Journal of Fundamentals of Renewable Energy and Applications
Open Access

Hydrogen production by cyanobacteria Anabaena sp. (1448) in nitrogen-deprived cultures under different light intensities

International Congress and Expo on Biofuels & Bioenergy

August 25- 27, 2015 Valencia, Spain

Sarah Regina Vargas, Paulo Vagner dos Santos, Marcelo Zaiat and Maria do Carmo Calijuri

Posters-Accepted Abstracts: J Fundam Renewable Energy Appl

Abstract :

An efficient way to produce hydrogen is biologically through microorganisms cultures, which can have a production as
efficient as physical and chemical processes. This research aimed to investigate biological hydrogen production with the
cyanobacteria Anabaena sp. (1448 - UTEX) by indirect biophotolysis (via nitrogenase) in batch cultures. The experiments were
carried out in triplicate using Duran glass bottles as photobioreactors (500 mL). Anabaena sp. was cultivated axenic in BG-11
medium and pH 9.2 in two phases: in the first stage, cultures were maintained in aerobic conditions with nitrogen limitation
(10 mg.L-1) to stimulate heterocyst formation, until the middle of the exponential phase; in the second stage, the biomass
produced was centrifuged (2000 rpm for 10 minutes), washed (2x) and transferred to closed photobioreactors which had their
atmosphere exchanged for argon and were maintained for 204 hours under nitrogen deprivation and two lights intensities
(60 and 200 μE.m-2.s-1) for hydrogen production studies. Gas chromatography and Gompertz model were used to measure
hydrogen production and hydrogen production rate, respectively. The hydrogen productivity was 44.9±1.14 μmol.L-1.h-1 at the
200 μE.m-2.s-1 light and reached the yield of 8.7±0.73 mmol.L-1. At the light of 60 μE.m-2.s-1 productivity was 43.5±1.39 μmol.L-
1.h-1 and reached the yield of 8.7±0.72 mmol.L-1. Although the productivity and yields did not change between lights tested,
the experiment showed that the Anabaena strain is able to produce hydrogen biologically at rates close to or even better than
other microbial cultures.

Biography :

Sarah Regina Vargas is a Biologist and an MSc graduate in Science from University of São Paulo, São Carlos, Brazil. She has experience with microbiology and
ecotoxicology. She is currently a PhD candidate in Science at Hydraulics and Sanitation Department, University of São Paulo and her research is focused on the
hydrogen production with microalgae and cyanobacteria.