title: Isoquinoline alkaloids from Macleaya cordata active against plant microbial pathogens.
abstract: Bioassay-guided fractionation of the crude extract of the whole plant of Macleaya cordata R. Br. led to the isolation of four alkaloids, which were identified as sanguinarine (1), chelerythrine (2), protopine (3) and alpha-allocryptopine (4) on the basis of their physicochemical and spectrometric data. Compounds 1 and 2 demonstrated a significant antifungal activity against the six test fungi with median inhibitory concentrations (IC50) ranging from 0.47 to 6.13 microg/mL. Compound 1 was the most effective with an IC50 of 0.47 microg/mL on Rhizoctonia solani. Furthermore, compounds 1 and 2 also demonstrated strong antibacterial activity, with IC50 values ranging from 5.01 to 11.3 microg/mL, and minimum inhibitory concentrations (MIC) ranging from 8.0 to 32.0 microg/mL. This is the first report on the activity of the alkaloids from M. cordata against economically important phytopathogenic fungi and bacteria.
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.forename: Jihua
authors.initials: J
authors.lastname: Wang
authors.forename: Jianglin
authors.initials: J
authors.lastname: Zhao
authors.forename: Shiqiong
authors.initials: S
authors.lastname: Lu
authors.forename: Jingguo
authors.initials: J
authors.lastname: Wang
authors.forename: Weibo
authors.initials: W
authors.lastname: Jiang
authors.forename: Zhanhong
authors.initials: Z
authors.lastname: Ma
authors.forename: Ligang
authors.initials: L
authors.lastname: Zhou
mesh_terms: D000470:Alkaloids / Q000032:analysis* / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000032:analysis / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000235:genetics; D002855:Chromatography, Thin Layer; D005658:Fungi / Q000187:drug effects / Q000254:growth & development; D007202:Indicators and Reagents; D007546:Isoquinolines / Q000032:analysis* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D028101:Papaveraceae / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D000900:Anti-Bacterial Agents; D007202:Indicators and Reagents; D007546:Isoquinolines