Statistical optimization of phytol and polyunsaturated fatty acid
production in the Antarctic microalga <i>Micractinium variabile</i>
KSF0031

Kim, Eun Jae; Chae, Hyunsik; Koo, Man Hyung; Yu, Jihyeon; Kim, Hyunjoong; Cho, Sung Mi; Hong, Kwang Won; Lee, Joo Young; Youn, Ui Joung; Kim, Sanghee; Choi, Han-Gu; Han, Se Jong; Kim, Eun Jae; Chae, Hyunsik; Koo, Man Hyung; Yu, Jihyeon; Kim, Hyunjoong; Cho, Sung Mi; Hong, Kwang Won; Lee, Joo Young; Youn, Ui Joung; Kim, Sanghee; Choi, Han-Gu; Han, Se Jong

doi:2022.37.2.175

Algae > Volume 37(2); 2022 > Article

Research Article

Algae 2022;37(2): 175-183. doi: https://doi.org/10.4490/algae.2022.37.4.1

Statistical optimization of phytol and polyunsaturated fatty acid production in the Antarctic microalga Micractinium variabile KSF0031

Eun Jae Kim¹, Hyunsik Chae¹, Man Hyung Koo², Jihyeon Yu¹, Hyunjoong Kim^1,3, Sung Mi Cho^1,4, Kwang Won Hong⁵, Joo Young Lee⁴, Ui Joung Youn^1,5, Sanghee Kim¹, Han-Gu Choi¹, Se Jong Han^1,5,*

¹Division of Life Sciences, Korea Polar Research Institute, Incheon 21990, Korea
²Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Korea
³Department of Systems Biology, Institute of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
⁴Department of Polar Sciences, University of Science and Technology, Incheon 21990, Korea
⁵R&D Department, Microalgae Ask Us Co., Ltd., Gangneung 25451, Korea

*Corresponding Author

Se Jong Han, Tel: +82-32-760-5521, Fax: +82-32-760-5509,
Email: hansj@kopri.re.kr

Received: October 20, 2022; Accepted: April 1, 2022. Published online: June 21, 2022.

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

ABSTRACT

Polar microorganisms produce physiologically active substances to adapt to harsh environments, and these substances can be used as biomedical compounds. The green microalga Micractinium variabile KSF0031, which was isolated from Antarctica, produced phytol, a natural antimicrobial agent. Furthermore, several polyunsaturated fatty acids (PUFAs), including omega-3, exhibit antioxidant properties. Here statistical methods (Plackett-Burman design and Box- Behnken design) were used to optimize the culture medium of KSF0031 to improve biomass production, and K₂HPO₄, MgSO₄·7H₂O, and ammonium ferric citrate green (AFCg) were selected as significant components of the culture medium. Changes in the concentration of K₂HPO₄ and MgSO₄·7H₂O as positive factors and AFCg as a negative factor affected cell growth to a remarkable degree. The biomass production in a 100 L culture using the optimized medium for 24 d at 18°C was improved by 37.5% compared to that obtained using the original BG-11 medium. The quantities of PUFAs and phytol obtained were 13 mg g^-1 dry cell weight (DCW) and 10.98 mg g^-1 DCW, which represent improved yields of 11.70% and 48.78%, respectively. The results of this study could contribute to an improved production of phytol and fatty acids from Antarctic microalgae in the biomedical industry.

Key words: Antarctic algae; growth medium optimization; Micractinium variabile; phytol; polyunsaturated fatty acids