Biochemical response of indigenous microalgal consortia to variations in nitrogen concentration of treated effluent. (May 2019)

• Record Type: Journal Article
• Authors: Okazaki, Hironori; Takabe, Yugo; Masuda, Takanori; Hoshikawa, Yoshiko
• Is Part Of: Bioresource technology. Volume 280(2019)
• Page Start: 118
• Page End: 126
• Publication Date: 2019-05
• Subjects: Indigenous microalgal consortia -- Treated effluent -- Total lipid -- Nitrogen -- Light irradiation; 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.2019.02.014
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Long exposure to nitrogen exhaustion had minor effects on total lipid accumulation. Total lipids were reduced under light and darkness after nitrogen replenishment. Total lipid reduction lagged behind nitrogen replenishment under nitrogen depletion. Total lipids were primarily utilised upon replenishment under nitrogen exhaustion. Immediate crude protein accumulation was observed after nitrogen replenishment. Abstract: Cultivation conditions influence microalgal cellular components, such as lipid accumulation under nutrient depletion, high light irradiation and salinity stress. In this study, indigenous microalgal consortia were cultivated in batch mode using an actual treated effluent. The temporal response of cellular components to the variations in nitrogen concentration and influence of light irradiation on the response were investigated. Prolonged exposure of indigenous microalgal consortia to nitrogen exhaustion had minor effects on total lipid accumulation and enhancement of energy content. Nitrogen replenishment was followed by immediate crude protein accumulation for growth recovery. Total lipid reduction was observed under light and dark conditions after nitrogen replenishment. A one-day lag after nitrogen replenishment in the total lipid reduction was revealed under nitrogen depletion; meanwhile, under nitrogen exhaustion, lipids were utilised as the primary carbon and/or energy source after replenishment, as represented by the decrease from 10.8% to 9.04% within 6 h after the replenishment.