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1.
Fusarium wilt of potato is one of the most common diseases of potato in China, and is becoming a serious threat in potato production. It has been reported that osthole from Cnidium monnieri (L.) Cusson can inhibit plant pathogens. Here, we test the anti-fungal activity of C. monnieri osthole against Fusarium oxysporum in potatoes. The results showed that at a concentration of 5 mg/mL, osthole was able to obviously inhibit mycelial growth of F. oxysporum. We found that osthole caused changes of mycelial morphology, notably hyphal swelling and darkening. Osthole significantly reduced the spore germination of Fusarium by 57.40%. In addition, osthole also inhibited the growth of other pathogens such as Fusarium moniliforme J. Sheld, Thanatephorus cucumeris Donk, and Alternaria alternata (Fr.) Keissl, but not Alternaria solani Jonesetgrout and Valsa mali Miyabe and G. Yamada. Our results suggest that osthole has considerable potential as an agent for the prevention and treatment of potato Fusarium wilt.  相似文献   
2.
蛇床子香豆素的薄层分离-直接进样-质谱鉴定   总被引:8,自引:0,他引:8  
用丙酮提取,石油醚冷冻结晶,从蛇床子中得到混合香豆素。经薄层分离 ,直接进样和质谱分析 ,鉴定出8种香豆素化合物:Ⅰ.蛇床子素(osthol) ,Ⅱ.佛手内酯(bergapten) ,Ⅲ.欧芹属素乙(imperatorin) ,Ⅳ.花椒毒素(xanthotoxin) ,Ⅴ.异回芹内酯(isopimpinellin) ,Ⅵ.别异英波托林(alloisoimperatorin) ,Ⅶ.6 -甲氧基 -8 -甲基香豆精(6_methoxy_8_methylcoumarin) ,Ⅷ.花椒毒酚(xanthotoxol)。其中Ⅵ、Ⅶ首次于蛇床子中发现。  相似文献   
3.
The extract from Cnidium officinale rhizomes was shown in a prior experiment to markedly recover otic hair cells in zebrafish damaged by neomycin. The current study was brought about to identify the principal metabolite. Column chromatography using octadecyl SiO2 and SiO2 was performed to isolate the major metabolites from the active fraction. The chemical structures were resolved on the basis of spectroscopic data, including NMR, IR, MS, and circular dichroism (CD) data. The isolated phthalide glycosides were assessed for their recovery effect on damaged otic hair cells in neomycin-treated zebrafish. Three new phthalide glycosides were isolated, and their chemical structures, including stereochemical characteristics, were determined. Two glycosides (0.1 μM) showed a recovery effect (p < 0.01) on otic hair cells in zebrafish affected by neomycin ototoxicity. Repeated column chromatography led to the isolation of three new phthalide glycosides, named ligusticosides C (1), D (2), and E (3). Ligusticoside C and ligusticoside E recovered damaged otic hair cells in zebrafish.  相似文献   
4.
蛇床子对土壤中七种金属元素选择性富集作用研究   总被引:3,自引:0,他引:3  
采用火焰原子吸收分光光度法对十个产地的蛇床子及其植物根部土壤中的七种金属元素的含量进行了测定,通过比较对该植物对这七种金属元素的选择性富集作用进行了讨论。  相似文献   
5.
Yan F  Liang Z  Jianna C  Zhengtao W  Losahan X  Zhengxing Z 《Talanta》2001,53(6):1155-1162
Application of multivariate data analysis has become a popular method in the last decades, mainly because it can provide information not otherwise accessible. The information includes classification, searching similarities, finding relationships, finding physical significance to principal components, etc. Fifty three Chinese medicinal herbs of eleven kinds of coumarins were collected and determined by HPLC. The results were studied by principal component analysis (PCA) and cluster analysis. It was showed that the samples could be clustered reasonably into different groups, which correspond with variation of regularity and distribution of coumarin of Cnidium monnieri fruits in different regions of China.  相似文献   
6.
A rapid CEC method with poly(butyl methacrylate‐co‐ethylene dimethacrylate‐co‐[2‐(methacryloyloxy)ethyl] trimethylammonium chloride) monolithic column has been developed for separation and determination of four coumarins (isopimpinelline, bergapten, imperatorin, and osthole) in Fructus cnidii extracts. The effect of polymerization condition including the monomers ratio and the porogens ratio were studied. The mobile‐phase composition, such as the composition of organic solvent, the concentration and pH of buffer, was also optimized. Under the same condition (50% ACN and 50% of a 10 mM sodium dihydrogen phosphate electrolyte at pH 4.95), in contrast to 25 min of analysis time in HPLC and 10 min of analysis time in pCEC, a fast separation of these analytes was achieved in less than 5 min in CEC. Method validation was developed in accordance with the analytical procedures. Intra‐ and interday precisions (RSD) for relative retention time and peak area were less than 1.69 and 4.63%, and LODs were lower than 0.5 μg/mL. Calibration curves of four compounds also showed good linearity (r2>0.995). The mean recoveries ranged between 93.91 and 98.65%. With this CEC system, the quality of F. cnidii extracts from various resources was evaluated by determining the contents of the four coumarins.  相似文献   
7.
真空溶剂蒸发全二维液相色谱接口及其应用   总被引:2,自引:1,他引:1  
田宏哲  徐静  关亚风 《分析化学》2008,36(6):860-864
以正相色谱(NPLC)为第一维,反相色谱(RPLC)为第二维,建立了真空溶剂蒸发接口的全二维液相色谱系统(VEI-C2DLC)。样品首先在第一维(CN色谱柱)进行正相分离,第一维洗脱产物被交替存储到十通阀上的两个定量环中,与此同时对切割到定量环内的第一维组分进行在线真空蒸发,被分析样品组分保留在定量环内壁内,而溶剂被蒸发除去。十通阀切换后保留在该定量环内的样品组分被洗脱到第二维进行反相分离,如此反复循环使第一维组分完全转移到第二维。采用标准样品和天然植物蛇床子提取液对该全二维液相系统进行了评价。  相似文献   
8.
短波近红外光谱法对蛇床子SFE萃取产物的定量分析   总被引:1,自引:0,他引:1  
郭晔  曲楠  王彬  任玉林 《分析试验室》2007,26(11):49-52
利用中药蛇床子CO2超临界萃取(SFE)的萃取物的短波近红外漫反射光谱(800~1100 nm),以HPLC分析值作参比值,采用化学计量学中的偏最小二乘法(PLS)建立短波近红外漫反射光谱与蛇床子SFE萃取物中主要成分蛇床子素和欧前胡素间定量分析数学模型.实现了快速、无损的测定双组分中药的有效成分.讨论了光谱的预处理方法和主成分数对PLS定量预测蛇床子萃取物中蛇床子素和欧前胡素含量能力的影响,并对预测集样品进行预测.  相似文献   
9.
Cnidium monnieri (L.) Cusson is a well-known Chinese medicinal plant, which has been used for the treatment of impotence, frigidity, and skin-related diseases, and exhibits strong antipruritic, antiallergic, antidermatophytic, antibacterial, antifungal, and antiosteoporotic activities. A high-speed counter-current chromatography method was developed for the separation and purification of five bioactive coumarins from this plant. The crude coumarins were obtained by ethanol extraction from the dried fruits of Cnidium monnieri (L.) Cusson under sonication. High-speed counter-current chromatography with the two-phase solvent systems n-hexane-ethyl acetate-ethanol-water (5:5:4:6, v/v) and n-hexane-ethyl acetate-ethanol-water (5:5:6:4, v/v) was successfully performed with stepwise elution. The five relatively pure coumarins were obtained from 500 mg of the crude extract in a single run. Their purities were 90.6-98.9%, and the recoveries were 85.7-94.2%.  相似文献   
10.
采用火焰原子吸收分光光度法分别对蛇床子全药材、水提醇沉以及总香豆素提取过程不同部位的六种金属元素的含量进行了测定。实验结果为微量元素的形态分析及其对药理作用的贡献提供参考数据。  相似文献   
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