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101.
Chemical investigation of methanol extract of the fruits of Diploclisia glaucescens (Menispermaceae) furnished two new bidesmosidic saponins 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl]phytolaccagenic acid 28-O-beta-D-glucopyranosyl ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]phytolaccagenic acid 28-O-beta-D-glucopyranosyl ester, together with known 3-O-beta-D-glucopyranosylphytolaccagenic acid 28-O-beta-D-glucopyranosyl ester and 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]serjanic acid 28-O-beta-D-glucopyranosyl ester. The last saponin is reported for the first time from the family Menispermaceae.  相似文献   
102.
据笔者对采自云南勐腊的“矩叶蓝果树”模式标本及曾被定为该变种的标本研究,该变种具聚伞花序,花梗长3-5mm,雌花子房上位,核果果皮极薄,内具1种子,并非蓝果树属植物,与茶茱萸科粗丝术属之粗丝本完全同种。粗丝木产中国西南至东南部,印度、斯里兰卡、缅甸、泰国、印度支那也有分布。  相似文献   
103.
油茶皂素化学和物理特性及其开发利用研究   总被引:1,自引:0,他引:1  
油茶皂素学名茶皂角甙,结构糖是由葡萄糖醛酸,阿拉伯糖,木糖及半乳糖组成,结构酸是由反(顺)白芷酸及醋酸组成。茶皂角甙是由结构相似5─7种三萜类皂甙元构成。油茶皂素的表面活性主要是结构一端为疏水的脂肪酸基团,另一端为结构糖,结构酸亲水基团,吸附和胶团化,使皂素可用来做乳化剂,洗涤剂,发泡剂,分散剂,润湿剂,洗发剂,清洗剂,柔软剂等。  相似文献   
104.
油茶饼粕中茶皂素的提取及脱色研究   总被引:6,自引:0,他引:6  
以油茶饼粕为原料,通过有机溶剂进行浸取,研究并确定提取了茶皂素的最佳工艺为乙醇体积分数75%,料液比(g:m l)为1:4,提取时间2 h,提取温度60℃;脱色的最佳条件为pH9,脱色温度60℃,脱色时间1 h,加入H2O220 mL。在此条件下提取的茶皂素得率为16.6%,纯化的茶皂素质量分数达到87.3%。  相似文献   
105.
羊耳朵叶化学成分的研究   总被引:3,自引:0,他引:3  
从羊耳朵叶(密蒙花 Buddle ja officinalis Maxim的叶)中分得8个化合物,分别鉴定为3个萜:羽扇豆醇乙酸酯(lupeol acetute)(1),cycloeucalenol(2),chondrillasterol(3)和5个苯丙素酚甙:verbascoside((4),poliumoside(5),β-hydroxyacteoside(6),echinacoside(7)和cistanoside F(8)。化合物1,2,3为首次从该属植物中获得。  相似文献   
106.
Biodegradation and hydrophobicity of Pseudomonas spp. and Bacillus spp. strains were tested at different concentrations of the biosurfactant Quillaya saponin. A model mixture of hydrocarbon (dodecane and hexadecane) was used for estimating the influence of surfactants on biodegradation. The bacterial adhesion to hydrocarbon method for determination of bacterial cell surface hydrophobicity was exploited. Among the tested bacterial strains the higher hydrophobicity was noticed for Pseudomonas aeruginosa TK. The hydrophobicity of this strain was 84%. The highest hydrocarbon biodegradation was observed for P. aeruginosa TK (49%) and Bacillus subtilis (35%) strains after 7 days of experiments. Generally the addition of Quillaya saponin increased hydrocarbon biodegradation remarkably. The optimal concentration proved to be 80 mg l−1. The degree of hydrocarbon biodegradation was 75% for P. aeruginosa TK after the addition of saponin. However the most significant increase in biodegradation after addition of Quillaya saponin was in the case of P. aeruginosa 25 and Pseudomonas putida (the increase of biodegradation from 21 to 52% and from 31 to 66%, respectively). It is worth mentioning that decrease of hydrophobicity is correlated with the best biodegradation by P. aeruginosa strain. For the remaining strains, no significant hydrophobicity changes in relation to the system without surfactant were noticed.  相似文献   
107.
A γ-pyronyl triterpenoid saponin termed chromosaponin 1 (CSI), a conjugate of soyasaponin I and γ-pyrone, was found at 3 mM to stimulate the growth of lettuce root ( Lactuca sativa L. ev. Grand Rapids) to about 190% of the control. Since CSI is an amphipathic reductant, the stimulating effect of this saponin was compared with other reductants and other surface-active compounds. Trolox (2-carboxy-2.5.7.8-tetraamethyl-6-chromanol). another amphipathic reductant, also stimulated root growth, while other hydrophilic reductants including ascorbate. NADPH, NADH and glutathione did not. Some surfactants promoted root growth but their stimulating effects were smaller than the optimum effect of CSI. These results suggest a possible Function of CSI as an amphipathic reductant in root growth regulation.  相似文献   
108.
商陆毛状根的诱导、培养及其扼甙的产生   总被引:9,自引:0,他引:9  
发根农杆菌(Agrobacterium rhizogenes)R1601感染商陆叶片外植体1周后,在其切口处产生毛状根,20d后产生毛状根的外植体比例达70%,毛状根可直接从叶片外植体叶脉处或从叶脉处产生的愈伤组织上产生,毛状根能在无激素的MS培养基上自主生长,其呼吸速率比对照根提高85.6%,冠瘿碱检测和PCR扩增结果表明,发根农杆菌RiT-DNA的冠瘿碱合成酶基因及其Ri质粒的rol基因均已在商陆毛状根基因组中得到表达。毛状根中总皂甙含量约为自然根的1.54倍,但其多糖含量则仅为非转化根的70%。  相似文献   
109.
In traditional Chinese medicine, Gynostemma pentaphyllum (Thunb.) Makino is a herbal drug of extreme versatility and has been extensively researched in China. The dammarane saponins isolated from Gynostemma pentaphyllum, namely gypenosides or gynosaponins, are believed to be the active components responsible for its various biological activities and reported clinical effects. This review attempts to encompass the available literature on Gynostemma pentaphyllum, from its cultivation to the isolation of its chemical entities and a summary of its diverse pharmacological properties attributed to its gypenoside content. Other aspects such as toxicology and pharmacokinetics are also discussed. In vitro and in vivo evidence suggests that Gynostemma pentaphyllum may complement the popular herbal medicine, Panax ginseng, as it also contains a high ginsenoside content and exhibits similar biological activities.  相似文献   
110.
利用溶剂萃取,大孔树脂、硅胶和聚酰胺的色谱法,对缘毛紫菀的正丁醇萃取物的化学成分进行了研究,从中分离得到4个三萜皂苷,经1H-NMR、13C-NMR等现代波谱技术及化学方法分别鉴定为续断皂苷B(1)、臭瓜皂苷A(2)、三褶脉紫菀皂苷A(3)和东风菜皂苷A4(4)。化合物1为首次从该属植物中得到,化合物2、3和4为首次从缘毛紫菀中得到。  相似文献   
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