Abstract
The CH2Cl2-MeOH extract of the Red Sea sponge Xestospongia sp. afforded two new compounds (1 and 2) and two previously identified C-30 sterols (3 and 4). The chemical structures of the isolated compounds were deduced by examining their NMR and MS spectral data. The antimicrobial activity evaluation of the isolated compounds showed that all the compounds have moderate to good antibacterial effects against the tested bacteria, while compound 1 displayed reasonable activity towards two pathogenic fungi, Aspergillus niger and Candida albicans. Moreover, metabolite 1 has excellent antitumor activities against lymphoma and Ehrlich cell lines with IC50 values of 0.05 and 0.08 mM, respectively. No toxicity was recorded for 1 and 2 (LC50 = 30 mM) against Artemia salina as test organism.