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91.
A new glycosylated triterpene has been isolated from the seeds of Centratherum anthelminticum, a medicinally important plant. The structural analysis of its acetylated derivative was performed by 1H, 13C NMR, 1H-1H COSY, HMQC, HMBC and DEPT spectroscopy. The saponin was shown to contain hederagenin and six sugar residues forming two glycosyl chains. The complete structure of the saponin was established as 3-O-[beta-D-glucopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]-28-O-[beta-D-glucuronopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranosyl]-hederagenin.  相似文献   
92.
三七细胞大量(发酵)培养的研究   总被引:1,自引:0,他引:1  
三七(Panax notoginseng)细胞发酵培养的皂甙含量为干重的11.21%,皂甙产率为1513.3mg·L~(-1),细胞培养物产率为每月13.58g干重·L~(-1),均比悬浮培养高。接种量的增加能明显地提高生长速率、皂甙产率以及细胞培养物产率。通气速率0.8vvm较适合于三七细胞的发酵培养。在发酵培养过程中pH值由5.8逐渐降至3.92,没有出现回升。  相似文献   
93.
综合利用薯芋淀粉生产肌苷的研究   总被引:3,自引:0,他引:3  
本文报道综合利用野生薯芋属植物盾叶薯芋(Dioscorea zingibensisC.H.wright)和穿龙薯芋(Dioscorea nipponica Makino)中的淀粉生产肌苷(Inosine)的方法。将薯芋原料带水磨碎,在水中筛分得到皂甙淀粉浆,用稀酸水解该物质使淀粉糖化,分离后得到糖液和糖渣。糖液加氮源和无机盐,发酵生产肌苷。糖渣再水解提取薯芋皂甙元。  相似文献   
94.
人参细胞大量培养的研究   总被引:5,自引:0,他引:5  
人参细胞培养液的 pH 值在培养过程中先迅速降低然后缓缓回升,后又趋于平稳。合成皂甙高峰在细胞生长对数期稍后出现。生产皂甙的最佳收获期,细胞悬浮培养为20—25天,细胞发酵培养为15—18天。细胞生长和皂甙累积要求有一个稳定而又适宜的 pH 值环境。发酵培养无论对细胞生长、培养规模、还是皂甙含量均是一种较为理想的培养方式。  相似文献   
95.
氨法提取油茶皂素   总被引:12,自引:0,他引:12  
本文报导了一种在常温下用稀氨水从油茶饼中提取油茶皂素的方法,并讨论了影响产品颜色的诸因素。粗产品为淡黄色粉末,粗产品的得率大于9.0%,皂素含量为80%。残渣可用作饲料。  相似文献   
96.
从单条草(LysimachiacandidaLindl)全草中分离出3个皂甙类化合物,经波谱分析并结合化学方法鉴定为:报春花素A3OβD吡喃木糖基(1→2)βD吡喃葡萄糖基(1→4)[βD吡喃葡萄糖基(1→2)]αL吡喃阿拉伯糖甙(1)、原报春花素A3OβD吡喃木糖基(1→2)βD吡喃葡萄糖基(1→4)[βD吡喃葡萄糖基(1→2)]αL吡喃阿拉伯糖甙(lysikoianoside,2)和α菠甾醇葡萄糖甙(3)。其中1是新化合物,命名为单条草甙(candidoside)。  相似文献   
97.
The effect of disruption procedure on the subcellular distribution and the activities of 11 enzymes catalyzing the glycolytic pathway in Trypanosoma brucei has been studied. The activities of the enzymes varied with the lytic procedure used. Maximum specific enzyme activity values were obtained after treatment with saponin whereas digitonin treatment gave the lowest results. The intracellular location of the enzymes was examined by means of differential centrifugation following cell lysis with saponin, Triton X-100, digitonin, or by freezing and thawing. Irrespective of the method of cell lysis employed, the six enzymes, hexokinase, phosphofructokinase, aldolase, phosphoglycerate kinase, glycerol phosphate dehydrogenase, and glycerokinase, were particulate. Of the remaining 5 enzymes, digitonin liberates only phosphoglycerate mutase (partially); saponin or Triton X-100 liberates phosphoglucose isomerase, phosphoglycerate mutase, enolase, and pyruvate kinase but not glyceraldehyde 3-phosphate dehydrogenase; freezing and thawing acts like saponin or Triton X-100 except that it fails to liberate phosphoglucose isomerase, while cell grinding with silicon carbide liberates only glyceraldehyde phosphate dehydrogenase (partially), phosphoglycerate mutase, enolase, and pyruvate kinase. The relative maximal activities of the enzymes suggest that the rate-limiting steps in glycolysis in T. brucei are the reactions catalyzed by aldolase and phosphoglycerate mutase.  相似文献   
98.
Fifteen alfalfa populations were tested for resistance to the seedling damping-off disease sourced by Rhizoctonia solani, Fusarium solani, and Macrophomina phaseolina. In a laboratory experiment, saponin treatment significantly diminished the mycelial growth of the causal fungi of alfalfa damping-off disease. Roots of the fifteen alfalfa populations varied in saponin and lignin content. Selection for the considerably resistant plants leads to the best growth performance, desirable yield, and high nutritive values such as crude protein (CP), crude fier (CF), nitrogen free extract (NFE), ash, and ether extract (EE) contents. For the PCR reaction, 10 SSR pairs of the JESPR series primers and the cDNA-SCoT technique with seven primers were used. SSR and SCoT revealed some unique markers that could be linked to resistance to damping-off disease in alfalfa that appeared in the considerably resistant alfalfa population (the promised pop.). SSR and SCoT markers can be an excellent molecular method for judging genetic diversity and germplasm classification in tetraploid alfalfa. We recommend breeding for saponin concentration in the alfalfa plant may affect resistance to some diseases like root rot and damping-off because saponin might improve plant growth, yield, and nutritional values.  相似文献   
99.
Ginsenoside Compound K (CK) showed potent activity against IgE for the treatment of asthma. A series of CK analogues were then synthesized by straightforward procedures. The in vivo anti-IgE activity evaluations using the OVA-induced asthmatic mouse model revealed preliminary SARs of the CK analogues, which showed that the sugar type, modifications on A-ring and the C20 side chain of CK all affected much on the activities. Primary SARs optimization led to the discovery of compounds T1, T2, T3, T8 and T12, which displayed superior or comparable anti-asthmatic effects (IgE value?=?1237.11?±?106.28, 975.82?±?160.32, 1136.96?±?121.85, 1191.08?±?107.59 and 1258.27?±?148.70?ng/mL, respectively) in comparison with CK (1501.85?±?184.66?ng/mL). These potent compounds could serve as leads for further development.  相似文献   
100.
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