Manifestation of behavioural and physiological functions of Synechococcus Miami BG 043511 in a photobioreactor

• Published in: Marine biology Vol. 140; no. 3; pp. 455 - 463
• Main Authors: Borodin, V B, Rao, K K, Hall, DO
• Format: Journal Article
• Language: English
• Published: 01.03.2002
• Subjects: Marine; Synechococcus; USA, Hawaii
• ISSN: 0025-3162

Synechococcus Miami BG 043511, a unicellular marine cyanobacterium, offers possibilities for biotechnological purposes. It was tested for the first time in the present work as a component of specially designed biosolar system. The testing was carried out using a 4.35-1 helical tubular photobioreactor. The cell culture of this cyanobacterium was found to exhibit persistent cyclic oscillations in O sub(2) evolution and CO sub(2) consumption during the growth in the photobioreactor under N sub(2)fixing autotrophic conditions and continuous illumination. The cycles of these two activities during bubbling of the culture with air + 2% CO sub(2) lasted for 23.5 h and were of the same pattern and phase. The cycles consisted of two phases: a short (8.3 h) and a long (15.2 h) phase, with a minor and a major peak of gas exchange, respectively. Additionally, the culture exhibited transient increase in optical density at each major peak of O sub(2) evolution. The growth rate of the continuous culture (4 mu g chl a/ml) of the cyanobacterium, sparged with CO sub(2)-enriched air under light of 150 mu E/m super(2)/s, was 0.024/h. The culture in the photobioreactor produced an appreciable amount of H sub(2) under argon + 2% CO sub(2). However, it produced no H sub(2) under air + 2% CO sub(2). The activation of H sub(2) production in the cyanobacterium by CO sub(2)-enriched argon was accompanied by frequent oscillations in the optical density, essential elongation of the cycle of O sub(2) evolution and inhibition of the growth rate of the culture. H sub(2) and O sub(2) evolution changed with time in very similar oscillatory patterns, but inversely to each other. The results showed that Synechococcus Miami BG 043511 could be successfully cultivated in the helical tubular type of biosolar system. It is also clear that further efforts should be made to extend our knowledge of this cyanobacterium.