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1.
笔者经过长时间对豆科的海红豆属Adenanthera、红豆属Ormosia、野扁豆属Dunbaria、山黑豆属Dumasia、胡枝子属Lespedeza…等12个属作了专属系统分类研究,陆续发现了一些新分类群。于是进行再调研与复查核实,补点采集和确认论证,在本文先报导1个新属、4个新种、3个亚种新组合和2个新变种,它们都是中国地理分布的地区特有分类群(除去1个亚种)其余将在另文续报。除此。作了其化学成分、药理试验、花粉与种皮的扫描电镜SEM观测及拍片分析和花、果、叶片和幼枝的比较形态解剖等研究,为新分类群的分类和区别及其亲缘关系提供佐证,为其新药筛选和其他应用开发、保护提供依据或参考。  相似文献   
2.
目的 研究雪山芪He dysaram sikkimense Benth.ex Baker.var.rigidum Hand、-Mass.的化学成分。方法 采用反复硅胶柱层析分离纯化,通过理化常数测定和光谱分析鉴定化合物的结构。结果 从雪山芪干燥根中分离得到9个化合物。根据波谱分析和理化数据,鉴定出其中8个化合物分别为:羽扇豆醇(lupeol,1)、4′-羟基-7-甲氧基异黄酮(isoformononetein,Ⅱ)、4′-羟基-6,7-二甲氧基异黄酮(3-[4-hydroxyphenyl-6,7-dimetoxy-4H-1-benzopyran-4-one],Ⅲ)、熊果酸(ursolic acid,Ⅳ)、山嵛酸-α-单甘油酯(docosanooic acid-2,3-d.hydroxypropyl ester,Ⅴ)、二十四烷酸(lignoceric acid,Ⅵ)、β-谷甾醇(β-sitosterol,Ⅶ)及蔗糖。结论 以上化合物均为首次从该植物中分得。  相似文献   
3.
From the roasted seeds ofCassia tora L., a new naphthopyrone glycoside was isolated and characterized as 10-[(β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl)oxyl-5-hydroxy-8-methoxy-2-methyl-4H-naphtho [1,2-b]pyran-4-one(isorubrofusarin gentiobioside). Along with isorubrofusarin gentiobioside, alaternin and adenosine were isolated and identified.  相似文献   
4.

Ethnopharmacological relevance

Acacia mellifera (Vahl) Benth (Leguminosae) is a subtropical medicinal plant that is widely used in traditional African medicines against various diseases such as pneumonia and malaria.

Aim of the study

The present study was performed to evaluate the antimicrobial effects of extracts from the stem bark of Acacia mellifera.

Materials and methods

The extracts were examined for antibacterial and antifungal activity using the disc-diffusion method against bacterial strains: Streptococcus pneumoniae (ATCC 25923), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 35218), Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) and fungal strains Candida albicans (ATCC 90028), Candida krusei (ATCC 6255), Cryptococcus neoformans (ATCC 6603) and clinical isolates of Microsporum gypseum and Trichophyton mentagrophytes.

Results

Some of these extracts were found to be active against some bacterial and fungal strains and were further fractionated to give 12 pure compounds. The methanolic and methanol:dichloromethane (1:1) extracts exhibited antibacterial and antifungal activity. The two were active against Staphylococcus aureus (ATCC 25923), Microsporum gypseum, and Trichophyton mentagrophytes. Activity guided fractionation led to isolation of two active compounds: 3-(Z)-cis coumaroylbetulin and 30-hydroxylup-20 (29)-en-3β-ol which were against Staphylococcus aureus (ATCC 25923), Microsporum gypseum, Trichophyton mentagrophytes and Pseudomonas aeruginosa (ATCC 27853).

Conclusions

These results may partly explain and support the use of Acacia mellifera stem barks for the treatment of infectious diseases in traditional Kenya medicine.  相似文献   
5.
6.
毛鸡骨草地上部分的化学成分   总被引:5,自引:0,他引:5  
目的:对毛鸡骨草Abrus mollis Hance的化学成分进行研究。方法:运用多种柱层析方法进行分离纯化,通过波谱法鉴定分离得到的单体化合物的结构。结果:从毛鸡骨草地上部分的正丁醇部位分离并鉴定了8个化合物,黄酮类化合物:芹菜素-6-C-葡萄糖-8-C-葡萄糖苷(1),芹菜素-6-C-阿拉伯糖-8-C-葡萄糖苷(2),芹菜素-6-C-葡萄糖-8-C-阿拉伯糖苷(3),芹菜素-6-C-葡萄糖-8-C-木糖苷(4),木犀草素-6-C-葡萄糖苷(5),木犀草素(6);色原酮类化合物:异双花母草素(7);木脂素类化合物:(+)-异落叶松树脂醇(8)。结论:化合物1~8均为首次从该属植物中分离得到。  相似文献   
7.
鸡骨草的化学成分研究   总被引:10,自引:0,他引:10  
史海明  温晶  屠鹏飞 《中草药》2006,37(11):1610-1613
目的研究鸡骨草Abrus cantoniensis全株的化学成分。方法柱色谱及高效液相色谱法分离其成分,光谱法鉴定其结构。结果分离鉴定了18个化合物,分别为β-谷甾醇(Ⅰ)、羽扇豆醇(Ⅱ)、原儿茶酸乙酯(Ⅲ)、胡萝卜苷(Ⅳ)、原儿茶酸(Ⅴ)、肌醇甲醚(Ⅵ)、7,3′,4′-三羟基-黄酮(Ⅶ)、腺嘌呤(Ⅷ)、腺嘌呤核苷(Ⅸ)、biflorin(Ⅹ)、isobi-florin(Ⅺ)、相思子碱(ⅩⅡ)、N,N,N-三甲基-色氨酸(ⅩⅢ)、大豆皂苷(ⅩⅣ))、槐花皂苷(ⅩⅤ)、去氢大豆皂苷(ⅩⅥ)、abrisaponin So1(ⅩⅦ)、白桦酸(ⅩⅧ)。结论Ⅲ、Ⅴ、Ⅶ~Ⅺ和皆为首次从本属中得到。除Ⅰ、ⅩⅡ、ⅩⅣ~ⅩⅥ外,其余13个化合物皆为首次从该植物中得到。  相似文献   
8.
Two new flavonoids, named sphaerophyside SA and sphaerophyside SB, together with 15 known flavonoids were isolated from the ethanolic extract of the seeds of Sphaerophysa salsula (Pall.) DC. The structures of the new compounds were elucidated mainly on the basis of the 1D and 2D NMR data.  相似文献   
9.
A new compound, sphaerophysin A (1), together with 16 known compounds (2-17) were obtained from the ethanolic extract of the seeds of Sphaerophysa salsula. The structure of 1 was elucidated on the basis of spectral and chemical evidence. Compounds 2-17 were isolated from the plant for the first time.  相似文献   
10.
The antioxidant activity of the stem bark from Albizzia julibrissin was evaluated for its potential to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, to inhibit the generation of the hydroxyl radical (*OH), total reactive oxygen species (ROS) and to scavenge authentic peroxynitrites (ONOO-). The methanol extract of A. julibrissin exhibited strong antioxidant activity in the tested model systems. Therefore, it was further fractionated using several solvents. The antioxidant activity of the individual fractions were in the order of ethyl acetate (EtOAc) > n-butanol (n-BuOH) > dichloromethane (CH2Cl2) > and water (H2O). The ethyl acetate soluble fraction, which exhibited strong antioxidant activity, was further purified by repeated silicagel, Sephadex LH-20 and RP-18 gel column chromatography. Sulfuretin (1) and 3',4',7-trihydroxyflavone (2) were isolated as the active principles. Compounds 1 and 2 exhibited good activity in all tested model systems. Compound 1 exhibited five times more inhibitory activity on the total ROS than Trolox. Compound 2 showed six times stronger DPPH radical scavenging activity than L-ascorbic acid. These results show the possible antioxidant activity of the A. julibrissin crude extract and its major constituents.  相似文献   
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