剂、脱除方法对PAHs脱除工艺的影响。结果 最佳工艺为：红车轴草提取物超微粉碎至300目以上，用六号溶剂超声提取，对PAHs的脱除率达到98.0%以上，PAHs的残留量为10.0 ng/g以下。结论 超微粉碎-六号溶剂-超声提取法脱除红车轴草提取物中PAHs脱除率高，工艺稳定、可行。