1097-0290/asset/cover.gif?v=1&s=169bf64713ffd27abfe496301dbedc7070f98e92 "Biotechnology and Bioengineering")
On leave from the Laboratory of Biotechnology and Physiology of Phototrophic Organisms, Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino (Moscow Region), 142290, Russia.
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Sustained hydrogen photoproduction by Chlamydomonas reinhardtii: Effects of culture parameters†
Article first published online: 3 MAY 2002
DOI: 10.1002/bit.10254
Copyright © 2002 Wiley Periodicals, Inc.
Additional Information
How to Cite
Kosourov, S., Tsygankov, A., Seibert, M. and Ghirardi, M. L. (2002), Sustained hydrogen photoproduction by Chlamydomonas reinhardtii: Effects of culture parameters. Biotechnol. Bioeng., 78: 731–740. doi: 10.1002/bit.10254
- †
This article is a U.S. Government work and, as such, is in the public domain in the United States of America
- ‡
On leave from the Laboratory of Biotechnology and Physiology of Phototrophic Organisms, Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino (Moscow Region), 142290, Russia.
- §
On leave from the Laboratory of Biotechnology and Physiology of Phototrophic Organisms, Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino (Moscow Region), 142290, Russia.
Publication History
- Issue published online: 3 MAY 2002
- Article first published online: 3 MAY 2002
- Manuscript Accepted: 3 JAN 2002
- Manuscript Received: 10 AUG 2001
Funded by
- U.S. Department of Energy H2 program. Grant Number: DE-AC36-99-GO10337
- Abstract
- References
- Cited By
Keywords:
- algae;
- hydrogen production;
- photobioreactor;
- sulfur deprivation;
- hydrogenase;
- oxygen sensitivity
Abstract
The green alga, Chlamydomonas reinhardtii, is capable of sustained H2 photoproduction when grown under sulfur-deprived conditions. This phenomenon is a result of the partial deactivation of photosynthetic O2-evolution activity in response to sulfur deprivation. At these reduced rates of water-oxidation, oxidative respiration under continuous illumination can establish an anaerobic environment in the culture. After 10–15 hours of anaerobiosis, sulfur-deprived algal cells induce a reversible hydrogenase and start to evolve H2 gas in the light. Using a computer-monitored photobioreactor system, we investigated the behavior of sulfur-deprived algae and found that: (1) the cultures transition through five consecutive phases: an aerobic phase, an O2-consumption phase, an anaerobic phase, a H2-production phase and a termination phase; (2) synchronization of cell division during pre-growth with 14:10 h light:dark cycles leads to earlier establishment of anaerobiosis in the cultures and to earlier onset of the H2-production phase; (3) re-addition of small quantities of sulfate (12.5–50 μM MgSO4, final concentration) to either synchronized or unsynchronized cell suspensions results in an initial increase in culture density, a higher initial specific rate of H2 production, an increase in the length of the H2-production phase, and an increase in the total amount of H2 produced; and (4) increases in the culture optical density in the presence of 50 μM sulfate result in a decrease in the initial specific rates of H2 production and in an earlier start of the H2-production phase with unsynchronized cells. We suggest that the effects of sulfur re-addition on H2 production, up to an optimal concentration, are due to an increase in the residual water-oxidation activity of the algal cells. We also demonstrate that, in principle, cells synchronized by growth under light:dark cycles can be used in an outdoor H2-production system without loss of efficiency compared to cultures that up until now have been pre-grown under continuous light conditions. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 731–740, 2002.