title: Rosmarinic acid from eelgrass shows nematicidal and antibacterial activities against pine wood nematode and its carrying bacteria.
abstract: Pine wilt disease (PWD), a destructive disease for pine trees, is caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus and additional bacteria. In this study, extracts of Zostera marina showed a high nematicidal activity against PWN and some of the bacteria that it carries. Light yellow crystals were obtained from extracts of Z. marina through solvent extraction, followed by chromatography on AB-8 resin and crystallization. The NMR and HPLC analysis showed that the isolated compound was rosmarinic acid (RosA). RosA showed effective nematicidal activity, of which the LC₅₀ (50% lethal concentration) to PWN at 24 h, 48 h and 72 h was 1.18 mg/g, 1.05 mg/g and 0.95 mg/g, respectively. To get a high yield rate of RosA from Z. marina, single factor experiments and an L₉ (3⁴) orthogonal experiment were performed. This extraction process involved 70% ethanol for 3 h at 40 °C. The extraction dosage was 1:50 (w/v). The highest yield of RosA from Zostera was 3.13 mg/g DW (dried weight). The crude extracts of Zostera marina (10 mg/mL) and RosA (1 mg/mL) also showed inhibitory effects to some bacterial strains carried by PWN: Klebsiella sp., Stenotrophomonas maltophilia, Streptomyces sp. and Pantoea agglomerans. The results of these studies provide clues for preparing pesticide to control PWD from Z. marina.
authors.affiliation: Department of Biology, Qingdao University, Qingdao 266071, China.
authors.forename: Jingyu
authors.initials: J
authors.lastname: Wang
authors.forename: Xueru
authors.initials: X
authors.lastname: Pan
authors.forename: Yi
authors.initials: Y
authors.lastname: Han
authors.forename: Daosen
authors.initials: D
authors.lastname: Guo
authors.forename: Qunqun
authors.initials: Q
authors.lastname: Guo
authors.forename: Ronggui
authors.initials: R
authors.lastname: Li
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D000969:Antinematodal Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D002934:Cinnamates / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D003460:Crystallization; D053630:Depsides / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D009348:Nematoda / Q000382:microbiology; D009349:Nematode Infections / Q000188:drug therapy / Q000469:parasitology; D028223:Pinus / Q000382:microbiology / Q000469:parasitology; D010935:Plant Diseases / Q000382:microbiology / Q000469:parasitology; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors; D035962:Zosteraceae / Q000737:chemistry*; D000097123:Rosmarinic Acid
chemical_list: D000900:Anti-Bacterial Agents; D000969:Antinematodal Agents; D002934:Cinnamates; D053630:Depsides; D010936:Plant Extracts; D000097123:Rosmarinic Acid