海洋细菌Pseudomonas putida中具有抗硅藻附着的活性成分

Anti-diatom compounds from marine bacterium Pseudomonas putida

【目的】为发现天然的防污损物质,从分离自海绵Haliclona sp.的细菌Pseudomonas putida中寻找具有抗硅藻附着活性的化合物。【方法】综合菌落生长形态、扫描电镜及16S rDNA序列分析,鉴定细菌种属;采用活性(抗硅藻附着)-化学(薄层色谱、二极管阵列高效液相和核磁共振氢谱)导向法对其中的活性组分进行分离纯化,波谱分析确定结构;采用抗硅藻附着活性模型对单体化合物进行活性复筛。【结果】该细菌鉴定为Pseudomonas putida;从其发酵液中分离得到6个环二肽,分别鉴定为环(亮氨酸-脯氨酸)(1)、环(亮氨酸-丙氨酸)(2)、环(苯丙氨酸-丙氨酸)(3)、环(缬氨酸-酪氨酸)(4)、环(丙氨酸-酪氨酸)(5)、环(丙氨酸-色氨酸)(6);化合物3和6在浓度为50μg/mL时具有明显的抑制硅藻附着活性(抑制率分别为50%和85%)。【结论】海洋细菌Pseudomonas putida中具有抗硅藻附着的活性化合物为环(苯丙氨酸-丙氨酸)和环(丙氨酸-色氨酸)。

[ Objective] In order to provide more natural antifouling compounds, marine bacterium Pseudomonas putida isolated from the sponge Haliclona sp. was explored to test its anti-diatom compounds. [ Methods ] The strain was identified by colonial morphology, scanning electron microscope （SEM） and 16S rDNA sequence analysis. The separation procedure was guided by bioactive （Anti-diatom） and chemical （TLC, DAD-HPLCand ^1H NMR） analysis, and their structures were elucidated by spectrographic techniques. The anti-diatom activity of all purified compounds was assayed. [ Results] Strain 272 isolated from the sponge Haliclona sp. was identified as Pseudomonas putida. Six diketopiperazine compounds were isolated from the culture of this strain and their structures were determined as cyclo（Leu-Pro） （ 1 ）, cyclo （Leu-Ala） （ 2 ） , cyclo （Phe-Ala） （ 3 ） , cyclo （Val-Tyr） （4）, cyclo （Ala-Tyr） （5）, cyclo （Ala-Trp） （6） ; Compounds 3 and 6 displayed significant anti-diatom activity with the inhibitory rate of 50% and 85% at the concentration of 50p.g/mL, respectively. [ Conclusion] The anti-diatom compounds isolated from marine bacterium Pseudomonas putida were cyclo （Phe-Ala） and cyclo （Ala-Trp）.