Chitosan-coated oleaginous microalgae-fungal pellets for improved bioremediation of non-sterile secondary effluent and application in carbon dioxide sequestration in bubble column photobioreactors. (March 2023)

• Record Type: Journal Article
• Authors: Maneechote, Wageeporn; Cheirsilp, Benjamas; Angelidaki, Irini; Suyotha, Wasana; Boonsawang, Piyarat
• Is Part Of: Bioresource technology. Volume 372(2023)
• Publication Date: 2023-03
• Subjects: Bioremediation -- Fungal pellets -- Immobilization -- Microalgae -- Secondary effluent; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2023.128675
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Fungal pellets immobilized microalgae cells efficiently and environmentally friendly. Microalgae–fungal (MF) pellets removed pollutants better than their mono-culture. MF pellets coated with chitosan enhanced both cell retention and dual bioremediation. Chitosan-coated MF pellets were also effective in CO2 removal from simulated flue gas. This system was also practical in 30 L bubble-column photobioreactors. Abstract: Oleaginous microalga Scenedesmus sp. SPP was rapidly immobilized in oleaginous fungal pellets by their opposite-surface-charges. Microalgae-fungal (MF) pellets were more effective in bioremediation of non-sterile secondary effluent than mono-culture. The optimal hydraulic retention time for dual bioremediation in semi-continuous mode was 72 h. The MF pellets coated with 0.4 %-chitosan improved removal efficiencies of COD, total nitrogen (TN), and total phosphorus (TP) up to 96.2±0.0 %, 88.2±2.8 % and 71.5±0.7 %, respectively, likely because of better cell retention and more nutrient adsorption and assimilation. Dual bioremediation by coated MF pellets was also successfully scaled up in 30-L bubble-column photobioreactors with improved COD, TN, and TP removal efficiencies of 98.5±0.0 %, 90.2±0.0 % and 79.5±2.1 %, respectively. This system also effectively removed CO2 from simulated flue gas at 71.2±0.4 % and produced biomass with high lipid content. These results highlight the effectiveness of bio-immobilization by fungal pellets; chitosan coating; and their practical applications in bioremediation and CO2 sequestration.