Cell leakage minimization by immobilization modulation of Chlorella sorokiniana NCIM 5561 and phosphate removal from wastewater

2021 
Microalgal cell leakage from immobilized beads due to mass transfer limitation and inert support matrix pose major problem during its application in the wastewater treatment process. To overcome this, Ca2+-alginate immobilization with water (AWIM—Alginate in Water Immobilized Microalgal system) and Blue Green (BG)-11 media (ABIM—Alginate in BG-11 Immobilized Microalgal system) using Chlorella sorokiniana NCIM 5561 was employed to determine their efficacy. Upon comparison of microalgal growth in the beads, ABIM resulted in better kinetic properties such as biomass yield, specific growth rate and productivity as 933.12 mg L−1, 0.42 day−1 and 77.78 mg L−1 day−1, respectively, as compared to AWIM. Flow cytometry and SEM analysis revealed that ABIM could hold up more cell density as compared to AWIM due to the reduced pore size and growth nutrient localization in the bead matrix. A novel strategy of co-cultivation of yeast along with microalgal cells under immobilized condition was attempted for improved phosphate uptake from the simulated wastewater. The results indicated that the co-cultivation resulted in minimum residual phosphate concentration of 0.75 mg L−1 as compared to ABIM and AWIM with corresponding concentration of 1.02 and 1.71 mg L−1, respectively. However, the rate of uptake was found to be superior with ABIM (0.41 h−1) than co-cultivation (0.29 h−1) and AWIM (0.23 h−1) that correlates to overall removal efficiency of 94.54%, 80.64% and 67.07%, respectively.
    • Correction
    • Source
    • Cite
    • Save
    • Machine Reading By IdeaReader
    62
    References
    0
    Citations
    NaN
    KQI
    []