title: Ovicidal activity of lactic acid produced by Lysobacter capsici YS1215 on eggs of root-knot nematode, Meloidogyne incognita.
abstract: Lysobacter capsici YS1215 isolated from soil previously showed nematicidal potential for biological control of the root-knot nematode. In this study, lactic acid, a nematicidal compound, was isolated from culture filtrate of YS1215, and its ovicidal activity was investigated. Purification and identification of lactic acid were performed by a series of column chromatographies and identified by (1)H and (13)C NMR spectra and GC-MS analysis. Our results showed that bacterial culture filtrate containing lactic acid significantly inhibited egg hatching. The lowest egg hatch rate (5.9%) was found at a high concentration (25 μl/ml) of lactic acid at 5 days after incubation, followed by 20 (15.2%), 15 (23.7%), 10 (29.8%), and 5 (36.4%) μl/ml, while egg hatching in the control (sterile distilled water) was 44.5%. This is the first report of lactic acid as an ovicidal compound, and it may be considered as an alternative of chemical pesticide against root-knot nematodes.
authors.affiliation: Division of Applied Bioscience and Biotechnology, Institute of Environmentally-Friendly Agriculture, Chonnam National University, Gwangju 500-757, Republic of Korea.
authors.forename: Yong Seong
authors.initials: YS
authors.lastname: Lee
authors.forename: Kyaw Wai
authors.initials: KW
authors.lastname: Naning
authors.forename: Xuan Hoa
authors.initials: XH
authors.lastname: Nguyen
authors.forename: Sun Bae
authors.initials: SB
authors.lastname: Kim
authors.forename: Jae Hak
authors.initials: JH
authors.lastname: Moon
authors.forename: Kil Yong
authors.initials: KY
authors.lastname: Kim
mesh_terms: D000818:Animals; D000969:Antinematodal Agents / Q000494:pharmacology*; D004625:Embryo, Nonmammalian / Q000187:drug effects* / Q000382:microbiology / Q000502:physiology; D019344:Lactic Acid / Q000378:metabolism* / Q000494:pharmacology; D053528:Lysobacter / Q000378:metabolism*; D014431:Tylenchoidea / Q000382:microbiology*
chemical_list: D000969:Antinematodal Agents; D019344:Lactic Acid