Melatonin enhances lipid production in Monoraphidium sp. QLY-1 under nitrogen deficiency conditions via a multi-level mechanism

• Published in: Bioresource technology Vol. 259; pp. 46 - 53
• Main Authors: Zhao, Yongteng, Li, Dafei, Xu, Jun-Wei, Zhao, Peng, Li, Tao, Ma, Huixian, Yu, Xuya
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.07.2018
• Subjects: Antioxidant systems; Lipid; Melatonin; Microalgae; Nitrogen deficiency; Signalling molecules; Nitrogen deficiency; Melatonin; Microalgae; Signalling molecules; Lipid; Antioxidant systems
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2018.03.014

[Display omitted] •Exogenous MT increased lipid content by 1.22-fold in alga under nitrogen deficiency.•Influence of MT on alga biochemistry was investigated.•MT alleviated the oxidative damage caused by nitrogen deficiency.•MT upregulated the signal molecular production of gibberellin acid.•MT enhanced stress resistance of alga cells. In this study, melatonin (MT) promoted lipid accumulation in Monoraphidium sp. QLY-1 under nitrogen deficiency conditions. The lipid accumulation increased 1.22- and 1.36-fold compared with a nitrogen-starved medium and a normal BG-11 medium, respectively. The maximum lipid content was 51.38%. The reactive oxygen species (ROS) level in the presence of melatonin was lower than that in the control group, likely because of the high antioxidant activities. The application of melatonin upregulated the gibberellin acid (GA) production and rbcL and accD expression levels but downregulated the abscisic acid (ABA) content and pepc expression levels. These findings demonstrated that exogenous melatonin could further improve the lipid production in Monoraphidium sp. QLY-1 by regulating antioxidant systems, signalling molecules, and lipid biosynthesis-related gene expression under nitrogen deficiency conditions.