title: Antimicrobial activity of sphingolipids isolated from the stems of cucumber (Cucumis sativus L.).
abstract: Three antimicrobial sphingolipids were separated by bioassay-guided isolation from the chloroform fraction of the crude methanol extract of cucumber (Cucumis sativus L.) stems and identified as (2S,3S,4R,10E)-2-[(2'R)-2-hydroxytetra-cosanoylamino]-1,3,4-octadecanetriol-10-ene (1), 1-O-β-D-glucopyranosyl(2S,3S,4R,10E)-2-[(2'R)-2-hydroxy-tetracosanoylamino]-1,3,4-octadecanetriol-10-ene (2) and soya-cerebroside I (3) by their physicochemical properties and spectroscopic analysis. They were evaluated to show antifungal and antibacterial activity on test microorganisms including four fungal and three bacterial species. Among them, compound 1, a relatively low polarity aglycone,  exhibited stronger antimicrobial activity than its corresponding glycoside 2. The results indicated that sphingolipids could be the main antimicrobial compounds in the crude methanol extract of cucumber stems.
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Tang
authors.forename: Xiangjie
authors.initials: X
authors.lastname: Meng
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.forename: Jianglin
authors.initials: J
authors.lastname: Zhao
authors.forename: Ligang
authors.initials: L
authors.lastname: Zhou
authors.forename: Minghua
authors.initials: M
authors.lastname: Qiu
authors.forename: Xianming
authors.initials: X
authors.lastname: Zhang
authors.forename: Zhu
authors.initials: Z
authors.lastname: Yu
authors.forename: Fuyu
authors.initials: F
authors.lastname: Yang
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D001419:Bacteria / Q000254:growth & development*; D018553:Cucumis sativus / Q000737:chemistry*; D005658:Fungi / Q000254:growth & development*; D000432:Methanol / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018547:Plant Stems / Q000737:chemistry*; D013107:Sphingolipids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D010936:Plant Extracts; D013107:Sphingolipids; D000432:Methanol