Evaluation of photosynthetic efficacy and CO2 removal of microalgae grown in an enriched bicarbonate medium

Abstract

Bicarbonate species in the aqueous phase is the primary source for CO2 for the growth of microalgae. The potential of carbon dioxide (CO2) fixation by Chlorella pyrenoidosa in enriched bicarbonate medium was evaluated. In the present study, effects of parameters such as pH, sodium bicarbonate concentration and inoculum size were assessed for the removal of CO2 by C. pyrenoidosa under mixotrophic condition. Central composite design tool from response surface methodology was used to validate statistical methods in order to study the influence of these parameters. The obtained results reveal that the maximum removal of CO2 was attained at pH 8 with sodium bicarbonate concentration of 3.33 g/l, and inoculum size of 30 %. The experimental results were statistically significant with R 2 value of 0.9527 and 0.960 for CO2 removal and accumulation of chlorophyll content, respectively. Among the various interactions, interactive effects between the parameters pH and inoculum size was statistically significant (P < 0.05) for CO2 removal and chlorophyll accumulation. Based on the studies, the application of C. pyrenoidosa as a potential source for carbon dioxide removal at alkaline pH from bicarbonate source is highlighted.

Special issue in honour of Prof. Reto J. Strasser - Photosynthesis response of microalgae (Tetradesmus wisconsinensis) to different inorganic carbon sources probed with chlorophyll fluorescence analysis

“…Therefore, our result suggests that bicarbonate and CO2 can be used alternatively with similar effect on biomass growth of algae. In some studies, bicarbonates as an inorganic carbon source gave higher biomass and lipid production (Abinandan andShanthakumar 2016, Mokashi et al 2016).…”

Optimization of nutrient stress using C. pyrenoidosa for lipid and biodiesel production in integration with remediation in dairy industry wastewater using response surface methodology

“…It should be noted though that the optimal range of nutrients (NO 3 − and PO 4 −3 ) lies outside the range of experiment values. The lack of fit test with p value of 0.05 showed that the model is satisfactorily fitted with the experimental design data (Abinandan and Shanthakumar 2016).…”

Opportunities for phycoremediation approach in tannery effluent: A treatment perspective

“…To overcome the mass transfer limitation and acidification of CO 2(g) , the carbonates produced from CO 2(g) can be used as an alternative inorganic carbon source . Several studies have been conducted using bicarbonate as a carbon source for the growth of microalgae . The microalgae potential of CO 2 fixation by Chlorella pyrenoidosa in bicarbonate enriched medium was reported with the maximum CO 2 removal of 86.32% and accumulation of 4.61 mg/L chlorophyll content at pH 8 with sodium bicarbonate concentration of 3.33 g/L .…”

“…Several studies have been conducted using bicarbonate as a carbon source for the growth of microalgae . The microalgae potential of CO 2 fixation by Chlorella pyrenoidosa in bicarbonate enriched medium was reported with the maximum CO 2 removal of 86.32% and accumulation of 4.61 mg/L chlorophyll content at pH 8 with sodium bicarbonate concentration of 3.33 g/L . The chlorophyll content of microalgae Chlorella vulgaris cultivated in NaHCO 3 (1.125 g/L) supplemented wastewater was increased up to 9.6 mg/L and the nutrient (Nitrate) removal efficiency was 13.5% better compared with 2% CO 2(g) as a carbon source .…”