High value pigment production and carbon sequestration through wastewater grown Spirulina (Arthrospira) platensis: A green technology for wastewater utilization

• Published in: Waste Management Bulletin Vol. 1; no. 3; pp. 1 - 10
• Main Authors: Kumari, Pragati, Shukla, S.P., Rathi Bhuvaneswari, G., Kumar, Saurav, Xavier, Martin, Kumar, Maushmi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2023; Elsevier
• Subjects: Carbon capture; Natural colorant; Phycocyanin; Spirulina; Wastewater utilization; Phycocyanin; Spirulina; Natural colorant; Wastewater utilization; Carbon capture
• ISSN: 2949-7507; 2949-7507
• DOI: 10.1016/j.wmb.2023.06.003

[Display omitted] •Biomass yield of 2.764 ± 0.03 g/L of S. platensis obtained in amended aquaculture wastewater.•Yield of biomass in amended wastewater was only 0.89% lesser than synthetic medium.•Biomass composition of demonstrated a maximum cell productivity of 0.0734 ± 0.0050 g/L/day.•Rate of carbon sequestration was 0.0314 g/L/day in wastewater cultured Spirulina.•Downstream processing of wastewater grown biomass yielded 101.95 ± 1.49 mg/g DW of the natural colorant Phycocyanin. This report describes a protocol for utilization of aquaculture wastewater for biomass production, high value pigment recovery and carbon sequestration through a cyanobacterium Spirulina (Arthrospira) platensis through a green process. The dry weight (2.76 ± 0.03 g/L) was almost comparable with the control showing a negligible decrease of 0.89%. During the 6 to 8 days of the culture duration, the biomass composition of amended aquaculture wastewater demonstrated a maximum cell productivity (0.0734 ± 0.0050 g/L/day), carbon sequestration (0.0314 ± 0.0021 g/L/day) and CO2 sequestration (0.1151 ± 0.0078 g/L/day), showing a substantial 20% improvement compared to the control. The yield of a pharmaceutically important pigment phycocyanin was 101.95 ± 1.49 mg/g DW in the wastewater grown cultures showing a negligible decrease (0.83%) compared to the synthetic medium grown cultures. The reduction in the cost of the synthetic medium through utilization of aquaculture wastewaters after certain amendments is a novel approach for an environmentally friendly and cost-effective production of S. platensis. The quality of biomass and phycocyanin in amended wastewater grown cultures was not altered. This report provides baseline data about aquaculture wastewater utilization for cyanobacterial biomass production, carbon sequestration and recovery of a valuable pigment phycocyanin through a simple and low-cost downstream process.