Simultaneous metabolism of benzoate and photobiological hydrogen production by Lyngbya sp.

Cyanobacteria are an inexpensive and sustainable source of photobiological H-2 production due to their simple nutritional conditions. Combination of toxic contaminant degradation with H-2 production is a promising approach in wastewater treatment. This study demonstrated that Lyngbya sp., a filamentous cyanobacterium, can generate H-2 in the presence of benzoate which, is a central intermediate during the anaerobic degradation of many aromatic compounds. The highest H-2 production rate of 17.05 mu mol H-2/g Chla/h was obtained in the second cycle and 600 mg/L benzoate was depleted within 64 h in H-2 production test. The strain has shown a higher H-2-producing capacity, which was comparable to those of certain noted strains such as N-2-fixing filamentous Anabaena variabilis PK84 and non-N-2-fixing filamentous Microcystis PCC 7806. The co-metabolism of benzoate for H-2 production by Lyngbya sp. makes it an interesting model strain for clean energy production and hazardous pollutant removal. (C) 2016 Elsevier Ltd. All rights reserved.