title: Antimicrobial activities of novel mannosyl lipids isolated from the biocontrol fungus Simplicillium lamellicola BCP against phytopathogenic bacteria.
abstract: The antagonistic fungus Simplicillium lamellicola BCP has been developed as a microbial biopesticide that effectively controls the development of various plant diseases caused by both pathogenic bacteria and pathogenic fungi. Antibacterial bioassay-directed fractionation was used to isolate mannosyl lipids from S. lamellicola BCP, and the structures of these compounds were elucidated using spectral analysis and chemical degradation. Three novel mannosyl lipids were characterized and identified as halymecins F and G and (3R,5R)-3-O-β-D-mannosyl-3,5-dihydrodecanoic acid. Massoia lactone and (3R, 5R)-3-hydroxydecan-5-olide were also isolated from S. lamellicola BCP. The three novel compounds inhibited the growth of the majority of phytopathogenic bacteria that were tested, and halymecin F displayed the strongest antibacterial activity. Agrobacterium tumefaciens was the most sensitive to the three novel compounds, with IC₅₀ values ranging from 1.58 to 24.8 μg/mL. The ethyl acetate extract of the fermentation broth from the antagonistic fungus effectively reduced the bacterial wilt caused by Ralstonia solanacearum on tomato seedlings. These results indicate that S. lamellicola BCP suppresses the development of plant bacterial diseases through the production of antibacterial metabolites.
authors.affiliation: Research Center for Biobased Chemistry, Division of Convergence Chemistry, Korea Research Institute of Chemical Technology , 141 Gajeong-ro, Yuseong-Gu, Daejeon 305-600, Republic of Korea.
authors.forename: Quang
authors.initials: Q
authors.lastname: Le Dang
authors.forename: Teak Soo
authors.initials: TS
authors.lastname: Shin
authors.forename: Myung Soo
authors.initials: MS
authors.lastname: Park
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: In Seon
authors.initials: IS
authors.lastname: Kim
authors.forename: Jin-Cheol
authors.initials: JC
authors.lastname: Kim
mesh_terms: D016960:Agrobacterium tumefaciens / Q000187:drug effects; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D006999:Hypocreales / Q000737:chemistry* / Q000378:metabolism; D008055:Lipids / Q000737:chemistry / Q000494:pharmacology*; D018551:Solanum lycopersicum / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010935:Plant Diseases / Q000382:microbiology* / Q000517:prevention & control; D043368:Ralstonia solanacearum / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D008055:Lipids