Photo fermentative hydrogen production by a new strain; Rhodobacter sphaeroides CNT 2A, isolated from pond sediment

In the present study, a new purple non sulfur (PNS) bacterial strain identified as Rhodobacter sphaeroides CNT 2A was investigated for photo fermentative hydrogen production from acetate, butyrate (short chain organic acids), glucose & sucrose (simple and complex sugar) as sole carbon source in presence of sodium glutamate (0.6 g/L) as nitrogen source. Initial medium pH, acetate and butyrate concentration (by using these substrates as sole carbon sources) were optimized. At optimum pH 8, hydrogen yield efficiency obtained from acetate and butyrate were 2.1 ± 0.2 mol H2/mole and 2.9 ± 0.2 mol H2/mole substrate consumed, respectively. Hydrogen production obtained from glucose and sucrose were; 0.46 ± 0.05 mol H2/mole and 2.4 ± 0.2 mol H2/mole, respectively. This study imply that CNT 2A encompasses carbohydrate catabolic pathway and thus can utilize carbohydrates (both simple as well as complex sugar) directly.