Phytochemical and biological investigation of Begonia heracleifolia

From the rhizomes of Begonia heracleifolia six known cucurbitacins ( 1- 6) were isolated. Based on spectral data (1D and 2D (1)H-, (13)C-NMR, ESI- and CI-MS) the structures were established as cucurbitacin B ( 1), cucurbitacin D ( 2), 23,24-dihydrocucurbitacin D ( 3), 23,24-dihydrocucurbitacin F ( 4), 2- O-beta-glucopyranosyl-cucurbitacin B ( 5), and 2- O-beta-glucopyranosyl-cucurbitacin D ( 6). Four of them ( 3- 6) were so far not reported as constituents of Begonia spp. Varyingly strong antiproliferative activity towards tumor and immune cells was observed for three compounds ( 1 - 3), due to different structural features.     

Studies on the constituents of trichosanthes root. III. Constituents of roots of Trichosanthes bracteata Voigt

From the fresh roots of Trichosanthes bracteata Voigt., the following substances were identified: methyl palmitate, palmitic acid, suberic acid, alpha-spinasterol, stigmast-7-en-3 beta-ol, alpha-spinasterol 3-O-beta-D-glucopyranoside, stigmast-7-en-3 beta-ol 3-O-beta-D-glucopyranoside, glyceryl 1-palmitate, glyceryl 1-stearate, bryonolic acid, cucurbitacin B, isocucurbitacin B, 3-epi-isocucurbitacin B, 23,24-dihydrocucurbitacin B, 23,24-dihydroisocucurbitacin B, 23,24-dihydro-3-epi-isocucurbitacin B, cucurbitacin D, isocucurbitacin D and D-glucose. This root contains more than 6 times cucurbitacin of the root of T. kirilowii Maxim. var. japonicum Kitam.     

Studies on the constituents of "Trichosanthes root". IV. Constituents of roots of Trichosanthes multiloba Miq., Trichosanthes miyagii Hay. and Chinese crude drug "karo-kon"

A mixture of alpha-spinasterol, stigmast-7-en-3-beta-ol (1) and its 3-O-beta-D-glucopyranoside (2), bryonolic acid (3), 23,24-dihydrocucurbitacin B (4), cucurbitacin B (5), cucurbitacin D (6) were obtained from the fresh roots of Trichosanthes multiloba Miq. (Cucurbitaceae). 1, 2, 4, 5 and 6 were also obtained from the fresh roots of Trichosanthes miyagii Hay. From the chinese crude drug "Karo-Kon", which was considered to be prepared from the roots of Trichosanthes kirilowii Maxim., 1, 2 and 3 were provided.     

Cucurbitacins from Trichosanthes kirilowii as the inhibitory components on tyrosinase activity and melanin synthesis of B16/F10 melanoma cells

Cucurbitacins 1 and 2 were isolated from the root of Trichosanthes kirilowii by tyrosinase inhibitory activity-guided fractionation. Spectroscopic analysis revealed that compounds 1 and 2 were cucurbitacin D and 23,24-dihydro-cucurbitacin D, respectively. Compounds 1 and 2 effectively inhibited the activity of tyrosinase (IC(50) = 0.18 microM and 6.7 microM, respectively), and the synthesis of melanin (IC(50) = 0.16 microM and 7.5 microM, respectively) in B16/F10 melanoma cells.     

New cucurbitacin glycosides from Picrorhiza kurrooa

From the roots of Picrorhiza kurrooa Royle and Benth., seven cucurbitacin glycosides have been isolated and structurally elucidated mainly by NMR and mass spectroscopy. Four of them (4, 5, 6, 7) are new and two, the 2-O-glycoside of cucurbitacin B (25-acetoxy-2-beta-glucosyloxy-16,20-dihydroxy-9-methyl-19-norl anosta-5, 23-diene-3,11,22-trione) and the 2-O-glucoside of 23,24 didydrocucurbitacin B (25-acetoxy-2-beta-glucosyloxy-16,20-dihydroxy-9-methyl-19-norl anost-5-ene-3, 11-22-trione) were so far not reported as constituents of this plant. The four new cucurbitacins could be identified as 2-beta-glucosyloxy-3,16,20,25-tetrahydroxy-9-methyl-19-norlanos ta-5, 23-diene-22-one, 2-beta-glucosyloxy-3,16,20,25-tetrahydroxy-9-methyl-19-norlanos t-5-ene-22-one, the 2-O-glucoside of cucurbitacin Q (25-acetoxy-2-beta-glucosyloxy-3,16,20-trihydroxy-9-methyl-19-n orlanosta-5, 23-diene-11,22-dione), and the 2-O-glucoside of deacetoxycucurbitacin B (2-beta-glucosyloxy-16,20-dihydroxy-9-methyl-19-norlanosta-5 , 24-diene-3,11,22-trione).     

甜瓜蒂化学成分的分离与鉴定

目的研究甜瓜蒂的化学成分。方法采用硅胶、ODS、凝胶、制备HPLC等多种色谱方法分离纯化,根据理化性质、波谱数据分析对分离得到的化合物进行结构鉴定。结果从甜瓜蒂中分离得到了7个化合物,分别鉴定为:粘霉烯醇(glutinol,1)、葫芦素B(cucurbitacin B,2)、葫芦素B-2-O-β-D-葡萄糖苷(2-O-β-D-glucopyranosy cucurbitacin B,3)、葫芦素D(cucurbitacin D,4)、(6S,9S)6-羟基-3-酮-α-紫罗兰醇-9-O-β-D-葡萄糖苷[(6S,9S)6-hydroxyl-3-oxo-α-ionol-9-O-β-D-glucopyranoside,5]、尿嘧啶核苷(uridine,6)和β-D-葡萄糖乙苷(ethyl-β-D-glucopyranoside,7)。结论化合物1、5、7均为首次从甜瓜属植物中分离得到,化合物6为首次从甜瓜蒂植物中分离得到。     

细花雪胆中的新成分——新葫芦素

本文报告从细花雪胆(Hemsleya graciliflora(Harms)cogn)地下茎中分离鉴定了五个化合物Ⅰa,Ⅰb,Ⅱa,Ⅱb和Ⅲ。经UV,IR,¹HNMR,MS分析及催化氢化证明Ia是一个新葫芦素:19-失碳,9β-甲基,10 α-H,2β,3α,16α,20,25-五羟基,△^5,23-羊毛甾二烯,11,22-双酮,25-乙酸酯即葫芦素F-25-乙酸酯(cucurbitacin F-25-acetate)。Ib是雪胆甲素(23,24-dihydrocucurbitacin F-25-acetate)。Ⅱa是葫芦素F(cucurbitacin F)。Ⅱb是雪胆乙素(23,24-dihydro-cucurbitacin F)。Ⅲ是齐墩果酸-28-O-β-D吡喃葡萄糖甙(C₂₈-glucoside of oleanoIic acid)。     

Studies on the constituents of trichosanthes root. I. Constituents of roots of Trichosanthes kirilowii Maxim. var. japonicum Kitam

From the fresh roots of Trichosanthes kirilowii Maxim. var. japonicum Kitam., the following substances were identified: methyl palmitate, palmitic acid, suberic acid, alpha-spinasterol, stigmast-7-en-3 beta-ol, alpha-spinasterol 3-O-beta-D-glucopyranoside, stigmast-7-en-3 beta-ol 3-O-beta-D-glucopyranoside, bryonolic acid, cucurbitacin B, cucurbitacin D, vomifoliol, ethyl alpha-L-arabinofranoside and D-glucose. The bitter taste of Trichosanthes Root was considered to be due to cucurbitacin B and D.     

外翻肠囊法研究姜黄素促进葫芦素B肠段吸收作用

目的:建立大鼠肠吸收模型,考察对葫芦素B的吸收以及姜黄素对葫芦素B吸收的促进作用。方法:采用大鼠离体外翻肠囊模型,通过HPLC法测定肠囊内样品溶液中葫芦素B的含量,研究葫芦素B在不同肠段的吸收特性和不同比例姜黄素对葫芦素B的促吸收作用。结果:葫芦素B的肠吸收随其浓度的升高而增大,当葫芦素B联合不同比例姜黄素后,百分吸收率(P%)、累计吸收量(Q)和吸收速率常数K_a值均具有显著性差异。结论:葫芦素B主要吸收部位为十二指肠,且在大鼠肠内主要以被动扩散方式吸收;姜黄素能够促进葫芦素B的大鼠肠吸收,且呈浓度依赖性。     

Antitumor activity ofTrichosanthes kirilowii

The activity-directed fractionation upon the MeOH extract of the root ofTrichosanthes kirilowii led to the isolation of eight cucurbitane triterpenes namely cucurbitacin B (I), isocucurbitacin B (II), cucurbitacin D (III), isocucurbitacin D (IV), 3-epi-isocucurbitacin B (V), dihydrocucurbitacin B (VI), dihydroisocucurbitacin B (VII) and dihydrocucurbitacin E (VIII), as active principles. All isolates were shown to exhibit significant cytotoxicity against cultured human tumor cells, including A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT 15, with an exceptionally high potency.     

Cogniauxia podolaena: bioassay-guided fractionation of defoliated stems, isolation of active compounds, antiplasmodial activity and cytotoxicity

COGNIAUXIA PODOLAENA Baill. (Cucurbitaceae) is traditionally used in Congo Brazzaville for the treatment of malaria. We assessed the antiplasmodial activity of the plant and isolated some of the compounds responsible for this activity. It was the first time that a chemical study of this plant has been undertaken. Three triterpenes were isolated: cucurbitacin B ( 1), cucurbitacin D ( 2) and 20-epibryonolic acid ( 3) and their structures were assigned from spectroscopic evidence and comparison with published data. The crystallographic structure of 3 was determined. All fractions and compounds obtained in this study were assayed for antiplasmodial activity (on FcM29, a chloroquine-resistant strain of P. FALCIPARUM) and cytotoxicity (on KB and Vero cell lines). The IC50 values of 1, 2 and 3 are 1.6, 4 and 2 microg/mL on FcM29. Both 1 and 2 have a high cytotoxicity whereas 3 shows a better selectivity index.     

Growth inhibitory activity of cucurbitacin glucosides isolated from Citrullus colocynthis on human breast cancer cells

Our aim was to study the effects of cucurbitacin glucosides extracted from Citrullus colocynthis leaves on human breast cancer cell growth. Leaves were extracted, resulting in the identification of cucurbitacin B/E glucosides. The cucurbitacin glucoside combination (1:1) inhibited growth of ER(+) MCF-7 and ER(-) MDA-MB-231 human breast cancer cell lines. Cell-cycle analysis showed that treatment with isolated cucurbitacin glucoside combination resulted in accumulation of cells at the G(2)/M phase of the cell cycle. Treated cells showed rapid reduction in the level of the key protein complex necessary to the regulation of G(2) exit and initiation of mitosis, namely the p34(CDC2)/cyclin B1 complex. cucurbitacin glucoside treatment also caused changes in the overall cell morphology from an elongated form to a round-shaped cell, which indicates that cucurbitacin treatment caused impairment of actin filament organization. This profound morphological change might also influence intracellular signaling by molecules such as PKB, resulting in inhibition in the transmission of survival signals. Reduction in PKB phosphorylation and inhibition of survivin, an anti-apoptosis family member, was observed. The treatment caused elevation in p-STAT3 and in p21(WAF), proven to be a STAT3 positive target in absence of survival signals. Cucurbitacin glucoside treatment also induced apoptosis, as measured by Annexin V/propidium iodide staining and by changes in mitochondrial membrane potential (DeltaPsi) using a fluorescent dye, JC-1. We suggest that cucurbitacin glucosides exhibit pleiotropic effects on cells, causing both cell cycle arrest and apoptosis. These results suggest that cucurbitacin glucosides might have therapeutic value against breast cancer cells.     

Cucurbitacin D isolated from Trichosanthes kirilowii induces apoptosis in human hepatocellular carcinoma cells in vitro

The aim of the present study is to examine the effects of the anti-tumor component isolated from Trichosanthes kirilowii on human hepatocellular carcinoma cells. Using Sephadex G-25 column chromatography, Sep-Pak Plus C18 cartridge and high-performance liquid chromatography (HPLC), we isolated the active component from trichosanthes extract. By fast atom bombardment mass spectrometric analysis, the molecular mass of the active fraction was determined, the active components identified, and their mechanisms of action were analyzed by cell growth assay, cell cycle analysis, TUNEL staining and Western blot analysis. We found that the anti-tumor components isolated from the extract of trichosanthes (EOT) are cucurbitacin D and dihydrocucurbitacin D, and suggest that cucurbitacin D induces apoptosis through caspase-3 and phosphorylation of JNK in hepatocellular carcinoma cells. These results suggest that cucurbitacin D isolated from Trichosanthes kirilowii could be a valuable candidate for anti-tumor drug.     

Anti-inflammatory activity of two cucurbitacins isolated from Cayaponia tayuya roots

Fractionation of an anti-inflammatory extract from Cayaponia tayuya roots yielded two active compounds, identified as 23,24-dihydrocucurbitacin B (1) and cucurbitacin R (2). Both were evaluated for their anti-inflammatory activity on several experimental models of pain and inflammation. In addition, their cytotoxicity and effects on leukotriene B4 (LTB4) formation were evaluated in rat polymorphonuclear leukocytes. Both compounds showed activity in the following models: carrageenan-induced mouse paw oedema (1, 4 mg/kg p.o., 46% inhibition at 3 h), phospholipase A2-induced mouse paw oedema (2, 3 mg/kg i.p., 61% inhibition at 60 min), serotonin-induced mouse paw oedema (1 and 2, 0.5 mg/kg s.c., 73% and 79% inhibition, respectively), 12- O-tetradecanoylphorbol 13-acetate (TPA)-induced acute ear oedema (2, 36% inhibition at 4 mg/kg p.o., and 87% inhibition at 0.1 mg/ear topically). The compounds were also active against the inflammation induced by repeated application of TPA on mouse ears, affecting both the oedema itself (1 and 2 at 0.1 mg/ear, 44% and 56% inhibition, respectively) as well as cell infiltration (68% and 69%, respectively). The activity of both compounds against oedema induced by serotonin was not modified by the glucocorticoid receptor antagonist mifepristone; however, the protein synthesis inhibitor cycloheximide abolished the anti-inflammatory response in both cases. Neither compound modified the production of LTB4 in rat polymorphonuclear leukocytes, nor did they exhibit analgesic properties at the dose assayed.     

HPLC法同时测定葫芦素原料中葫芦素B和葫芦素E的含量

目的建立同时测定葫芦素原料中葫芦素B和葫芦素E含量的方法。方法采用HPLC法。色谱柱为Diamonsil C18柱(200 mm×4.6 mm,5μm),流动相为乙腈-水-冰醋酸(体积比50∶50∶0.1),流速为1.0 mL.min-1,柱温为室温,检测波长为234 nm,进样量为20μL。结果葫芦素B和葫芦素E质量浓度分别在28.2~253.8 mg.L-1和2.02~18.18 mg.L-1内与峰面积呈良好的线性关系,平均回收率分别为100.1%(RSD=1.0%,n=9)和99.5%(RSD=0.83%,n=9)。结论该方法快速、准确、重复性好,能更好的控制葫芦素原料的质量。     

Plant anticancer agents. XXX: Cucurbitacins from Ipomopsis aggregata (Polemoniaceae)

Isocucurbitacin B (I), 3-epi-isocucurbitacin B (II), and cucurbitacin B (III) were identified as the principal cytotoxic constituents of Ipomopsis aggregata (Pursh) V. Grant (Polemoniaceae). The structure of the new compound, II, was determined through analysis of its spectrometric characteristics.     

白英中两个新糖苷生物碱

对中药白英的生物碱类成分进行研究.采用ODS、硅胶柱层析和高效液相色谱相结合的方法对生物碱进行分离纯化.通过UHPLC-ESI-Q-TOF-MS、 1D和2D NMR鉴定了7个生物碱类化合物,分别为15β-ethoxy-(3β,5a,25R)-16,23-epoxy-23,24-imino-cholestan-16,2...     

Cucurbitacin B, a small molecule inhibitor of the Stat3 signaling pathway, enhances the chemosensitivity of laryngeal squamous cell carcinoma cells to cisplatin

We have previously shown that the simultaneous exposure of Hep-2 cells to cucurbitacin B and docetaxel significantly enhances anticancer activity of these cells by suppressing Stat3 activation and down-regulating the expression levels of key cell cycle and anti-apoptosis regulators. In order to determine whether cucurbitacin B can also enhance the sensitivity of Hep-2 laryngeal cells to cisplatin, we treated Hep-2 cells with either cucurbitacin B, cisplatin, or the combination and evaluated these cells for proliferation, cell cycle distribution, and apoptosis. Our results demonstrate that, in comparison to single agent cucurbitacin B or cisplatin treated cells, Hep-2 cells treated with a cucurbitacin B/cisplatin combination display synergistic effects on growth inhibition, cell cycle arrest, and apoptosis induction. Western blot analysis using protein extracts from Hep-2 cells treated with cucurbitacin B, cisplatin, or the combination largely recapitulated the observations made when treated with the cucurbitacin B/docetaxel combination. More specifically, Hep-2 cell lines treated with the cucurbitacin B/cisplatin combination demonstrated a significantly reduced level of p-Stat3 in comparison with single agent treated cells. In addition, cucurbitacin B/cisplatin treated Hep-2 cells also demonstrated a significant reduction in Bcl-2 and Cyclin B1 protein levels compared to single agent cucurbitacin B or cisplatin treated cells. Xenograft models containing Hep-2 cells in mice also demonstrated that this cucurbitacin B/cisplatin combination led to the synergistic inhibition of tumor growth. Taken together, these results suggest that the cucurbitacin B/cisplatin combination treatment may be a potentially useful therapeutic option for individuals diagnosed with laryngeal cancer.