Proceedings of the 1986 International Congress on Renewable Energy Sources. Growth and photoproduction of H2 by Rhodoseudonomas palustris under light-dark cycles. International Congress on Renewable Energy Sources [18-23 Mayo 1986, Madrid].

Consejo Superior de Investigaciones Científicas.
Terol, S., ed. Vincenzini, M. ... [et al.].

1987

V.1
1113
CIENA

84-00-6673-1

The ability of Rhodopseudomonas palustris to grow and at the same time to evolve hydrogen in the presence of a suitable nitrogen source was essayed. Under continuous light, in the laboratory, biomass and hydrogen yields were respectively 1230 mg (dry weight) and 540 ml per liter of culture. Light-dark cycles had a stimulating effect on the growth and on the activity of the uptake hydrogenase which in the dark periods was able to recycle all the hydrogen produced in the light. Hydrogen uptake occurred also in continuosly illuminated cultures but only when the N-source was exhausted. The H2-recycling was active when the organic substrate (DL-malate) was still present and resulted not dependent on oxygen availability. Moreover it seems to be correlated to the biosynthesis of non-nitrogenous storage compound, i.e. poly-B-hydroxybutyrate. Taking into account the results obtained in the laboratory, outdoor experiments, under natural conditions of light and temperature, were carried out. In order to avoid, H2-uptake in the dark, hydrogen produced in the light was continuosly removed. The culture was performed in a 22 1 photobioreactor on synthetic medium containing Na-glutamate ans Na-malate as nitrogen and carbon sources. In a typical experiment, after 7 days of culture, 16 g of R.palustris cell (dry weight) and 9 1 of gas were obtained. The h2 produced accounted for c.a. 25. ABSTRACT. of the energy content of the biomass. The process looks promising in the reclamation of waste water having a low nitrogen content. INTRODUCTION. MATERIALS AND METHODS. RESULTS AND DISCUSSION. REFERENCES.

Presenta ilus. y gráfs.

GENERAL; ENERGIA DEL HIDROGENO; NITROGENO; FOTOPRODUCCION; BACTERIAS; EXPERIMENTOS;