肉苁蓉研究进展

本文就肉苁蓉资源分布、化学成分、分离提纯、药理作用和资源开发利用作一综述,并展望其发展前景     

Purification and Properties of UDP-galactose 4-Epimerase from Bifidobacterium bifidum

UDP-galactose 4-epimerase (EC 5.1.3.2) was purified to a homogeneous state from Bifidobacterium bifidutn grown on a glucose medium. The molecular weight was estimated to be about 90,000. The purified enzyme was very stable and 60 % of its initial activity survived three months of storage at 4°C even at a low protein concentration (0.2 mg/ml). The optimum pH was 9.0, and the Km values for UDP-galactose and UDP-glucose were 5.4 × 10^-4 M and 1.4×10 ^-3 M. UDP was a competitive inhibitor. The enzyme activity was stimulated by various sugar phosphates, but was slightly inhibited by fructose 1,6-diphosphate (FDP). A high concentration of galactose or glucose, which had no effect by itself, inhibited the activity in combination with UMP. The inhibition by FDP was also enhanced by combination with UMP.     

Improvement of phenylethanoid glycosides production by a fungal elicitor in cell suspension culture of Cistanche deserticola

When, on the 15th day of growth, an elicitor from Fusarium solani was added at 40 mg l^–1 to Cistanche deserticola cell suspension cultures, the contents of echinacoside, acteoside and total phenylethanoid glycosides (PeGs) in cultured cells all increased over the next 27 d by over 100% to 15 mg g^–1 dry wt, 9 mg g^–1 dry wt and 57 mg g^–1 dry wt, respectively. The final biomass (1.3 mg dry wt ml^–1) was not affected.     

肉苁蓉多糖的促淋巴细胞增殖作用

目的研究肉苁蓉多糖（CDPS）对小鼠淋巴细胞增殖的影响。方法MTT法检测小鼠脾淋巴细胞的增殖。环磷酰胺（Cy）复制免疫功能低下的动物模型,分别测定正常及免疫低下动物脾脏、胸腺指数。胸腺细胞增殖法测定白细胞介素-2（IL-2）活性。结果CDPS对丝裂原（ConA及LPS）活化淋巴细胞及未活化正常细胞均有明显促增殖作用,并促进淋巴细胞IL-2的分泌。腹腔给药显示CDPS具明显提高正常及免疫低下小鼠的脾指数,对因Cy所致胸腺指数的降低也有显著的对抗作用。结论CDPS可显著促进小鼠脾淋巴细胞增殖,该作用可能与其促IL-2分泌有关。     

Structural characterization and immunological activity of two cold-water extractable polysaccharides from Cistanche deserticola Y. C. Ma

Two major polysaccharide fractions, CDA-1A and CDA-3B, were isolated from the cold-water extract of Cistanche deserticola Y. C. Ma, a holoparasitic plant and a valuable traditional Chinese medicine, using anion-exchange chromatography on DEAE-cellulose and gel-permeation chromatography on Sephacryl S-300 and Sephadex G-150. Their major structural features were elucidated using component and linkage analyses, periodate oxidation, Smith degradation, partial acid hydrolysis, and NMR spectroscopy. The results indicated that CDA-1A is an alpha-(1-->4)-D-glucan with alpha-(1-->6)-linked branches attached to the O-6 of branch points and that CDA-3B is an RG-I polysaccharide containing a typical rhamnogalacturonan backbone and arabinogalactan or arabinan branches. Bioactivity tests showed that CDA-1A is inert for T-cell proliferation stimulation but active for B-cell proliferation, while CDA-3B is potent for the stimulation of both T- and B-cell proliferation.     

一种新的肉苁蓉甙类化合物的分离方法

简单介绍了一种从肉苁蓉中提取得到肉苁蓉甙类化合物的方法,避免了乙酸乙酯和正丁醇的萃取,便于工业化应用,同时还可获得纯度较高有甜菜碱。     

基于叶绿体rps16基因和核基因ITS片段研究肉苁蓉属系统位置

在前人对列当科系统发育研究的基础上,追加了肉苁蓉属(Cistanche)的基因序列数据,运用最大简约法、最大似然法和贝叶斯推断方法探讨了其在列当科中的系统位置及列当科中属间关系.基于rps16基因序列及rps16+ ITS联合序列建立了列当科系统发育树,结果显示,肉苁蓉属、列当属(Orobanche)以及草苁蓉属(Boschniakia)聚在同一进化枝内,肉苁蓉属和列当属表现出最近亲缘关系;列当科中的全寄生类群、半寄生类群和非寄生类群分属在3个不同分支中.     

外源信号物质对肉苁蓉种子萌发与吸器形成内源激素水平变化的影响

利用外源信号物质氟草敏（norflurazon）和2,6-二甲氧基对苯醌（2,6-DMBQ）分别诱导肉苁蓉种子萌发与吸器形成,研究它们在此过程中对内源激素脱落酸（ABA）、赤霉素（GA3）、吲哚乙酸（IAA）、玉米素核苷（ZR）水平变化的影响。结果表明：在诱导肉苁蓉种子萌发时,经norflurazon处理0～168h后,种子中ABA水平呈现显著降低的变化趋势,GA3、IAA、ZR水平呈现显著升高的变化趋势。在诱导肉苁蓉种子萌发体吸器形成时,经2,6-DMBQ处理0～72h后,肉苁蓉种子萌发体ABA水平变化不显著,GA3、IAA、ZR水平均呈现显著升高的变化趋势。表明在肉苁蓉种子萌发与吸器形成中外源信号物质nor-flurazon和2,6-DMBQ能影响内源激素水平的变化。