Spirulina maxima for Phenol Removal: Study on its Tolerance, Biodegradability and Phenol-Carbon Assimilability

Microalgae-based bioremediation processes pose dual abilities of simultaneous CO2 fixation through photosynthesis and degradative effect on environmental pollutants. This study intends to investigate the tolerance and biodegradation capability of Spirulina maxima for removal of phenol. An assimilation study of the phenol-carbon was also conducted to elucidate if the phenol removal was dominated by physical adsorption on cell walls or through metabolic activities. S. maxima cells were found to be capable of growing on phenol up to a concentration of 400 mg l(-1), and they had a highest specific growth rate at a phenol concentration of 50 mg l(-1). The results suggested that the removal of phenol (as high as 97.5 %) was mainly due to biodegradation processes rather than a bioadsorption process. Moreover, it was evident that nearly 30 % of the C-13-labeled phenol content was discovered in the cellular fraction, indicating that the C-13-phenol-carbon was indeed assimilated to biomass followed by mineralize the carbon to CO2.