Screening of Marine Bacteria To Synthesize Polyhydroxyalkanoate from Lignin: Contribution of Lignin Derivatives to Biosynthesis by Oceanimonas doudoroffii

To convert lignin and lignin derivatives to biopolyesters, six types of marine bacterial strains were investigated with mineral salt media containing lignin and lignin derivatives. Our results showed that Oceanimonas doudoroffii, which was isolated from an area of the sea polluted with allantoin, directly synthesized polyhydroxyalkanoate (PHA) using lignin or several lignin derivatives as sole carbon sources. Based on the PHA accumulation data, the conversion from lignin to PHA can be carried out mainly via sinapinic acid and syringic acid rather than other lignin derivatives. This is the first study to show the direct microbial conversion from lignin to biopolyester, which will open the door for lignin-based biorefinery applications.