title: Identification of orfamide A as an insecticidal metabolite produced by Pseudomonas protegens F6.
abstract: The use of biosurfactants for agricultural crop protection has been gaining interest because they are generally biodegradable and environmentally friendly. In the present study, we identified an insecticidal biosurfactant produced by Pseudomonas protegens F6 (F6) and examined its use for aphid control. The growth of F6 was accompanied by increased aphid mortality and decreased water surface tension. Bioassay-guided chromatography coupled with instrumental analyses, nuclear magnetic resonance (NMR), and time-of-flight mass spectrometer (TOF MS) identified orfamide A as a major metabolite that showed insecticidal activity against green peach aphid ( Myzus persicae ). Orfamide A revealed a dose-dependent mortality against aphids, producing a LC50 value at 34.5 μg/mL, and caused a considerable decrease in the surface tension value of water, giving about 35.7 mN/m at 10 μg/mL. Laboratory and greenhouse mortality bioassays suggested that orfamide A may be applicable to control aphids in organic agriculture. This is the first report of orfamide A as an insecticidal metabolite against Myzus persicae .
authors.affiliation: Divison of Applied Bioscience and Biotechnology, Institute of Environmentally friendly Agriculture, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500-757, Republic of Korea.
authors.forename: Ja Yeong
authors.initials: JY
authors.lastname: Jang
authors.forename: Si Young
authors.initials: SY
authors.lastname: Yang
authors.forename: Young Cheol
authors.initials: YC
authors.lastname: Kim
authors.forename: Chul Won
authors.initials: CW
authors.lastname: Lee
authors.forename: Myung Soo
authors.initials: MS
authors.lastname: Park
authors.forename: Jin Cheol
authors.initials: JC
authors.lastname: Kim
authors.forename: In Seon
authors.initials: IS
authors.lastname: Kim
mesh_terms: D000818:Animals; D001042:Aphids; D004305:Dose-Response Relationship, Drug; D007300:Insect Control; D007306:Insecticides / Q000378:metabolism*; D055666:Lipopeptides / Q000008:administration & dosage / Q000032:analysis* / Q000378:metabolism; D058871:Organic Agriculture; D010456:Peptides, Cyclic / Q000008:administration & dosage / Q000032:analysis* / Q000378:metabolism; D011549:Pseudomonas / Q000378:metabolism*; D013500:Surface Tension / Q000187:drug effects; D013501:Surface-Active Agents / Q000378:metabolism*
chemical_list: D007306:Insecticides; D055666:Lipopeptides; D010456:Peptides, Cyclic; D013501:Surface-Active Agents; C585331:orfamide A