title: Pyrrole alkaloids with potential cancer chemopreventive activity isolated from a goji berry-contaminated commercial sample of African mango.
abstract: Bioassay-guided fractionation of a commercial sample of African mango (Irvingia gabonensis) that was later shown to be contaminated with goji berry (Lycium sp.) led to the isolation of a new pyrrole alkaloid, methyl 2-[2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl]propanoate, 1, along with seven known compounds, 2-8. The structures of the isolated compounds were established by analysis of their spectroscopic data. The new compound 1g showed hydroxyl radical-scavenging activity with an ED50 value of 16.7 μM, whereas 4-[formyl-5-(methoxymethyl)-1H-pyrrol-1-yl]butanoic acid (2) was active in both the hydroxyl radical-scavenging (ED50 11.9 μM) and quinone reductase-induction [CD (concentration required to double QR activity) 2.4 μM)] assays used. The isolated compounds were shown to be absent in a taxonomically authenticated African mango sample but present in three separate authentic samples of goji berry (Lycium barbarum) using LC-MS and (1)H NMR fingerprinting analysis, including one sample that previously showed inhibitory activity in vivo in a rat esophageal cancer model induced with N-nitrosomethylbenzylamine. Additionally, microscopic features characteristic of goji berry were observed in the commercial African mango sample.
authors.affiliation: Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University , 500 West 12th Avenue, Columbus, Ohio 43210, United States.
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Pan
authors.forename: C Benjamin
authors.initials: CB
authors.lastname: Naman
authors.forename: Ye
authors.initials: Y
authors.lastname: Deng
authors.forename: Heebyung
authors.initials: H
authors.lastname: Chai
authors.forename: William J
authors.initials: WJ
authors.lastname: Keller
authors.forename: A Douglas
authors.initials: AD
authors.lastname: Kinghorn
mesh_terms: D000470:Alkaloids / Q000032:analysis* / Q000302:isolation & purification / Q000494:pharmacology; D000818:Animals; D004340:Drug Contamination; D005638:Fruit / Q000737:chemistry*; D032305:Lycium / Q000737:chemistry*; D031022:Mangifera / Q000737:chemistry*; D009369:Neoplasms / Q000517:prevention & control*; D010936:Plant Extracts / Q000032:analysis* / Q000302:isolation & purification / Q000494:pharmacology; D011758:Pyrroles / Q000032:analysis* / Q000302:isolation & purification / Q000494:pharmacology; D051381:Rats
chemical_list: D000470:Alkaloids; D010936:Plant Extracts; D011758:Pyrroles