Optimization of growth operational conditions for CO2 biofixation by native Synechocystis sp.

✍ Scribed by Lorena Martínez; Vanesa Redondas; Ana-Isabel García; Antonio Morán

• Publisher: Wiley (John Wiley & Sons)
• Year: 2011
• Tongue: English
• Weight: 330 KB
• Volume: 86
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/jctb.2568

✦ Synopsis

BACKGROUND: A fundamental step in assessing the viability of a CO 2 biofixation system based on microalgae is to identify the maximum CO 2 biofixation yield that can be achieved for this microorganism when it is cultivated under optimum operational growth conditions. Response surface methodology was applied to determine optimum culture conditions for CO 2 biofixation by a recently isolated freshwater cyanobacterium Synechocystis sp. The strain was cultivated in a 1 L bubble column photobioreactor, in semicontinuous mode.

RESULTS: Statistical analysis showed that temperature (from 22 to 39 • C), pH (from 7.2 to 8.8) and light intensity (from 928 to 2272 µE m -2 s -1 ), in addition to some of their interactions, had a significant effect on CO 2 biofixation. An optimum CO 2 biofixation rate of 2.07 gCO 2 L -1 culture day -1 was found within the experimental region, at an average light intensity 686 µE m -2 s -1 , pH 7.2 and temperature 35.3 • C. CONCLUSIONS: Based on these results, it is concluded that Synechocystis sp. presents a good tolerance to both high temperature and light intensity, characteristics which facilitate its application in outdoor CO 2 biofixation systems.