title: Screening and isolation of a nematicidal sesquiterpene from Magnolia grandiflora L.
abstract: The ethanolic extracts from 30 plant species were tested for their nematicidal activity against nematodes Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle and Panagrellus redivivus (L.) Goodey. The leaf extract of Magnolia grandiflora L. exhibited the strongest nematicidal activity against both nematodes, causing 73 and 100% mortality respectively within 48 h at 5 mg mL(-1). A new nematicidal sesquiterpene was obtained from the leaves of M. grandiflora. The compound was determined to be 4,5-epoxy-1(10)E,11(13)-germacradien-12,6-olide, based on spectroscopic methods including 2D NMR techniques. The median lethal concentrations (LC50) of the compound against B. xylophilus and P. redivivus were 71 and 46 mg L(-1) respectively at 48 h. This is the first report of Magnoliaceae species with nematicidal activity.
authors.affiliation: Laboratory for Conservation and Utilization of Bioresources, Yunnan University, Kunming 650091, PR China.
authors.forename: Linjun
authors.initials: L
authors.lastname: Hong
authors.forename: Guohong
authors.initials: G
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.forename: Xinbiao
authors.initials: X
authors.lastname: Wang
authors.forename: Keqin
authors.initials: K
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000969:Antinematodal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*; D031566:Magnolia / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity; D010944:Plants / Q000737:chemistry; D017168:Rhabditida / Q000187:drug effects*; D045788:Sesquiterpenes, Germacrane / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*; D018675:Toxicity Tests; D017187:Tylenchida / Q000187:drug effects*
chemical_list: C519372:4,5-epoxy-1(10)E,11(13)-germacradien-12,6-olide; D000969:Antinematodal Agents; D010936:Plant Extracts; D045788:Sesquiterpenes, Germacrane