Production of added value bacterial lipids through valorisation of hydrocarbon-contaminated cork waste.

This work demonstrates that cork used as oil-spill sorbents, contaminated with liquid hydrocarbons, herein demonstrated with hexadecane, can be biologically treated by Rhodococcus opacus B4 with concomitant lipids production. R. opacus B4 consumed up to 96% of hexadecane (C16) impregnated in natural and regranulated cork sorbents after 48h incubation, producing 0.59±0.06g of triacylglycerol (TAG) g of C16 consumed with a TAG content of 0.60±0.06gg of cellular dry weight (CDW) and 0.54±0.05g TAG g of C16 consumed with a TAG content of 0.77±0.04gg (CDW), respectively. TAG was mainly composed by fatty acids of 16 and 18 carbon chains demonstrating the feasibility of using it as raw material for biodiesel production. In addition, the obtained lipid-rich biomass (whole cells) can be used for biomethane production, at a yield of 0.4L CH g (CDW). The obtained results support a novel approach for management of oil-spill contaminated cork sorbents through its valorisation by producing bacterial lipids, which can be used as feedstocks for biofuels production.