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91.
A novel enhanced triterpenes fermentation production process by Ganoderma lucidum G0119 with the addition of oleic acid in the medium has been developed and optimized. All of the six exogenous additives tested were found to exhibit stimulatory effect on mycelial growth and triterpenes biosynthesis by G. lucidum. The results show that oleic acid addition had significant role in promoting triterpenes production. The optimal concentration and time of oleic acid addition were determined to be 30 mL/L and 0 h, respectively. Furthermore, three significant factors influencing triterpenes production were identified as glucose, magnesium sulfate and temperature using the Plackett–Burman design. The optimized conditions by central composite design were 27.83 g/L glucose, 1.32 g/L magnesium sulfate, 26.2°C temperature. The triterpenes fermentation yield with the optimized medium based on actual confirmatory experimental data in 6 L fermentor was 1.076 g/L versus the statistical model predicted value of 1.080 g/L. Our innovatively developed triterpenes fermentation production technology and process has been proven to produce high triterpenes productivity and yield conceivably useful for industrial production.  相似文献   
92.
This investigation was undertaken to ascertain the antinociceptive activity of Caragana microphylla Lam. seeds and isolate and characterize the constituents. Antinociceptive activity was screened using acetic acid-induced abdominal constriction in ICR mice. The 75% ethanol extract and some fractions showed analgesic activity, but the antinociceptive activity of chloroform fraction was the strongest and was more productive than other fractions. Seven compounds were isolated from it and identified as: (1) machaeric acid, (2) beta-sitosterol, (3) stigmasterol, (4) pratol, (5) dehydrocavidine, (6) formononetin and (7) sucrose. Caragana microphylla Lam. seeds showed analgesic activity, with the chloroform fraction showing the strongest analgesic activity among the fractions.  相似文献   
93.
Two of each semisynthetic lanostane‐ and cycloartane‐type triterpenes with a cyano‐enone functionality, i.e., 13 and 18 , and 23 and 28 , respectively, sixteen of their synthetic intermediates, 9 – 12, 14 – 17, 19 – 22 , and 24 – 27 , along with seven semisynthetic oxygenated triterpene acetates, 29 – 35 , and eight natural hydroxy triterpenes, 1 – 8 , were evaluated for their cytotoxic activities against leukemia (HL60), lung (A549), stomach (AZ521), and breast (SK‐BR‐3) cancer cell lines. One natural triterpene, 8 , and ten semisynthetic triterpenes, 9, 13, 15, 18, 23, 25, 28, 29, 32 , and 33 , exhibited potent cytotoxicities against one or more cell lines with IC50 values in the range of 1.4–9.9 μM . Two lanostane‐type triterpenes with a cyano‐enone functionality, 3‐oxolanosta‐1,8,24‐triene‐2‐carbonitrile ( 13 ) and 3‐oxolanosta‐1,8‐diene‐2‐carbonitrile ( 18 ), induced apoptosis in HL60 cells, as observed by membrane phospholipid exposure in flow cytometry. Western blot analysis showed that 13 and 18 significantly reduced procaspases‐3, ‐8, and ‐9, and increased cleaved caspases‐3, ‐8, and ‐9. These findings indicated that compounds 13 and 18 induced apoptosis in HL60 cells via both the mitochondrial and the death receptor‐mediated pathways. In addition, upon evaluation of the inhibitory effects on Epstein? Barr virus early antigen (EBV‐EA) activation induced with 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) in Raji cells, seven natural triterpenes, 1 – 6 and 8 , and ten semisynthetic triterpenes, 9, 10, 14, 15, 19, 20, 24, 25, 29 , and 30 , exhibited inhibitory effects which were higher than that of β‐carotene, a vitamin A precursor studied widely in cancer‐chemoprevention animal models.  相似文献   
94.
Bioassay-guided phytochemical investigation of the EtOAc fraction from the leaves of a Chinese medicinal herb, Eucalyptus citriodora Hook, resulted in the isolation of a new compound rhodomyrtosone E (1), along with 12 known compounds (213). The structure of the new compound was established by 1D and 2D NMR, MS data and X-ray crystallographic analysis. Betulinic acid (2) and corosolic acid (5) increased glucose transporter 4 (GLUT-4) translocation by 2.38 and 1.78-fold, respectively.  相似文献   
95.
The 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced edema model in mice determined the anti-inflammatory activities in vivo of argentatins A, B and D, the main cycloartenol-type triterpenes present in Parthenium argentatum. Our results showed that argentatin B (ED50 = 1.5 × 10−4 mmol/ear) and argentatin A (ED50 = 2.8 × 10−4 mmol/ear) were more potent anti-inflammatory agents than indomethacin (ED50 = 4.5 × 10−4 mmol/ear), the reference drug. Based on these findings, we decided to evaluate 13 derivatives of argentatins A and B. All the derivatives showed anti-inflammatory activity in the TPA-induced edema model in mice. The most active compound was 25-nor-cycloart-3, 16-dione-17-en-24-oic acid, obtained from argentatin A (ED50 = 1.4 × 10−4 mmol/ear). Argentatin B was assayed as inhibitor of COX-2 activity one of the key enzymes involved in the TPA assay. The results showed that argentatin B at 15 μM doses inhibited 77% COX-2 activity. Docking studies suggest that argentatin B interacts with Arg 120, a key residue for COX-2 activity.  相似文献   
96.
Bioassay-guided fractionation of the active BuOH extract of the sea cucumber Pseudocolochirus violaceus resulted in the isolation of three new sulfated triterpene glycosides, i.e., violaceusides I, II, and III (1-3, resp.), as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. Their structures were elucidated by spectroscopic methods including 2D-NMR and MS experiments, as well as chemical evidence. Compounds 1-3 exhibit the same structural features, i.e., the presence of a 16-oxo group in the holostane-type triterpene aglycone with the C(7)=C(8) bond, but differ in the side chains and the tetrasaccharide moieties. Compound 1 possesses one sulfate group, while 2 and 3 are disulfated glycosides. All the glycosides showed significant in vitro cytotoxicities against human gastric cancer MKN-45 and human colon cancer HCT-116 cells.  相似文献   
97.
98.
窄叶鲜卑花的化学成分研究   总被引:3,自引:0,他引:3  
从窄叶鲜卑花(Sibiraeaangustata(Rehd.)Hand-Mazz.)枝叶中分离得到7个结晶,经解析各种光谱数据,分别鉴定为:白桦脂醇(betulinol)(Ⅰ)、灵芝酸Z(ganoderiacidZ)(Ⅱ)、熊果酸(ursolicacid)(Ⅲ)、正三十烷醇(n-triacontanol)(Ⅳ)、正二十四烷酸(n-tetracosanoicacid)(Ⅴ)、二十九烷醇-10(10-nonacosanol)(Ⅵ)、二十二烷醇-10(10-docosanol(Ⅶ).除熊果酸(Ⅲ)外,其它6个化合物均系首次从该植物中获得。  相似文献   
99.
Twenty-one triterpenes consisting of a lupane derivative, two friedelanes, an oleanane derivative, and 17 ursane-type triterpenoids, together with three known triterpenes, three sterols, a fatty acid, a sesquiterpene alkaloid, and a glycerol derivative, were isolated from the stem of Siphonodon celastrineus. Their structures were characterized by various spectroscopic techniques, as well as comparison with literature data. Twenty-seven metabolites of these were evaluated for cytotoxic activity against six human cancer cell lines. The biosynthetic formation of a 1,4-dioxane bridge is also discussed.  相似文献   
100.
Abstract Extracts of Zymomonas mobilis in the presence of NADPH converted tritium-labelled farnesyl diphosphate (FPP) into squalene, resulting from the activity of squalene synthase, as well as diploptene and diplopterol, derived from further squalene cyclisation. An unidentified isoprenoid representing up to 70% of the conversion products of FPP and different from presqualene alcohol was also formed, even in the absence of NADPH. Addition of squalestatin 1, an inhibitor of squalene synthase, blocked biosynthesis from FPP of the three former triterpenes, in accordance with the role of squalene synthase in their formation, as well as that of the unknown compound.  相似文献   
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