Fig 3. Two-stages cultivation of R. sulfidophilum under microaerobic and photoheterotrophic conditions.

First-stage 520-GM contained 1 μM iron to promote rapid cell growth before reaching stationary growth phase. In second-stage cultivation, cells at Day-3 of first-stage cultivation were harvested by centrifugation and washed once with 2 wt% NaCl solution before added with fresh 520-GM contained 0 μM iron. Biomass (CDM), PHA content and PHA concentration were determined in the second-stage cultivation.