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121.
The chemical study of Eugenia protenta McVaugh extracts performed by classical and high-performance liquid chromatography techniques and spectral methods has led to the identification of known triterpenoids, flavonoids and an acetophenone derivative (dimethylxanthoxylin). The effect of dimethylxanthoxylin on Leishmania (Leishmania) amazonensis was evaluated against the promastigotes forms after 96 h of treatment. Dimethylxanthoxylin reduced 57 and 59% of the promastigotes growth when treated with 50 and 100 μg/mL solutions, respectively (IC50 117.35 μg/mL or 52.3 μM). Cytotoxicity experiments using MTT assays showed that this substance did not promote cell death after 24 h of treatment. Dimethylxanthoxylin was active on the promastigotes and could be a promising agent for treating leishmaniasis.  相似文献   
122.
乌骨藤中五环三萜类化合物的分离鉴定   总被引:2,自引:0,他引:2  
利用硅胶柱色谱法、Sephadex LH-20凝胶柱色谱法及半制备高效液相色谱法,从乌骨藤的正丁醇萃取物中分离得到4种五环三萜类化合物。利用核磁共振谱、质谱、红外光谱等分析方法对化合物结构进行了分析和表征,确定了4种化合物分别为β-香树脂醇(β-amyrin)、白桦酯醇(betulin)、白桦酯酸(betulinic acid)和羽扇豆醇(lupeol),它们为首次在牛奶菜属植物中发现,其中后3种化合物具有抗肿瘤活性。  相似文献   
123.
Cranberries are used in the production of medicinal preparations and food supplements, which highlights the importance of triterpene compounds determination in cranberry fruit raw material. The aim of our study was to develop and validate for routine testing suitable UPLC-DAD methodology for the evaluation of triterpene acids, neutral triterpenoids, phytosterols, and squalene content in cranberry samples. The developed and optimized UPLC-DAD methodology was validated according to the guidelines of the International Council for Harmonization (ICH), evaluating the following parameters: range, specificity, linearity (R2 > 0.999), precision, LOD (0.27–1.86 µg/mL), LOQ (0.90–6.18 µg/mL), and recovery (80–110%). The developed and validated technique was used for the evaluation of triterpenic compounds in samples of Vaccinium macrocarpon and Vaccinium oxycoccos fruits, and their peels, pulp and seeds. The studied chromatogram profiles of Vaccinium macrocarpon and Vaccinium oxycoccos were identical but differed in the areas of the analytical peaks. Ursolic acid was the dominant compound in fruit samples of Vaccinium macrocarpon and Vaccinium oxycoccos. The highest amounts of triterpenic compounds were detected in the cranberry peels samples. The developed method for the detection of triterpene compounds can be applied in further studies for routine testing on the qualitative and quantitative composition of fruit samples of Vaccinium macrocarpon and Vaccinium oxycoccos species and cultivars.  相似文献   
124.
Nowadays, amaranth is a valuable multipurpose crop and a source of a number of very important biologically active substances. The aim of this study was to develop a comprehensive scheme for obtaining fatty oil, triterpenoids and lectin from the seeds of Amaranthus caudatus L. in one technological cycle. Two variants of the lectin and triterpene compound purification method from amaranth seeds were tested. It was determined that the extraction of triterpene compounds should be carried out after purification of the lectin from degreased seeds. The rationality of this sequence of technological operations is explained by the lability of the lectin and the insolubility in water of triterpene compounds from amaranth seeds. The study also presents a scheme for obtaining squalene from amaranth oil by chromatography on silica gel and proposes a more effective affinity sorbent for purification of the lectin. The use of such a sorbent also opens up the possibility of preserving other water-soluble substances from amaranth seeds. The physicochemical characteristics and carbohydrate specificity of the lectin are described and new data on the results of the interaction of lectin with human and animal erythrocytes are given. The obtained results are discussed in the light of the complex use of raw materials.  相似文献   
125.
Ginseng is one of the most widely consumed herbs in the world and plays an important role in counteracting fatigue and alleviating stress. The main active substances of ginseng are its ginsenosides. Ocotillol-type triterpenoid is a remarkably effective ginsenoside from Vietnamese ginseng that has received attention because of its potential antibacterial, anticancer and anti-inflammatory properties, among others. The semisynthesis, modification and biological activities of ocotillol-type compounds have been extensively studied in recent years. The aim of this review is to summarize semisynthesis, modification and pharmacological activities of ocotillol-type compounds. The structure–activity relationship studies of these compounds were reported. This summary should prove useful information for drug exploration of ocotillol-type derivatives.  相似文献   
126.
One novel and eight known oxidatively rearranged cycloartane triterpenoids were isolated from the seeds of Pseudolarix amabilis. The structure of the new isolate was elucidated on extensive spectroscopic analyses. Results indicated that pseudolarolide Q (4) exhibited strong antimicrobial activity against Gram-positive Staphylococcus aureus and Candida albicans at the MICs of 6.08 and 24.32 μM, respectively. Pseudolarolide I (2) showed the 11β-HSD1 inhibitory property at the IC50 value of 34.5 nM.  相似文献   
127.
The geographic impact on the quality of Alismatis Rhizoma (derived from the tuber of Alisma orientale), a reputable diuretic traditional Chinese medicine, has seldom been evaluated. Here a metabolomics‐driven approach targeting the bioactive protostane triterpenes was developed, by incorporating UHPLC with quadrupole time‐of‐flight mass spectrometry‐based untargeted metabolite profiling and multiple reaction monitoring quantitative assay, to probe the triterpene differences between Alismatis Rhizoma samples collected from Sichuan, Fujian, and Jiangxi Provinces. Following the metabolomics workflows, the samples from Sichuan and Jiangxi displayed distinct differences in their triterpene profiles, whereas those from Fujian showed remarkable intra‐class variation. Twenty‐three triterpenes were identified to contribute most to the differentiated clustering. A sensitive, precise, repeatable, and accurate quantitative assay method was established on a hybrid triple quadrupole‐linear ion trap mass spectrometer to quantify the contents of eight triterpene compounds. Taking into account the metabolomics and quantitation results, alisol B 23‐acetate and alisol A are significantly different in Alismatis Rhizoma from Sichuan and Jiangxi Provinces, and they may have the potential for geographic discrimination. These results illustrate how geographic difference impacts the triterpene chemistry of Alismatis Rhizoma. Metabolomics‐driven chemical comparison is suitable for the quality evaluation of traditional Chinese medicine.  相似文献   
128.
The new cycloartane glycoside cycloorbicoside D, which has the structure 23ξ,24ξ-cycloartan-3β6α,16β,23,24,25-hexaol 3-O-β-D-xylopyranoside, was isolated from the aerial part of Astragalus orbiculatus Ledeb. (Leguminosae). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 345–346, July–August, 2005.  相似文献   
129.
Three new cyclolanostane triterpenoids, 1 – 3 , were isolated from the EtOH extract of the stems of Kadsura heteroclita. Their structures and configurations were determined by extensive 1D‐ and 2D‐NMR spectroscopy, high‐resolution mass spectrometry (HR‐MS), and circular dichroism (CD) spectroscopy. The three new compounds are likely to be artificial products formed during the extraction process, and might be derived from schisanlactone E ( 4 ) and two related double‐bond isomers, respectively.  相似文献   
130.
A simple and accurate method coupling high-performance liquid chromatography–evaporative light scattering detector was developed to simultaneously quantify the five triterpenoids in different parts of Aralia elata (Miq.) Seem (A. elata). for the first time. Samples were extracted using 70% methanol by ultrasonication. Separation of the analytes was performed on a Welchrom C18 column with acetonitrile and water as the mobile phase. All calibration curves had good linearity over relatively wide range of concentrations. This method showed good average recovery and precision, also high sensitivity with limits of detection and quantification. This method was successfully applied to quantify triterpenoid saponins in 14 samples collected from different areas of China. This study demonstrate that there is significant variation in the amounts of the five triterpenoids of interest in A. elata. Furthermore, 70% methanol extracts of roots had the strongest effect on ox-low-density lipoprotein-induced human umbilical vein endothelial cell apoptosis.  相似文献   
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