Yazar "Sarker, Satyajit D." seçeneğine göre listele

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    Anti-colon cancer potential of phenolic compounds from the aerial parts of Centaurea gigantea (Asteraceae)
    (Springer Tokyo, 2007) Shoeb, Mohammad; Jaspars, Marcel; MacManns, Stephen M.; Celik, Sezgin; Nahar, Lutfun; Kong-Thoo-Lin, Paul; Sarker, Satyajit D.
    Reversed-phase HPLC analysis of the methanol extract of the aerial parts of Centaurea gigantea afforded chlorogenic acid and five flavonoids, 2-(4'-hydroxybenzoyl)-isoorientin, orientin, isoorientin, isoquercetrin and cirsiliol. The structures of the these phenolic compounds were established unequivocally by UV, MS, a series of 1D and 2D NMR analyses and by comparison of their spectroscopic data with literature data. The free radical scavenging properties of these compounds were assessed by the DPPH assay, and their toxicity towards brine shrimps, and cytotoxicity towards cancer cells were evaluated, respectively, by the brine shrimp lethality assay and the MTT assay using CaCo-2 colon cancer cell line. Among the compounds, chlorogenic acid exhibited considerable anti-colon cancer activity (IC50=79.0 mu M).
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    Bioactivity of two Turkish endemic Centaurea species, and their major constituents
    (Sociedade Brasileira de Farmacognosia, 2007) Shoeb, Mohammad; MacManus, Stephen M.; Jaspars, Marcel; Kong-Thoo-Lin, Paul; Nahar, Lutfun; Celik, Sezgin; Sarker, Satyajit D.
    The antioxidant activity, general toxicity and cytotoxicity of the methanol extracts of Centaurea urvillei subs, armata and C. mucronifera have been assessed, respectively, by the DPPH assay, the brine shrimp lethality and the MTT cytotoxicity assays. The reversed-phase HPLC analysis of the methanol extracts afforded two bioactive dibenzylbutyrolactone-type lignans, matairesinoside (1) and arctiin (2). The structures of these lignans were elucidated by comprehensive spectroscopic analyses as well as by the direct comparison of experimental data with respective literature data.
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    Comparative Study of Antioxidant Properties and Total Phenolic Content of the Extracts of Humulus lupulus L. and Quantification of Bioactive Components by LC-MS/MS and GC-MS
    (Amer Chemical Soc, 2013) Onder, Ferah Comert; Ay, Mehmet; Sarker, Satyajit D.
    In this research, antioxidant activities of various extracts obtained from Humulus lupulus L. were compared by DPPH, ABTS, FRAP, and CUPRAC assays. The amount of total phenolic components determined by the Folin-Ciocalteu reagent was found to be highest for 25% aqueous ethanol (9079 +/- 187.83 mg Ferulic acid equivalent/100 g extract) and methanol-1 (directly) (8343 +/- 158.39 mg Ferulic acid equivalent/100 g extract) extracts. The n-hexane extract of H. lupulus exhibited the greatest with DPPH (14.95 +/- 0.03 mu g Trolox equivalent/g sample). The highest phenolic content in the ethanolic extract could be the major contributor to its highest CUPRAC activity (3.15 +/- 0.44 mmol Trolox equivalent/g sample). Methanol-2 (n-hexane, acetone, and methanol) and methanol-3 (n-hexane, dichloromethane, ethylacetate, and methanol) extracts, respectively, exhibited the most potent ABTS (7.35 +/- 0.03 mM Trolox equivalent) and FRAP (1.56 +/- 0.35 mmol Fe2+/g sample) activities. Some of the components from the crude extracts were determined by LC-MS/MS and GC-MS analyses. Comparative screening of antioxidant activities of H. lupulus extracts and quantification of some major components by LC-MS/MS, qualitatively analysis of the reported ones which were optimal under negative ion SIM mode and coinjection, are going to be valuable for food and health applications.
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    Two salonitenolide derivatives from the aerial parts of Centaurea gigantea inhibit the growth of colorectal cancer cells in vitro
    (Natural Products Inc, 2007) Shoeb, Mohammad; Celik, Sezgin; Nahar, Lutfun; MacManus, Stephen M.; Kong-Thu-lin, Paul; Jaspars, Marcel; Sarker, Satyajit D.
    The cytotoxic activity of two salonitenolide derivatives, 8-O-(3-hydroxy-2-methylpropanoyl)-salonitenolide (or arctiopicrin, 1) and 8-O-(4-hydroxy-3-methylbutanoyl)-salonitenolide,(2), isolated and identified from the methanol extract of the aerial parts of Centaurea gigantea, was assessed by the MTT cytotoxicity assay using the colon cancer cell line, CaCo-2. The IC50 values for 1 and 2 were found to be 8.5 and 26.4 mu M, respectively.
  • Küçük Resim
    Öğe
    Unraveling the role of Globularia species in modern medicine based on evidence from photochemistry, traditional uses and biological activities
    (Elsevier Gmbh, 2025) El-Seedi, Hesham R.; Sabry, Aya; Abolibda, Tariq Z.; Guo, Zhiming; Nahar, Lütfun; Sarker, Satyajit D.; Saeed, Aamer; Karav, Sercan
    Background: Species of the genus Globularia exist in the Mediterranean region spreading upon Macaronesia, northern Europe, and north-eastern Africa. They have valuable biological activities and remarkable phytochemical contents explaining their traditional uses. Purpose: This study reviews phytochemical, pharmacological progress, clinical trials, and molecular mechanisms of action of Globularia extracts and isolated compounds. Study design: In this review the systematic approach is used in summarizing and documenting the information related to Globularia extracts with a special focus on the bioactive component that have numerous biological activities and modes of action. Methods: The relevant information related to the genus Globularia was collected from different databases (SciFinder, Elsevier, PubMed, and Google Scholar) as well as the clinical trials website (https://clinicaltrials.gov/). Results: The genus Globularia consists of 22 species that are used in traditional medicine as laxative, cholagogue, stomachic, purgative, sudorific, antihypertensive, hypoglycemic, carminative, diuretic, and tonic agents. The extracts of these species have biological potentials, for instance, antioxidant, anti-inflammatory, anti-coagulant, anti-diabetes, anti-bacterial, anti-tuberculosis, enzyme inhibitors, wound healing, toxicological, and neuroprotective activity. Among the valuable bioactive phytochemicals are iridoid glycosides, phenylethanoids, and flavonoid glycosides. Conclusion: Despite the efforts made in Globularia isolation there is a lack of knowledge of the biological role of the isolated compounds. Also, the traditional uses of Globularia species are not well-explored and the mechanisms of actions are not investigated thus opening new doors for future efforts in this line.