title: Antimicrobial and antiprotozoal activities of secondary metabolites from the fungus Eurotium repens.
abstract: In this study, we examined in vitro antibacterial, antifungal, antimalarial, and antileishmanial activities of secondary metabolites (1-8) isolated from the fungus Eurotium repens. All compounds showed mild to moderate antibacterial or antifungal or both activities except 7. The activity of compound 6 was the best of the group tested. The in vitro antimalarial evaluation of these compounds revealed that compounds 1-3, 5, and 6 showed antimalarial activities against both chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum with IC(50) values in the range of 1.1-3.0 μg/ml without showing any cytotoxicity to the mammalian cells. Compound 5 displayed the highest antimalarial activity. Antileishmanial activity against Leishmania donovani promastigotes was observed for compounds 1-6 with IC(50) values ranging from 6.2 to 23 μg/ml. Antileishmanial activity of compounds 5 and 6 (IC(50) values of 7.5 and 6.2 μg/ml, respectively) was more potent than 1-4 (IC(50) values ranging from 19-23 μg/ml). Compounds 7 and 8 did not show any antiprotozoal effect. Preliminary structure and activity relationship studies indicated that antibacterial, antifungal, antimalarial, and antileishmanial activities associated with phenol derivates (1-6) seem to be dependent on the number of double bonds in the side chain, which would be important for lead optimization in the future.
authors.affiliation: Department of Medicinal Chemistry, School of Pharmacy, The University of Mississippi, Faser Hall 417, University, MS 38677, USA.
authors.forename: Jiangtao
authors.initials: J
authors.lastname: Gao
authors.forename: Mohamed M
authors.initials: MM
authors.lastname: Radwan
authors.forename: Francisco
authors.initials: F
authors.lastname: León
authors.forename: Xiaoning
authors.initials: X
authors.lastname: Wang
authors.forename: Melissa R
authors.initials: MR
authors.lastname: Jacob
authors.forename: Babu L
authors.initials: BL
authors.lastname: Tekwani
authors.forename: Shabana I
authors.initials: SI
authors.lastname: Khan
authors.forename: Shari
authors.initials: S
authors.lastname: Lupien
authors.forename: Robert A
authors.initials: RA
authors.lastname: Hill
authors.forename: Frank M
authors.initials: FM
authors.lastname: Dugan
authors.forename: Horace G
authors.initials: HG
authors.lastname: Cutler
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Cutler