Production enhancement of red cyst Haematococcus cells

Abstract

Haematococcus sp. are commercial photosynthetic green microalga, and it accumulates secondary metabolic products such as high value-added astaxanthin. Generally, Haematococcus is reported low growth rates and cell density when the cells are cultured with traditional culture media. Despite the astaxanthin is important for human health, the culture cost (nutrients, water, land and system etc.) are quite high yet. Thus affordable culture condition plays an important role in the mass production and sustainability of the strain. The purpose of this study was to develop for reducing culture cost by invented culture method and to investigate an optimal condition for biomass production of the Haematococcus sp. KORDI03 (KCTC 12348BP). The broth-cultured strain (3.2 x 106 cells/mL, 0.0012 g/L) was inoculated by different conditions of inoculation volume and spray feed interval on BBM medium-based plates (Ø90 x 25 x duplicate) under waterless culture plate with room temperature (28 ± 0.5°C) and fluorescence light (12: 12 L: D cycle) conditions during a month. In the results, red cyst cells were observed from 10 days after inoculation (over 50% confluence), and the final biomass of dried red cyst cells were recorded peak of 4.47 ± 0.18 g/L in the condition of 1 mL inoculation vol. and 1 day-fed interval. The astaxanthin content in the dry biomass varied between 0.1-1.1% (w/w). The culture methodology in this study has a convenient process and affordable for the production of red cyst cells from Haematococus biomass.