Development of an automatic system for cultivating the bioluminescent
heterotrophic dinoflagellate <i>Noctiluca scintillans</i> on a
100-liter scale

You, Ji Hyun; Jeong, Hae Jin; Park, Sang Ah; Ok, Jin Hee; Kang, Hee Chang; Eom, Se Hee; Lim, An Suk; You, Ji Hyun; Jeong, Hae Jin; Park, Sang Ah; Ok, Jin Hee; Kang, Hee Chang; Eom, Se Hee; Lim, An Suk

doi:2022.37.2.149

Algae > Volume 37(2); 2022 > Article

Research Article

Algae 2022;37(2): 149-161. doi: https://doi.org/10.4490/algae.2022.37.6.8

Development of an automatic system for cultivating the bioluminescent heterotrophic dinoflagellate Noctiluca scintillans on a 100-liter scale

Ji Hyun You¹, Hae Jin Jeong^1,2,*, Sang Ah Park¹, Jin Hee Ok¹, Hee Chang Kang¹, Se Hee Eom¹, An Suk Lim³

¹School of Earth and Environmental Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Korea
²Research Institute of Oceanography, Seoul National University, Seoul 08826, Korea
³Division of Life Science & Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 52828, Korea

*Corresponding Author

Hae Jin Jeong, Tel: +82-2-880-6746, Fax: +82-2-874-9695,
Email: hjjeong@snu.ac.kr

Received: April 19, 2022; Accepted: June 8, 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

Noctiluca scintillans is a heterotrophic dinoflagellate that causes red-colored oceans during the day (red tides) and glowing oceans at night (bioluminescence). This species feeds on diverse prey, including phytoplankton, heterotrophic protists, and eggs of metazoans. Thus, many scientists have conducted studies on the ecophysiology of this species. It is easy to cultivate N. scintillans at a scale of <1 L, but it is difficult to cultivate them at a scale of >100 L because N. scintillans cells usually stay near the surface, while prey cells stay below the surface in large water tanks. To obtain mass-cultured N. scintillans cells, we developed an automatic system for cultivating N. scintillans on a scale of 100 L. The system consisted of four tanks containing fresh nutrients, the chlorophyte Dunaliella salina as prey, N. scintillans for growth, and N. scintillans for storage, respectively. The light intensities supporting the high growth rates of D. salina and N. scintillans were 300 and 20 μmol photons m^-2 s^-1, respectively. Twenty liters of D. salina culture from the prey culture tank were transferred to the predator culture tank, and subsequently 20 L of nutrients from the nutrient tank were transferred to the prey culture tank every 2 d. When the volume of N. scintillans in the predator culture tank reached 90 L 6 d later, 70 L of the culture were transferred to the predator storage tank. To prevent N. scintillans cells from being separated from D. salina cells in the predator culture tank, the culture was mixed using an air pump, a sparger, and a stirrer. The highest abundance of N. scintillans in the predator culture tank was 45 cells mL^-1, which was more than twice the highest abundance when this dinoflagellate was cultivated manually. This automatic system supplies 100 L of N. scintillans pure culture with a high density every 10 d for diverse experiments on N. scintillans.

Key words: bioluminescence; feeding; food web; mass culture; protist; red tide