Hydrogen-producing purple non-sulfur bacteria isolated from the trophic lake Averno (Naples, Italy)

• Published in: International journal of hydrogen energy 2010-11, Vol.35 (22), p.12216-12223
• Main Authors: Bianchi, Lucia, Mannelli, Francesca, Viti, Carlo, Adessi, Alessandra, De Philippis, Roberto
• Format: Article
• Language: English
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Energy; Exact sciences and technology; Fuels; Hydrogen; Hydrogen production; Photofermentation; Poly-β-hydroxybutyrate; Purple non-sulfur bacteria; Rhodopseudomonas palustris; Trophic lake; Vegetable residues
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2010.08.038

Seventeen purple non-sulfur bacterial strains, isolated from the trophic lake Averno, Naples, Italy, were phylogenetically classified and their H 2-producing performances were tested utilizing various synthetic substrates and the fermentation broth derived from the spontaneous fermentation of vegetable residues. All the strains showed the capability to produce hydrogen on at least one of the four carbon substrates tested (malic, lactic, acetic and succinic acid). On lactate, Rhodopseudomonas palustris strain AV33 showed the best maximum production rate (50.7 ± 2.6 mL (H 2) L −1 h −1), with a mean rate, calculated on the whole period of production, of 17.9 mL ± 0.7 (H 2) L −1 h −1. In the presence of acetate, AV33 produced only few mL of H 2, but intracellularly accumulated poly-β-hydroxybutyrate up to a concentration of 21.4 ± 3.4% (w/w) of cell dry weight. Rp. palustris AV33 also produced H 2 on the fermentation broth supplemented with Fe, with a maximum production rate of 16.4 ± 2.3 mL (H 2) L −1 h −1 and a conversion yield of 44.2%. ► 17 purple non-sulfur H2-producing bacterial strains were isolated from a trophic lake. ► Rp.palustris AV33 showed a maximum production rate of 50.7 ± 2.6 mL (H 2) L −1 h −1. ► Rp.palustris AV33 intracellularly accumulated PHB up to 21.4 ± 3.4% (w/w). ► Rp.palustris AV33 produced H 2 using a low cost fermentation broth with a max rate of 16.4 ± 2.3 mL (H 2) L −1 h −1.