Fig. 1.

Schematic of integrated fermentation and extraction under supercritical CO₂. A scCO₂-tolerant microbe can be engineered to produce compounds, such as medium-chain alcohols (C4-C5), that may serve as biofuels and may be preferentially extracted from aqueous media into the scCO₂ phase. Collection of scCO₂ followed by partial de-pressurization will facilitate high-purity biofuel extraction. The presented biphasic scCO₂ separation strategy is expected to simultaneously provide a contaminant-free environment for the engineered organism due to the broad microbial lethality of scCO₂, and continuously strip microbially produced biofuels to eliminate end-product toxicity. scCO₂ is only weakly soluble in the aqueous media phase ( < 1%) and vice versa, resulting in a biphasic system