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1.
本文综述了苦苣苔科植物的生物活性和三萜类化学成分的研究进展,并找出了从8种苦苣苔科植物中分离得到的27个三萜类化合物的构型规律。  相似文献   

2.
Pentacyclic triterpenoids have wide applications in the pharmaceutical industry. The precise glucosylation at C-3 OH of pentacyclic triterpenoids mediated by uridine 5'-diphospho-glucosyltransferase (UDP-glucosyltransferase [UGT]) is an important way to produce valuable derivatives with various improved functions. However, most reported UGTs suffer from low regiospecificity toward the OH and COOH groups of pentacyclic triterpenoids, which significantly decreases the reaction efficiency. Here, two new UGTs (UGT73C33 and UGT73F24) were discovered in Glycyrrhiza uralensis. UGT73C33 showed high activity but poor regioselectivity toward the C-3 OH and C-30 COOH of pentacyclic triterpenoid, producing three glucosides. UGT73F24 showed rigid regioselectivity toward C-3 OH of typical pentacyclic triterpenoids producing only C-3 O-glucosylated derivatives. In addition, UGT73C33 and UGT73F24 showed a broad substrate scope toward typical flavonoids with various sugar donors. Next, the substrate recognition mechanism of UGT73F24 toward glycyrrhetinic acid (GA) and UDP-glucose was investigated. Two key residues, I23 and L84, were identified to determine activity, and site-directed mutagenesis of UGT73F24-I23G/L84N increased the activity by 4.1-fold. Furthermore, three in vitro GA glycosylation systems with UDP-recycling were constructed, and high yields of GA-3-O-Glc (1.25 mM), GA-30-O-Glc (0.61 mM), and GA-di-Glc (0.26 mM) were obtained. The de novo biosynthesis of GA-3-O-glucose (26.31 mg/L) was also obtained in engineered yeast.  相似文献   

3.
The biological activity of natural and semisynthetic lupane triterpenoids is discussed in a two-part review. The first part is devoted to the pharmacological properties of natural lupane triterpenoids. Betulinic acid has proven to be the most effective antitumor agent among more than fifty natural lupanes.  相似文献   

4.
The discussion of lupane triterpenoids as prospective medicinal preparations is continued, and semisynthetic triterpenoids are being discussed. Acyl derivatives that mainly exhibit high anti-HIV, antitumor, and organoprotective activities are described.  相似文献   

5.
A series of known di- and triterpenoids were characterized in the whole plant of Wedelia buphthaimiflora.  相似文献   

6.
The triterpenoids of Scoparia dulcis were identified as friedelin, glutinol, α-amyrin, betulinic acid, ifflaionic acid and dulcioic acid.  相似文献   

7.
Two morphologically distinct phenotypes of Centella asiatica (Type-1 and Type-2) in South Africa were compared in relation to the levels of triterpenoid saponins with the aim of assessing their potential for biotechnological manipulation of triterpenoid synthesis. The metabolites investigated included madecassoside and asiaticoside and their sapogenins madecassic—and asiatic acid; produced in cultured undifferentiated cells (cell suspensions and calli) and leaves. Weight determination in plant cell suspensions and the accumulation of secondary metabolites after 16 days for Type-1 and 20 days for Type-2 were investigated since these secondary metabolites accumulate during the period that follows the active growth phase. The four triterpenoids of interest were analysed and quantified by HPLC in crude ethanolic extracts. A difference in bioactive triterpenoids was exhibited that was tissue specific and varied between the two phenotypes. The triterpenoids from leaf tissue were more easily quantifiable in each phenotype than in the case of the undifferentiated cells (callus and cell suspensions), which had lower, but still quantifiable, levels of these targeted secondary metabolites. Leaves contained the highest triterpenoid levels (ranging from 1.8 to 5% dry weight for the triterpenoid acids and their glycosides, respectively), with the free acids occurring in a ratio of approximately 1:2.5 in relation to the glycoside content.  相似文献   

8.
The submerged cultivating conditions for triterpenoids production from Antrodia cinnamomea were optimized using uniform design method and the one-factor-at-a-time method was adopted to investigate the effect of plants oils and glucose supply on triterpenoids production and mycelia growth. Corn starch and culturing time were identified as more significant variables for triterpenoids production. The optimal conditions for triterpenoids production was 20.0 g/L corn starch, 20.0 g/L wheat bran, 1.85 g/L MgSO4, initial pH 3 and 16 days of cultivation. In addition, investigation of plant oils and glucose supply showed that 0.3 % (v/v) olive oil supply at the beginning of fermentation stimulated mycelia growth and significantly increased triterpenoids production; 0.2 % (w/v) glucose supplement at 10th day enhanced production of triterpenoids with slight effect on biomass, which is reported for the first time. The triterpenoids production experimentally obtained under the optimal conditions was 7.23 % (w/w). The uniform design method may be used to optimize many environmental and genetic factors such as temperature and agitation that can also affect the triterpenoids production from A. cinnamomea.  相似文献   

9.
Elderberries are used in the preparation of pie, jelly, punch, wine, or liqueur, as well as in many herbal remedies and food supplements. Elderberry products may provide diaphoretic, diuretic, antioxidant, and immunostimulant activities that offer protection against cold and flu. Herein, we report for the first time the qualitative and quantitative evaluation of two isomeric triterpenoids isolated from Sambuci fructus. The analysis revealed that ursolic acid and oleanolic acid are present in Sambuci fructus. The average concentration of ursolic acid was ca. three times higher than the concentration of oleanolic acid. The triterpenoids were detected and quantified using chromatographic methods such as TLC and HPLC. Spectroscopic techniques, including HR‐MS and 2D‐NMR, allowed unequivocal structure determination.  相似文献   

10.
通过单因素实验和正交实验对影响桦褐孔菌三萜提取的异丙醇体积浓度、硫酸铵质量浓度、料液比和超声时间等因素进行探讨,旨在建立桦褐孔菌Inonotus obliquus菌丝体三萜类化合物的提取工艺。结果表明,提取桦褐孔菌三萜的最佳条件为:异丙醇体积浓度40%,硫酸铵质量浓度0.125g/mL,料液比(W/V)0.9:1,超声时间为35min,三萜提取率为6.18%,提取效率明显高于常规超声波提取法(5.38%)。利用该方法获得的三萜具有较强清除自由基的能力。通过正交实验获得的桦褐孔菌三萜的提取工艺是一种经济、有效的方法。  相似文献   

11.
滕李铭  田雪梅  吴芳  戴玉成 《菌物学报》2021,40(7):1811-1819
为探究不同野生灵芝的主要活性成分以及对野生灵芝的开发利用价值,对13种野生灵芝菌株在同一条件下进行液体发酵,采用化学分析的方法,比较菌丝体胞内三萜和多糖的含量差异。结果显示,13种灵芝菌株的三萜和多糖含量有很大差异,其中无柄紫灵芝Ganoderma mastoporum、亮盖灵芝G. lucidum和树舌灵芝G. applanatum的三萜含量较高;树舌灵芝G. applanatum、紫芝G. sinense和褐灵芝G. brownii的多糖含量较高。目前国内广泛栽培灵芝G. lingzhi的野生菌株发酵产物中的三萜和多糖含量并不是最高的,研究结果表明不同种类的野生灵芝还有进一步挖掘的潜在价值。  相似文献   

12.
以不同灵芝品种、不同栽培基质、不同管理方式、不同生长时期获得的灵芝子实体为原料,用95%乙醇超声提取,对提取物进行了含量测定、三萜组成分析和体外抗肿瘤实验。结果表明,不同子实体醇提物中三萜和甾醇类物质的含量在4.60-6.20mg/g之间;高效液相分析发现10种三萜化合物的种类和含量在样品间存在明显差异。所有灵芝子实体醇提物对肿瘤细胞L1210的增殖均有一定的抑制作用,开伞期的灵芝子实体醇提物抑制肿瘤增殖的活性优于其他生长时期。  相似文献   

13.
为准确测定灵芝孢子粉中三萜的含量,运用高效液相建立适合孢子粉的分析测定方法。通过对前处理条件的优化,确定40%乙醇为孢子粉中等极性三萜酸类的最佳提取溶剂,浓缩倍数是子实体提取条件的50倍。通过色谱柱和洗脱条件的优化,建立了包括灵芝酸I、灵芝烯酸C、灵芝酸C2等13种标准品测定方法,方法学考察显示该分析方法精密度、重复性、稳定性的RSD值均小于5%,可以用于灵芝孢子粉中三萜类成分的定量检测。通过5组样品的分析发现,灵芝酸C6、灵芝酸G、灵芝酸A、灵芝酸D、灵芝酸F是灵芝孢子粉中的主要三萜类成分,其中灵芝酸A含量最高,平均占样品三萜总量的比例达19.71%;三萜类成分的溶出量与是否破壁没有相关性。三萜类成分在灵芝孢子粉和灵芝孢子油产品中的含量非常低,孢子粉的三萜含量为14.24-99.70μg/g,仅为子实体的1/100,灵芝孢子油中三萜含量也均低于50μg/g,因此三萜类成分不适合作为灵芝孢子粉及其相关产品的定量检测指标。  相似文献   

14.
樟芝(Antrodia cinnamomea)是一种非褶菌目、多孔菌科的多年生蕈菌类,樟芝子实体中含有多种生理活性物质包括三萜类化合物,但野生樟芝只生长在台湾特有的牛樟树树干腐朽的心材内壁和枯死倒伏的牛樟树表面,生长极其缓慢,很难获得,价格昂贵。本研究的目的是通过液体培养樟芝的菌丝体以产生三萜类化合物,用响应面法优化了樟芝产生三萜类化合物的液体发酵条件。首先对樟芝的液体发酵的培养基成分及培养条件进行了单因素优化,研究发现樟芝液体发酵产生三萜类化合物的最佳碳源和氮源分别为葡萄糖和酵母提取物,最佳浓度分别为100 g/L和9 g/L,优化的培养基配方为(g/L):葡萄糖100.0,酵母提取物9.0,Mg SO4·7H2O 0.5,KH2PO41.0。优化的培养条件为:初始pH值6.0,温度28℃,接种量10%(v/v),摇床转速180 r/min。在此基础上,用响应面法对樟芝液体发酵产生三萜类化合物影响最大的三个因素即碳源、氮源和培养温度进行了优化,结果优化的三种因素条件为:葡萄糖104.71 g/L,酵母提取物9.93 g/L,温度28.42℃。用优化的培养条件液体培养樟芝,其三萜类化合物的产量达到391.45 mg/L,比优化前的产量223.39 mg/L提高了75.23%,为进一步研究液体培养樟芝产生三萜类化合物奠定了基础。  相似文献   

15.
The rare olean-18(19)-ene triterpenoids moradiol and moronic acid were synthesized from betulin, and their antiviral properties were investigated.  相似文献   

16.
The isolation of two coumarins and five triterpenoids from Castanopsis indica is described. These have not been reported from this genus previously. The structures of two of the three new triterpenoids have been elucidated by chemical reactions and physical methods.  相似文献   

17.
基于超高效液相-三重四级杆质谱联用(UPLC-MS/MS)定量检测法优化出一种灵芝三萜热回流提取的工艺。通过本实验建立的灵芝三萜UPLC-MS/MS精确方法检测不同来源的7个栽培品种灵芝子实体中19个三萜化合物的含量,筛选出三萜含量较高的sd-2灵芝子实体作为提取原料,以三萜含量和提取物得率为指标,通过单因素和响应面实验对灵芝三萜的热回流工艺进行优化,获得的最佳条件为:乙醇浓度75%、提取时间2.5h、液料比14:1、提取次数2次。对获得的最佳提取工艺进行中试实验,灵芝子实体乙醇提取物的得率为6.10%,三萜含量为11.8591mg/g。研究结果可为灵芝三萜的工业大规模提取提供理论依据,为灵芝高附加值产品的开发利用提供技术支撑。  相似文献   

18.
Five new (15) and twenty-eight known (633) triterpenoids were isolated from the roots of Ilex asprella. The structures of the new compounds were elucidated by the detailed spectral analysis. The ursane and oleanane triterpenoids were found to show anticomplement activity with some structure-activity relationships. Several triterpenoids (13, 67) exhibited potent anticomplement activity with the CH50 and AP50 values of 0.058–0.131 mg/mL and 0.080–0.444 mg/mL, respectively. It was found that caffeoyl group could enhance activity remarkably, followed by coumaroyl and feruloyl group. The 28-carboxyl group was also important to anticomplement activity for the triterpenoids. However, the triterpenoids with lactone ring (4, 914) exhibited weak activity and triterpenoid glycosides (5, 2333) showed no inhibition. The targets of several bioactive triterpenoids in complement activation cascade were identified as well.  相似文献   

19.
紫芝酸性三萜类化合物体外抑癌和抑菌作用的研究   总被引:2,自引:0,他引:2  
采用噻唑蓝比色(MTT)法研究紫芝酸性三萜对几种癌细胞体外增殖的影响,并用管碟法检测了紫芝胞内酸性三萜对几种细菌和霉菌的体外抑菌作用。结果表明,紫芝胞内酸性三萜和胞外酸性三萜在250μg/mL时,对人肝癌细胞BEL7402和人乳腺癌细胞MCF-7均有显著抑制作用(P<0.05),但对人胃癌细胞SGC-7901没有显著抑制作用(P>0.05)。BEL7402细胞的生长曲线试验表明,胞内酸性三萜组的细胞受到显著抑制,未出现指数增长期,且BEL7402细胞培养3d后,对照组细胞数目多、均匀,而胞内酸性三萜组的细胞数目明显减少,且细胞变小。抑菌试验结果表明,胞内酸性三萜在40mg/mL时,对大肠杆菌Escherichia coli和金黄色葡萄球菌Staphylococcus aureus的生长均具有显著抑制作用(P<0.01),对枯草芽孢杆菌Bacillus subtitis和青霉的Penicillium chrysogenum抑制作用较弱;而在此浓度下对黑曲霉Aspergillus niger没有抑制作用。该样品对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、黑曲霉和青霉的MIC分别为20mg/mL、20mg/mL、40mg/mL、80mg/mL和40mg/mL。此外,该酸性三萜的抑菌成分在60℃下(处理2h)较稳定,但在80℃以上,热稳定性较差,活性降低。  相似文献   

20.
从植物资源、化合物骨架结构、波谱特征及生物活性等方面,综述了国内外报导的38个喹诺酸类型三萜化合物。  相似文献   

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