title: Pyrrolizidine alkaloids from Echium rauwolfii and Echium horridum (Boraginaceae).
abstract: Echimidine was isolated from Echium rauwolfii and Echium horridum and identified by MS, 1H- and 13C NMR as a major alkaloid. In addition, structures of 12 minor alkaloids were inferred from GLC and GLC-MS analyses: 7-angeloylretronecine, 7-tigloylretronecine, lycopsamine, 7-acetyllycopsamine, uplandicine, 7-angeloyllycopsamine, 7-tigloyllycopsamine, tigloyl isomer of echimidine, 7-angeloyl-9-(2-methylbutyryl)retronecine, 7-tigloyl-9-(2-methylbutyryl)retronecine, 7-angeloyl-9-(2,3-dihydroxybutyryl)retronecine, and 7-tigloyl-9-(2,3-dihydroxybutyryl)retronecine. Both species had similar alkaloid profiles. Alkaloid extracts exhibited antibacterial effects with a MIC of 1.7 mg/ml in E. coli. Microscopic examination of E. coli treated with different subtoxic alkaloid concentrations (13-52 micrograms/ml) revealed extensive filamentation.
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Zagazig University, Egypt.
authors.forename: A
authors.initials: A
authors.lastname: el-Shazly
authors.forename: M
authors.initials: M
authors.lastname: Abdel-All
authors.forename: A
authors.initials: A
authors.lastname: Tei
authors.forename: M
authors.initials: M
authors.lastname: Wink
mesh_terms: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D000935:Antifungal Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D001231:Aspergillus flavus / Q000187:drug effects; D002176:Candida albicans / Q000187:drug effects; D002849:Chromatography, Gas; D008401:Gas Chromatography-Mass Spectrometry; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry*; D011763:Pyrrolizidine Alkaloids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D013045:Species Specificity
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D000935:Antifungal Agents; D010936:Plant Extracts; D011763:Pyrrolizidine Alkaloids