Antivibrio compounds produced by Pseudomonas sp W3: characterisation and assessment of their safety to shrimps

作者：Rattanachuay Pattamarat; Kantachote Duang****^*; Tantirungkij Manee; Nitoda Teruhiko; Kanzaki Hiroshi

来源：World Journal of Microbiology and Biotechnology, 2011, 27(4): 869-880.

DOI：10.1007/s11274-010-0529-x

• Antivibrio compounds
• Pseudomonas sp.
• Vibrio harveyi
• Shrimp
• Toxicity

In order to explore compounds naturallly inhibitory to shrimp pathogenic vibrios, a culture filtrate of Pseudomonas sp. W3 at a pH of 2 was extracted with ethyl acetate (EtOAc) to produce 82.15 mg/l of a yellow-brown extract (EtOAc-W3) that had MIC values of 225-450 mu g/ml against the growth of 18 shrimp pathogenic Vibrio harveyi strains. The MIC of EtOAc-W3 against the most pathogenic strain PSU 2015 was 450 mu g/ml and this strain had the lowest LD(50) (50% lethal dose) to pacific white shrimp (Litopenaeus vannamei, PL 21). At this MIC value, EtOAc-W3 in artificial sea water (ASW) killed strain PSU 2015; however in natural sea water, only a partial growth inhibition was observed. The toxicity to pacific white shrimp and antivibrio activity of the EtOAc-W3 were investigated by conducting an experiment with 4 sets; native control (commercial ASW), EtOAc-W3 control (MIC/10, 45 mu g/ml), challenge (inoculation 6.0 x 10(6) c.f.u./ml PSU 2015) and treatment (6.0 x 10(6) c.f.u./ml PSU 2015 + 45 mu g/ml EtOAc-W3). The same experiment was repeated by increasing the dose of EtOAc-W3 to 90 mu g/ml (MIC/5). Both concentrations of EtOAc-W3 tested had no toxicity to postlarval shrimps. A significant decrease in shrimp mortality was observed over a 72 h period as approximately 80% of the shrimps died in each challenge set but only 63 and 23% died in the presence of 45 and 90 mu g/ml EtOAc-W3. The major component of EtOAc-W3 was supposed to be 2-heptyl-4-quinolone (HHQ) by FAB-MS and (1)H-NMR analyses of the purified fraction.

• 出版日期2011-4