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41.
Hong Wei LIU Xin Sheng YAO Nai Li WANG Guo Ping CAI 《中国化学快报》2006,17(2):211-214
The Aesculus genus consists of about thirty species distributed in Asia, Europe andAmerica. There are sixteen species distributed in China, and most of them are used asherbal medicines for the treatment of distention and pain in the chest and abdomen. Anu… 相似文献
42.
以滇重楼的根茎为实验材料,重楼甾体总皂甙的提取率为评价指标,运用L16(4^5)正交试验,考察了皂甙浸出过程中的浸泡时间、乙醇浓度、超声剂量、粗粉质量与浸泡用乙醇体积之比4个因素在4个水平下的工艺过程,筛选出了最佳提取工艺。实验结果表明:粗粉(0.45mm粒径)用30%的乙醇溶液浸泡36h后,超声30min,粗粉质量与(浸泡)乙醇的体积比1:15为最佳提取条仲,重楼甾体总皂甙的提取率为9.50%。以近红外漫反射光谱技术为在线监控手段,利用模式识别方法对AB-8树脂分离精制过程中的吸附、杂质洗脱和甾体总皂甙解吸洗脱等工艺过程进行了在线质量监控方法研究,建立了优化的质量可控的分离纯化方法。 相似文献
43.
A new compound 1 was isolated from the methanolic extract of the stems of the Caesalpinia pulcherrima Linn. along with a reported compound (2) 3-O-β-D-glucopyranosyl-(1→4)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester. The new compound 1 has m.p. 272–274°C, m.f. C46H74O17, [M]+ m/z 898. It was characterised as 3-O-β-D-glucopyranosyl-(1→4)-α-L-arabinopyranosyl hederagenin 28-O-β-D- xylopyranosyl ester by various colour reactions, chemical degradations and spectral analyses. Antibacterial activity of compound 1 was screened against various Gram-positive and Gram-negative bacteria and showed significant results. 相似文献
44.
Qing Tao Yu Ping Li Zhi Ming Bi Jun Luo Xiao Dan Gao 《中国化学快报》2007,18(5):554-556
Two new saponins named mongholicoside A (1) and mongholicoside B (2) were isolated from the aerial part of Astragalus membranaceus var. mongholicus. Their structures were determined by 1D and 2D NMR, ESI-MS techniques and chemical methods. 相似文献
45.
Jeong Gwi-Taek Park Don-Hee Ryu Hwa-Won Lee Woo-Tai Park Kyungmoon Kang Choon-Hyoung Hwang Baik Woo Je-Chang 《Applied biochemistry and biotechnology》2002,98(1-9):1129-1139
Panax ginseng hairy roots were transformed by Agrobacterium rhizogenes KTCT 2744. They showed an active branching pattern and fast growth in hormone-free medium, and good growth at 23°C, pH 5.8,
1/2 MS medium, and 3% sucrose. Sucrose provided the highest growth among seven carbon sources tested. Six complex media were
also tested. In the combined sugar study, hairy roots grew better on sucrose without glucose or fructose than with glucose
or fructose. In the 1/2 MS basal medium, 30 mM in nitrogen and 0.62 mM phosphate salt concentration was the optimum. The growth ratio was maximal at an inoculum size of 0.4% (w/v). Crude saponin
and polysaccharide levels were also measured. 相似文献
46.
A New Cyclic Bisdesmoside from Tubers of Bolbostemma paniculatum 总被引:2,自引:0,他引:2
HaiFengTANG YangHuaYI ShuYuZHANG PengSUN LingLI DaZhengZHOU 《中国化学快报》2005,16(4):479-482
The structure of tubeimoside V (1), a new cyclic bisdesmoside, isolated from tubers of Bolbostemma paniculatum (Tu Bei Mu), was established by means of 2D NMR spectral and chemical methods. Compound 1 has inter-saccharide chain bridging by a dicrotalic acid to form aunique macrocyclic structure. 相似文献
47.
Kun Zou Jun Wu Ming Du Chuang Liu Zi Chun Tang jun Zhi Wang 《中国化学快报》2007,18(1):65-68
A pair of diastereoisomeric furostanol saponins was obtained from the n-butanol fraction of methanol extract from Tupistra chinensis rhizomes,a folk medicine of Shennongjia Forest District of Hubei Province.Their structures were determined,on the basis of chemical and spectroscopic evidences. 相似文献
48.
In this paper, the fully anisotropicoverall tumbling motions and side groups internal rotation of ocotillol-type saponins separated from the leaves of Panax Quidquefolium L. are investigated by ~(13)C nuclear magnetic relaxation. The fully anisotropic overall tumbling motion model with methyl conformation jumps internal rotation among three equivalent sites is presented, and the spectral density function of this model is derived. The rotation rates for overall tumbling motions to ocotillol-type saponins (OTS) are computed by Woessner's fully anisotropic overall tumbling motion model, and the internal rotation rate and barrier for side groups in OTS are calculated using free diffusion internal rotation model, restriction diffusion internal rotation model and conformation jumps internal rotation model, respectively. 相似文献
49.
<正>One new dammarane-type triterpene saponin,named(20S)-3β,20,21-trihydroxydammar-24-ene 3-O-[α-L-rhamnopyranosyl- (1→2)][β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside(1),was isolated from the aerial parts of Gynostemma pentaphyllum (Thunb.) Makino.Its structural elucidation was accomplished mainly on the basis of the interrelation of spectroscopic methods, such as IR,HR-TOF-MS,NMR. 相似文献
50.
Ya Juan Xu Tun Hai Xu Jun Ying Yang Sheng Xu Xie Yue Liu Yun Shan Si Dong Ming Xu 《中国化学快报》2010,21(5):580-583
<正>Two new furostanol glycoside,26-O-β-D-glucopyranosyl-(25S)-5α-furost-3β,22α,26-triol-3-O-β-D-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-β-D-galactopyranoside(1) and 26-O-β-D-glucopyranosyl-(25S)-5α-furost-20(22)-en-2α,3β,26-triol-3-O-β-D-glucopyranosyl-(1→2)-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside(2) were isolated fromthe fruits of Tribulus terrestris L.The structures of two new furostanol saponins were elucidated by spectroscopic methods. 相似文献