Bioengineering / Biyomühendislik

Permanent URI for this collectionhttps://hdl.handle.net/11147/4529

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  • Article
    Citation - WoS: 5
    Citation - Scopus: 7
    Five New Cardenolides Transformed From Oleandrin and Nerigoside by Alternaria Eureka 1e1bl1 and Phaeosphaeriasp. 1e4cs-1 and Their Cytotoxic Activities
    (Elsevier Ltd., 2021) Karakoyun, Çiğdem; Küçüksolak, Melis; Bilgi, Eyüp; Doğan, Gamze; Çömlekçi, Yiğit Ege; Bedir, Erdal
    Biotransformation of oleandrin (1) and nerigoside (2) by endophytic fungi; Alternaria eureka 1E1BL1 and Phaeospheria sp. 1E4CS-1, has led to the isolation of five new metabolites (3, 5, 6, 7 and 8) together with a known compound (4). The structures of the biotransformation products were elucidated by 1D-, 2D NMR and HR-MS. Phaeospheria sp. mainly provided monooxygenation reactions on the A and B rings, whereas A. eureka afforded both monooxygenated and desacetylated derivatives of the substrates. Cytotoxic activity of the compounds was tested against a non-cancerous (HEK-293) and four cancer (PANC-1, MIA PaCa-2, DU 145 and A549) cell lines by MTT cell viability assay. All compounds were less cytotoxic than oleandrin, which had IC50 values ranging between 2.7 and 41.9 nM. Two of the monohydroxylated metabolites, viz. 7(?)-hydroxy oleandrin (3) and 1(?)-hydroxy oleandrin (7), were also potent with IC50 values from 18.45 to 39.0 nM, while desacetylated + monohydroxylated, or dihydroxylated products had much lower cytotoxicity. Additionally, the lesser activity of 2 and its metabolite (6) possessing diginose as sugar residue inferred that oleandrose moiety is important for the toxicity of oleandrin as well as hydrophobicity of the steroid core. © 2020 Phytochemical Society of Europe
  • Article
    Citation - WoS: 8
    Citation - Scopus: 9
    Ligand-Based Virtual Screening and Molecular Docking of Two Cytotoxic Compounds Isolated From Papaver Lacerum
    (Elsevier Ltd., 2019) Bayazeid, Omer; Bedir, Erdal; Yalçın, Funda N.
    This study revealed that the Papaver lacerum extract strongly inhibited HeLa cell proliferation, resulting in 13% cell viability. As a result of phytochemical studies, one known compound, Tyrosol-1-O-beta-xylopyranosyl-(1 -> 6)-O-beta-glucopyranoside) (I), and one new compound, 5-O-(6-O-alpha-rhamnopyronosyl-beta-glucopyronosyl) mevalonic acid (II), were isolated. Compounds I and II were found to possess a moderate cytotoxic effect with an IC50 of 66.4 mu M (p < 0.0001) and 54 mu M (p < 0.0001), respectively. The ligand-based virtual screening technique was used to reveal the possible molecular target of compounds I and II. The molecular target was identified as protein-tyrosine kinase Syk for compound I, and aldo-keto reductase family-1 for compound II. Molecular docking was used to assess the binding affinity of the compounds with the targets obtained from ligand-based virtual screening.