Simultaneous chromium removal and lipid accumulation by microalgae under acidic and low temperature conditions for promising biodiesel production. (February 2023)

• Record Type: Journal Article
• Authors: Song, Xueting; Liu, Bing-Feng; Kong, Fanying; Song, Qingqing; Ren, Nan-Qi; Ren, Hong-Yu
• Is Part Of: Bioresource technology. Volume 370(2023)
• Publication Date: 2023-02
• Subjects: Microalgae -- Chromium removal -- Acidic pH -- Lipid production -- Low temperature; 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.2022.128515
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Effect of Cr 6+ on algal growth and lipid synthesis at pH 3.5 and 15 °C was studied. The highest lipid content of 61.03 % was obtained at 5 mg/L Cr 6+ . Cr 6+ removal efficiency reached 91 % when Cr 6+ concentration was 0.5 mg/L. GSH was increased to eliminate oxidative damage caused by multiple stresses. MUFAs accumulation increased and PUFAs accumulation decreased. Abstract: Microalgae have become the hotspot of recent researches as heavy metals (HMs) adsorbent and biodiesel production feedstock. In this study, the cell growth, lipid production and Cr 6+ removal of Parachlorella kessleri R-3 at pH 3.5 and 15 °C were investigated. It was found that low concentration of Cr 6+ (0.5 to 2 mg/L) promoted the algal growth, whereas Cr 6+ higher than 5 mg/L inhibited the growth of P. kessleri R-3. Biomass concentration (2.40 g/L) and lipid productivity (131.79 mg/L d −1 ) reached the highest at 2 mg/L Cr 6+, and lipid content (61.03 %) reached the highest at 5 mg/L Cr 6+ . The maximum Cr 6+ removal efficiency of 91 % was obtained at 0.5 mg/L Cr 6+ treatment. Furthermore, fatty acid composition analysis showed that strain R-3 had a high C16-18 content of 74.88–89.21 %. This study provides new insight into the treatment of HMs and lipid production in cold regions.