A novel 15C compound, pseudoalteromone B ( 1), possessing a novel carbon skeleton, was obtained from a marine bacterium Pseudoalteromonas sp. CGH2XX. This bacterium was originally isolated from a cultured-type octocoral Lobophytum crassum, that was growing in cultivating tanks equipped with a flow-through sea water system. The structure of 1 was established by spectroscopic methods. Pseudoalteromone B ( 1) displayed a modestly inhibitory effect on the release of elastase by human neutrophils.
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[12]
The authors regret that there is an error in pages 1 and 2 of [4] (pages 1675 and 1676 of the issue). In [4], the ubiquinone, pseudoalteromone A, was reported to display an inhibitory effect on the release of elastase (inhibition rate 45.1%) by human nuetrophils at a concentration of 10 μg/mL. However, after detailed collating, we found this data was cited incorrectly. The data (inhibition rate 45.1%) expressed an inhibitory effect of an organic extract from the marine bacterium Pseudoalteromonas sp. CGH2XX on the release of elastase by human nuetrophils as presented in this study. The in vitro anti-inflammatory effects of pseudoalteromone A were tested again. Pseudoalteromone A displayed moderately inhibitory effects on the generation of superoxide anion and the release of elastase (inhibition rates 38.0% and 20.2%) by human neutrophils at a concentration of 10 μg/mL. Diphenyl indonium (DPI) and elastatinal were used as reference compounds in anti-inflammatory activity testing. DPI displayed an inhibitory effect on superoxide anion generation (IC50 = 0.9 μg/mL), and elastatinal exhibited an inhibitory effect on elastase release (IC50 = 31.9 μg/mL) by human neutrophils, respectively. The authors apologize for any inconvenience caused by this error.
