Bioactive metabolites isolated from the endophytic fungus Penicillium chrysogenum isolated from Red Sea algae

Endophytic fungi constitute one of the most interesting sources of bioactive natural products. They are synergistic to their respective host and at least some of them are thought to play an important role in the host's defence by producing secondary metabolites that protect the host from being attacked by pathogenic fungi [1,2]. Ten known compounds alatinone, emodin, w-hydroxyemodin, 2-Acetylquinazolin-4(3H)-one, chrysophanol, cyclo-L-Alo-L-Leu, cis-cyclo (pro,val), 2',3'-Dihydrosorbicillin, meleagrine, and uracil were identified from the EtOAc-extract of a Czapk's-peptone culture of the endophytic fungus Penicillium chrysogenum isolated from red algae (Liagora viscid (Forsskål) C. Agardh) collected from the Egyptian Red Sea. The structures of the compounds were elucidated on the basis of comprehensive NMR spectral analysis (1H- and 13C- NMR, HHCOSY, HSQC, HMBC) as well as mass spectrometry. The crude organic extract and some of the pure compounds showed moderate to strong antimicrobial activity.

References: [1] Stierle A et al. (1993) Science 260: 214–216. [2] Strobel G et al. (1997) Aust J Bot 45: 1037–1082