title: Antiparasitic efficacy of dihydrosanguinarine and dihydrochelerythrine from Macleaya microcarpa against Ichthyophthirius multifiliis in richadsin (Squaliobarbus curriculus).
abstract: Ichthyophthirius multifiliis is a holotrichous protozoan that invades the gills and skin surfaces of fish and can cause morbidity and high mortality in most species of freshwater fish worldwide. The present study was undertaken to investigate the antiparasitic activity of crude extracts and pure compounds from the leaves of Macleaya microcarpa. The chloroform extract showed a promising antiparasitic activity against I. multifiliis. Based on these finding, the chloroform extract was fractionated on silica gel column chromatography in a bioactivity-guided isolation affording two compounds showing potent activity. The structures of the two compounds were elucidated as dihydrosanguinarine and dihydrochelerythrine by hydrogen and carbon-13 nuclear magnetic resonance spectrum and electron ionization mass spectrometry. The in vivo tests revealed that dihydrosanguinarine and dihydrochelerythrine were effective against I. multifiliis with median effective concentration (EC(50)) values of 5.18 and 9.43 mg/l, respectively. The acute toxicities (LC(50)) of dihydrosanguinarine and dihydrochelerythrine for richadsin were 13.3 and 18.2mg/l, respectively. The overall results provided important information for the potential application of dihydrosanguinarine and dihydrochelerythrine in the therapy of serious infection caused by I. multifiliis.
authors.affiliation: Zhejiang Institute of Freshwater Fisheries, Huzhou, Zhejiang 313001, China. yaojiayun@126.com
authors.forename: Jia-yun
authors.initials: JY
authors.lastname: Yao
authors.forename: Zhi-ming
authors.initials: ZM
authors.lastname: Zhou
authors.forename: Xi-lian
authors.initials: XL
authors.lastname: Li
authors.forename: Wen-lin
authors.initials: WL
authors.lastname: Yin
authors.forename: Hong-shun
authors.initials: HS
authors.lastname: Ru
authors.forename: Xiao-yi
authors.initials: XY
authors.lastname: Pan
authors.forename: Gui-jie
authors.initials: GJ
authors.lastname: Hao
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.forename: Jin-yu
authors.initials: JY
authors.lastname: Shen
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology* / Q000627:therapeutic use; D053119:Benzophenanthridines / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use; D001681:Biological Assay / Q000662:veterinary; D016770:Ciliophora Infections / Q000188:drug therapy / Q000469:parasitology / Q000662:veterinary*; D016001:Confidence Intervals; D003530:Cyprinidae / Q000469:parasitology*; D005393:Fish Diseases / Q000188:drug therapy* / Q000469:parasitology; D005880:Gills / Q000469:parasitology; D016803:Hymenostomatida / Q000187:drug effects* / Q000502:physiology; D007546:Isoquinolines / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use; D007928:Lethal Dose 50; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D028101:Papaveraceae / Q000737:chemistry*; D021261:Parasitic Sensitivity Tests / Q000662:veterinary; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D013997:Time Factors
chemical_list: D000981:Antiprotozoal Agents; D053119:Benzophenanthridines; D007546:Isoquinolines; D010936:Plant Extracts; C524982:dihydrochelerythrine; C501843:dihydrosanguinarine