Propagation of Algae Mixotrophically Using Glucose as Substrate For Biomass Production

Abstract 

Algae are large and diverse group of microorganisms that can carry out photosynthesis since they are able to capture energy from sun light. Algae may range in size from single cells as small as one micrometer to large seaweeds that grow to over 50 meters. Algae grow in the wide and are prompt to attack by predators and can easily be invaded which could result to competition that will eventually lead to low production of biomass which are important to organisms and the ecosystem. Chlorella viriabilis recently renamed Chlorella viriabilisNC64A that is a bona fide member of the true Chlorella genus, belonging to the Trebouxiophyceae was used in this present research. Chlorellaviriabilis was propagated in BG11 media enriched with 0.5g/L of glucose for mixotrophic growth and in autotrophic growth condition. The cell culture was monitored using the hemocytometer for increase in cells concentration. At the end of three weeks, the cells were harvested after centrifugation and dried in the oven. The mixotrophic dried biomass weighed 0.5g/L and that of the autotrophic weighed 0.1g/L. The results for protein analyses for both mixotrophic and autotrophic yielded 1.118g/L &0.07g/L respectively. Also, the results for the glucose was obtained using the Mercz protocol, the mixotrophic had higher glucose content than the autotrophic with 0.0564g/L & 0.0266g/L respectively. The cell concentration was more in the autotrophic than in mixotrophic but the mixotrophic cell culture had bigger cell size which showed the presence of accumulated materials. Glucose enhanced the production of algal biomass