Enhancement of the lipid productivity and fatty acid methyl ester profile of Chlorella vulgaris by two rounds of mutagenesis

Ehsan Sarayloo; Salim Simsek; Yigit Sabri Unlu; Gul Cevahir; Can Erkey; Ibrahim Halil Kavakli

doi:10.1016/j.biortech.2017.11.105

Enhancement of the lipid productivity and fatty acid methyl ester profile of Chlorella vulgaris by two rounds of mutagenesis

Bioresour Technol. 2018 Feb:250:764-769. doi: 10.1016/j.biortech.2017.11.105. Epub 2017 Dec 2.

Authors

Ehsan Sarayloo¹, Salim Simsek², Yigit Sabri Unlu³, Gul Cevahir³, Can Erkey¹, Ibrahim Halil Kavakli⁴

Affiliations

¹ Department of Chemical and Biological Engineering, Koc University, Rumelifeneri Yolu, Sariyer, Istanbul, Turkey; TUPRAS Energy Research Center, Koc University, Rumelifeneri Yolu, Sariyer, Istanbul, Turkey.
² Department of Chemical and Biological Engineering, Koc University, Rumelifeneri Yolu, Sariyer, Istanbul, Turkey.
³ Department of Biology, Istanbul University, 34134 Suleymaniye, Istanbul, Turkey.
⁴ Department of Chemical and Biological Engineering, Koc University, Rumelifeneri Yolu, Sariyer, Istanbul, Turkey; Department of Molecular Biology and Genetics, Koc University, Rumelifeneri Yolu, Sariyer, Istanbul, Turkey; TUPRAS Energy Research Center, Koc University, Rumelifeneri Yolu, Sariyer, Istanbul, Turkey. Electronic address: hkavakli@ku.edu.tr.

PMID: 29227826
DOI: 10.1016/j.biortech.2017.11.105

Abstract

In this study, we applied a second round of random mutagenesis using ethyl methanesulfonate to further increase the lipid productivity of a Chlorella vulgaris mutant strain. We generated a mutant (UV715-EMS25) with a lipid content and biomass that were respectively 67% and 35% higher than those of the wild type (WT). The highest achieved lipid productivity in UV715-EMS25 was 91 mg L^-1 day^-1. Gas chromatography-mass spectrophotometric analysis revealed that the fatty acid methyl ester content of the mutant was 3.9-fold higher compared with that of WT cells. Amounts of saturated and monounsaturated fatty acids were also higher in the mutant, while the total amounts of polyunsaturated fatty acids were lower. Finally, the mutant displayed superior lipid productivity compared with the WT during pilot-scale cultivation in a flat panel photobioreactor. All these results demonstrate that UV715-EMS25 is highly suitable for biodiesel production.

Keywords: Biodiesel; Chlorella vulgaris; Ethyl methanesulfonate (EMS); Random chemical mutagenesis.

MeSH terms

Biofuels
Biomass
Chlorella
Chlorella vulgaris*
Fatty Acids*
Lipids
Mutagenesis

Substances

Biofuels
Fatty Acids
Lipids