| Resumo: | Nowadays, the replacement of petroleum products by renewable carbon is one of the great concerns in the World. Under this strategy the production of polyhydroxyalkanoates (PHA) starting from a low-cost residue shows with high potential for applications. Combining this with a mixed microbial culture (MMC) with polymer accumulation capacity allows the necessary conditions for the production of PHA at low cost. The main objective of this study was to provide a different valorisation scheme for wood residues considering a new process to be integrated into a global biorefinery approach. Pinewood bio-oil was used as the carbon substrate for the production of PHA in a three-step process: pre-fermentation, culture selection and PHA production, all systems being operated with MMC. In the acidogenic fermentation, several conditions were tested, from which the medium containing 8 g/L of sugars with a C: N: P ratio of 100:3:1 and 10 days of retention time stand out, reaching a maximum short-chain organic acid (SCOA) concentration of 6.3 g/L and an acidification degree of 0.14 gCOD/gCOD. The culture selection reactor operated under aerobic conditions was fed directly with pure bio-oil, reaching a maximum PHA content of 13.93%. Finally, after the adaptation of the culture, accumulation tests were performed in which the maximum PHA content was 35.60%, using fermented bio-oil as a substrate. It was concluded that the pinewood bio-oil is a possible substrate for PHA production.
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