Fig. 5.

Sulfide oxidation by free cells, immobilized cells, and magnetically immobilized cells. The experiments were carried out in the 50-mL centrifuge tube containing 10 mL of 50 mM HEPES buffer (pH 7.4) at 30 °C, 180 rpm. The biomass was equivalent between free cells (OD₆₀₀ of 8) and immobilized cells. NaHS was added to 2 mM to initiate the reaction. a G. oxydans 621H immobilized cells and free cells; b P. putida S16 immobilized cells and free cells. Averages (n ≥ 3) with standard deviations (error bar) were shown