Fig. 3

Volumetric hydrogen productivity (Q_H2) and substrate consumption rate of co-culture of C. kronotskyensis and C. owensensis. Q_H2, bar graph (mmol L⁻¹ h⁻¹) and substrate consumption rate, line graph (mmol L⁻¹ h⁻¹). Case I (without carriers, dotted bar, open circle); Case J (with acrylic fibres, vertical line, open square); Case K (with acrylic fibres and chitosan, diagonal line, open diamond); and Case L (with chitosan, brick, open triangle)