title: Bioactive polyketides and alkaloids from Penicillium citrinum, a fungal endophyte isolated from Ocimum tenuiflorum.
abstract: Chemical investigation of the endophytic fungus Penicillium citrinum cultured on white beans or on rice led to the isolation of two new alkaloids (1 and 2), along with fourteen known polyketides (6-12, 14-20) and four known alkaloids (3-5, and 13). The structures of the isolated compounds were determined by extensive analysis of the 1D, 2D NMR, and MS data, and by comparison with the literature. Compound 13, which had been previously obtained only by chemical synthesis, was isolated as a natural product for the first time, while compound 6 was firstly reported as a fungal metabolite. A re-isolation of sclerotinin A (14) revealed it to be a diastereoisomeric mixture (14a and 14b), whose stereochemistry was proposed for the first time based on ROESY experiment. All isolated compounds were evaluated for their cytotoxic and antibacterial activities. Compounds 12 and 17 showed significant cytotoxicity against the murine lymphoma cell line L5178Y with IC50 values of 1.0, and 0.78 μg/ml, respectively, while compounds 5, 11, and 15 were moderately active against Staphylococcus aureus ATCC 29213 (MIC 64 μg/ml).
authors.affiliation: Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University, Universitätsstrasse 1, Geb. 26.23, 40225 Düsseldorf, Germany. Electronic address: laidaowan123@gmail.com.
authors.forename: Daowan
authors.initials: D
authors.lastname: Lai
authors.affiliation: Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University, Universitätsstrasse 1, Geb. 26.23, 40225 Düsseldorf, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Brötz-Oesterhelt
authors.affiliation: Institute of Physiological Chemistry and Pathobiochemistry, Johannes Gutenberg University, Duesbergweg 6, 55128 Mainz, Germany.
authors.forename: Werner E G
authors.initials: WEG
authors.lastname: Müller
authors.affiliation: Helmholtz Centre for Infection Research, Inhoffenstraße 7, D-38124 Braunschweig, Germany.
authors.forename: Victor
authors.initials: V
authors.lastname: Wray
authors.affiliation: Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University, Universitätsstrasse 1, Geb. 26.23, 40225 Düsseldorf, Germany. Electronic address: proksch@uni-duesseldorf.de.
authors.forename: Peter
authors.initials: P
authors.lastname: Proksch
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use; D001688:Biological Products / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D045744:Cell Line, Tumor; D060026:Endophytes / Q000737:chemistry*; D020128:Inhibitory Concentration 50; D008223:Lymphoma / Q000188:drug therapy*; D051379:Mice; D015394:Molecular Structure; D031339:Ocimum / Q000382:microbiology; D010407:Penicillium / Q000737:chemistry*; D061065:Polyketides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D000470:Alkaloids; D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents; D001688:Biological Products; D061065:Polyketides
keywords: Antibacterial activity; Cytotoxicity; Endophyte; Ocimum tenuiflorum; Penicillium citrinum