Abstract
► Microbial production of poly-ethers similar to poly-propylene glycol is reported here for the first time. ► Five poly-ethers A–E with a broad spectrum of biological activities were isolated and partially characterized. ► Poly-ether B prevented both microfouling and macrofouling by the species of bacteria and invertebrate larvae tested at low concentrations. ► Poly-ether D was found to be the PPG2900. ► The optimum production and parallel bioactivity was after a 3-day culturing time.
A sponge-associated bacterium,
Winogradskyella poriferorum strain UST030701-295T was cultured up to 100
l for extraction of antifouling bioactive compounds. Five poly-ethers were isolated and partially characterized based on nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS); two of them showed inhibitory effects on biofilm formation of marine bacteria and larval settlement of macro-foulers but did not produce any adverse effects on the phenotypes of zebra fish embryos at a concentration of 5
μg
ml
−1. The effect of culture duration on the production of the poly-ethers and the bioactivity of the relevant extracts was monitored over a period of 12
days. The total crude poly-ether production increased from day 2 to day 5 and the highest bioactivity was observed on day 3. The poly-ethers were found to be localized in the cellular fraction of the extracts, implying their natural occurrence. The potent bioactivity of these poly-ethers together with their high natural abundance in bacteria makes them promising candidates as ingredients in antifouling applications.