title: Nematicidal activities of 4-quinolone alkaloids isolated from the aerial part of Triumfetta grandidens against Meloidogyne incognita.
abstract: The methanol extract of the aerial part of Triumfetta grandidens (Tiliaceae) was highly active against Meloidogyne incognita, with second-stage juveniles (J2s) mortality of 100% at 500 μg/mL at 48 h post-exposure. Two 4-quinolone alkaloids, waltherione E (1), a new alkaloid, and waltherione A (2), were isolated and identified as nematicidal compounds through bioassay-guided fractionation and instrumental analysis. The nematicidal activities of the isolated compounds against M. incognita were evaluated on the basis of mortality and effect on egg hatching. Compounds 1 and 2 exhibited high mortalities against J2s of M. incognita, with EC50 values of 0.09 and 0.27 μg/mL at 48 h, respectively. Compounds 1 and 2 also exhibited a considerable inhibitory effect on egg hatching, which inhibited 91.9 and 87.4% of egg hatching, respectively, after 7 days of exposure at a concentration of 1.25 μg/mL. The biological activities of the two 4-quinolone alkaloids were comparable to those of abamectin. In addition, pot experiments using the crude extract of the aerial part of T. grandidens showed that it completely suppressed the formation of gall on roots of plants at a concentration of 1000 μg/mL. These results suggest that T. grandidens and its bioactive 4-quinolone alkaloids can be used as a potent botanical nematicide in organic agriculture.
authors.forename: Ja Yeong
authors.initials: JY
authors.lastname: Jang
authors.forename: Quang Le
authors.initials: QL
authors.lastname: Dang
authors.forename: Yong Ho
authors.initials: YH
authors.lastname: Choi
authors.forename: Gyung Ja
authors.initials: GJ
authors.lastname: Choi
authors.forename: Kyoung Soo
authors.initials: KS
authors.lastname: Jang
authors.forename: Byeongjin
authors.initials: B
authors.lastname: Cha
authors.forename: Ngoc Hoang
authors.initials: NH
authors.lastname: Luu
authors.forename: Jin-Cheol
authors.initials: JC
authors.lastname: Kim
mesh_terms: D042462:4-Quinolones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000470:Alkaloids / Q000302:isolation & purification / Q000494:pharmacology; D000818:Animals; D000969:Antinematodal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D015394:Molecular Structure; D058871:Organic Agriculture; D035261:Plant Components, Aerial / Q000737:chemistry*; D010935:Plant Diseases / Q000469:parasitology / Q000517:prevention & control; D010936:Plant Extracts / Q000494:pharmacology; D032385:Triumfetta / Q000737:chemistry*; D014431:Tylenchoidea / Q000187:drug effects*
chemical_list: D042462:4-Quinolones; D000470:Alkaloids; D000969:Antinematodal Agents; D010936:Plant Extracts