Theonellamide G, a Potent Antifungal and Cytotoxic Bicyclic Glycopeptide from the Red Sea Marine Sponge Theonella swinhoei

Marine Drugs

Diaa T. A. Youssef¹  Lamiaa A. Shaala³  Gamal A. Mohamed¹  Jihan M. Badr¹  Faida H. Bamanie² 

[1] Department of Natural Products, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Kingdom of Saudi Arabia; E-Mails:;Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah 21589, Kingdom of Saudi Arabia; E-Mail:;Natural Products Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Kingdom of Saudi Arabia; E-Mail:

关键词: Theonella swinhoei;    glycopeptide;    theonellamide G;    antifungal activity;    cytotoxic activity;   

DOI  :  10.3390/md12041911

来源: mdpi

【 摘 要 】

In our search for bioactive metabolites from marine organisms, we have investigated the polar fraction of the organic extract of the Red Sea sponge Theonella swinhoei. Successive chromatographic separations and final HPLC purification of the potent antifungal fraction afforded a new bicyclic glycopeptide, theonellamide G (1). The structure of the peptide was determined using extensive 1D and 2D NMR and high-resolution mass spectral determinations. The absolute configuration of theonellamide G was determined by chemical degradation and 2D NMR spectroscopy. Theonellamide G showed potent antifungal activity towards wild and amphotericin B-resistant strains of Candida albicans with IC₅₀ of 4.49 and 2.0 μM, respectively. Additionally, it displayed cytotoxic activity against the human colon adenocarcinoma cell line (HCT-16) with IC₅₀ of 6.0 μM. These findings provide further insight into the chemical diversity and biological activities of this class of compounds.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.