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Kun-young Park - One of the best experts on this subject based on the ideXlab platform.

  • induction of bax and activation of caspases during β sitosterol mediated apoptosis in human colon cancer cells
    International Journal of Oncology, 2003
    Co-Authors: Yung Hyun Choi, Kyu Ri Kong, Keun Ok Jung, Sook Hee Rhee, Kun-young Park
    Abstract:

    : Beta-Sitosterol, a main dietary phytosterol found in plants, may have the potential for prevention and therapy for human cancer. The purpose of the present study was to examine the effect of Beta-Sitosterol on the growth of HT116 human colon cancer cells. Treatment with Beta-Sitosterol resulted in a dose-dependent growth inhibition coupled with the characteristic morphological features of apoptosis and with the increase of a sub-G1 cell population. Apoptosis-inducing concentrations of Beta-Sitosterol induced caspase-3 and caspase-9 activation accompanied by proteolytic cleavage of poly(ADP-ribose)-polymerase. In addition, Beta-Sitosterol-induced apoptosis in HT116 cells was associated with a decreased expression of the anti-apototic Bcl-2 protein and mRNA and a concomitant increase of the pro-apototic Bax protein and mRNA, and with release of cytochrome c from the mitochondria into the cytosol. Beta-Sitosterol treatment also inhibited the expression of cIAP-1 without significant changes in the level of cIAP-2. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of Beta-Sitosterol.

Bhimanagouda S Patil - One of the best experts on this subject based on the ideXlab platform.

  • inhibition of colon cancer cell growth and antioxidant activity of bioactive compounds from poncirus trifoliata l raf
    Bioorganic & Medicinal Chemistry, 2007
    Co-Authors: G K Jayaprakasha, Kranthi K Mandadi, Shibu M Poulose, Y Jadegoud, G Nagana A Gowda, Bhimanagouda S Patil
    Abstract:

    Recently several plant derived natural compounds have been screened for their anticancer activity in order to identify putative compounds with novel structures or mechanism of action. In the present study, fruits of Poncirus trifoliata were extracted with acetone and loaded onto silica gel column chromatography. The column was eluted with different solvents to obtain two bioactive compounds. The purity of compounds was analyzed by HPLC and their structures were identified by 1H and 13C NMR experiments as Beta-Sitosterol and 2-hydroxy-1,2,3-propanetricarboxylic acid 2-methyl ester (HPCME). Beta-Sitosterol, HPCME, and trolox were tested for their antioxidant capacity by oxygen radical absorbance capacity (ORAC) measurement. Further, these compounds were tested for their inhibition of cancer cell proliferation and apoptosis using human colon cancer cell line (HT-29). These results were compared with the corresponding activity on non-cancerous (COS-1 fibroblast) cells. Cell proliferation and induction of apoptosis were determined by MTT assay and nuclear staining. The MTT assay indicated that both the compounds exhibited differential inhibition at various concentrations. Significant arrest of cell growth was observed with Beta-Sitosterol even at low concentration such as 0.63 microM in 48 h and none of the compounds exerted any apparent cytostatic effects on the non-cancerous COS-1 fibroblast cells. Growth inhibition assay suggested the potential use of bioactive compounds as cancer chemopreventive and therapeutic agents. This is the first report on HPCME isolation and identification from Rutaceae family and Beta-Sitosterol from P. trifoliata.

Braz-filho Raimundo - One of the best experts on this subject based on the ideXlab platform.

  • A new natural auaternary indole slkaloid isolated from Tabernaemontana laeta Mart. (Apocynaceae)
    Sociedade Brasileira de Química, 2001
    Co-Authors: Medeiros, Walter L. B., Vieira, Ivo José C., Mathias Leda, Braz-filho Raimundo, Schripsema Jan
    Abstract:

    A new natural quaternary alkaloid, Nb-methylvoachalotine (1), was obtained from the root bark of Tabernaemontana laeta together with three dimeric indole alkaloids, conodurine (2), voacamine (3) and tabernamine (4), and the monomeric indole alkaloids 19S-heyneanine (5), coronaridine (6) and voacangine (7). The known triterpenes alpha-amyrin acetate, beta-amyrin acetate, lupeol acetate and taraxasterol acetate and the phytosterol Beta-Sitosterol and its 3-O-beta-D-glucoside were also identified. The structures of the compounds were elucidated based on spectroscopic studies.Um novo alcalóide quaternário natural, Nb-metilvoachalotina (1), três alcalóides indólicos diméricos, conodurina (2), voacamina (3) e tabernamina (4), e os três alcalóides monoméricos 19S-heyneanina (5), coronaridina (6) e voacangina (7) foram isolados da casca das raízes de Tabernaemontana laeta. Os triterpenos conhecidos 3-O-acetil-alfa-amirina, 3-O-acetil-beta-amirina, 3-O-acetil-lupeol e 3-O-acetiltaraxasterol e os fitoesteróides Beta-Sitosterol e seu derivado 3-O-beta-D-glicopiranosídeo foram também identificados. As estruturas dos compostos foram elucidadas com base na análise de dados espectroscópicos

  • Chemical constituents from roots of Pyrostegia venusta and considerations about its medicinal importance
    Sociedade Brasileira de Química, 2000
    Co-Authors: Ferreira Dalva Trevisan, Alvares Paulo Sérgio M., Houghton Peter J., Braz-filho Raimundo
    Abstract:

    This paper describes the chemical constituents isolated from roots of Pyrostegia venusta. From ethanol extract of the roots allantoin, Beta-Sitosterol, 3b-O-beta-D-glupyranosylsitosterol and hesperedin were isolated. The structures of these natural products were identified on the basis of spectral data, including 2D NMR of the peracetyl derivative of hesperidin

  • Constituintes químicos das raízes de Pyrostegia Venusta e considerações sobre a sua importância medicinal
    Sociedade Brasileira de Química, 2000
    Co-Authors: Ferreira Dalva Trevisan, Alvares Paulo Sérgio M., Houghton Peter J., Braz-filho Raimundo
    Abstract:

    This paper describes the chemical constituents isolated from roots of Pyrostegia venusta. From ethanol extract of the roots allantoin, Beta-Sitosterol, 3b-O-beta-D-glupyranosylsitosterol and hesperedin were isolated. The structures of these natural products were identified on the basis of spectral data, including 2D NMR of the peracetyl derivative of hesperidin

Luciano P. De Queiróz - One of the best experts on this subject based on the ideXlab platform.

  • Constituintes químicos de Ipomoea subincana Meisn. (Convolvulaceae) Chemical constituents of Ipomoea subincana Meisn. (Convolvulaceae)
    Sociedade Brasileira de Química, 2008
    Co-Authors: Marilena Meira, Jorge M. David, Juceni P. David, Sinara V. Araújo, Tatiara L. Regis, Ana Maria Giulietti, Luciano P. De Queiróz
    Abstract:

    The chloroform extract of aerial parts of Ipomoea subincana was submitted to different chromatographic procedures which afforded methyl caffeate, ethyl caffeate, methyl 3,4-dimethoxycinnamate, lupeol, alpha-amyrin, beta-amyrin, 3-beta-O-beta-D-glycopiranosyl-sitosterol, Beta-Sitosterol, stigmasterol, scopoletin, aromadendrane-4beta,10alpha-diol, n-docosyl-cis-p-coumarate and n-icosyl-trans-p-coumarate, vanilin, cinamic acid and vanillic acid. However, from the ethyl acetate extract besides quercetin and 3-O-beta-D-glycopiranosyl-quercetin were isolated methyl 4-O-E-feruloyl-5-O-E-caffeoyl-quinate, methyl 3,5-di-O-E-caffeoyl-quinate and methyl 4-O-E-caffeoyl-quinate. The structures of the compounds were established on the basis of spectral data

  • Constituintes químicos de Ipomoea subincana Meisn. (Convolvulaceae)
    Sociedade Brasileira de Química, 2008
    Co-Authors: David,jorge M., David,juceni P., Regis,tatiara L., Giulietti,ana Maria, Luciano P. De Queiróz
    Abstract:

    The chloroform extract of aerial parts of Ipomoea subincana was submitted to different chromatographic procedures which afforded methyl caffeate, ethyl caffeate, methyl 3,4-dimethoxycinnamate, lupeol, alpha-amyrin, beta-amyrin, 3-beta-O-beta-D-glycopiranosyl-sitosterol, Beta-Sitosterol, stigmasterol, scopoletin, aromadendrane-4beta,10alpha-diol, n-docosyl-cis-p-coumarate and n-icosyl-trans-p-coumarate, vanilin, cinamic acid and vanillic acid. However, from the ethyl acetate extract besides quercetin and 3-O-beta-D-glycopiranosyl-quercetin were isolated methyl 4-O-E-feruloyl-5-O-E-caffeoyl-quinate, methyl 3,5-di-O-E-caffeoyl-quinate and methyl 4-O-E-caffeoyl-quinate. The structures of the compounds were established on the basis of spectral data

Eric Marchioni - One of the best experts on this subject based on the ideXlab platform.

  • identification and quantitative analysis of β sitosterol oxides in vegetable oils by capillary gas chromatography mass spectrometry
    Steroids, 2005
    Co-Authors: Xin Zhang, Diane Juliendavid, Michel Miesch, Philippe Geoffroy, Francis Raul, Stamatiki Roussi, Dalal Aoudewerner, Eric Marchioni
    Abstract:

    As vegetable oils and phytosterol-enriched spreads are marketed for frying food or cooking purposes, temperature is one of the most important factors leading to the formation of phytosterol oxides in food matrix. A methodology based on saponification, organic solvent extraction, solid-phase extraction (SPE), followed by mass spectrometric identification and quantitation of Beta-Sitosterol oxides using capillary gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode was developed and characterized. Relative response factors of six Beta-Sitosterol oxides, including 7alpha-hydroxy, 7beta-hydroxy, 5,6alpha-epoxy, 5,6beta-epoxy, 7-keto, and 5alpha,6beta-dihydroxysitosterol, were calculated against authentic standards of 19-hydroxycholesterol or cholestanol. Linear calibration data, limit of detection, and sample recoveries during analytical process. Recoveries of these oxidation compounds in spiked samples ranged from 88 to 115%, while relative standard derivation (R.S.D.) values were below 10% in most cases. The analytical method was applied to quantify Beta-Sitosterol oxides formed in thermal-oxidized vegetable oils which were heated at different temperatures and for varying time periods. Sitosterol oxidation is strikingly higher in sunflower oil relative to olive oil under all conditions of temperature and heating time.