해양심층수기반 배지를 이용한 Spirulina platensis 성장과 경제성 분석

Abstract

Abstract

The growth and economic analysis of Spirulina platensis using medium based on deep sea water

Lim, Dae Hack Advisor : Prof. Park, Cheon-Young Dept. of Energy & Resource Engineering Graduate School, Chosun University

Deep sea water is psychrophilic and clean and has abundant marine resources containing significant nutrients as calcium and magnesium due to low temperature and density. Thanks to these advantages, deep sea water has been commercialized in various fields such as development of marine products and healthy food. However, among these advantages, deep sea water significantly retaining inorganic nutrients was successfully used to cultivate microalgae, the technical development of a culture system is insignificant. In particular, economical efficiency of deep sea water-based preparation media is insignificant and technical skills to secure optimal growth characteristics of deep sea water-based microalgae have not been fully developed. Accordingly, this study is to prepare a SP medium and a low-cost medium using deep sea water and cultivate S. platensis using these media. Based on the results of the growth experiment of the microalgae, this study is to investigate the maximum specific growth rate, doubling time, yield and economical efficiency according to production. When the SP medium was mixed with deep sea water in diverse compositions to grow S. platensis, its maximum growth rate was found in the mixing ratio of 50:50. In these conditions, its maximum specific growth rate was 0.094 1/day, its double time was 3.058 day, and the yields of N, P K was 0.160, 0.081, and 0.131, respectively. When the low cost medium was mixed with deep sea water in diverse compositions to grow S. platensis, its maximum growth rate was found in the mixing ratio of 75:25. In these conditions, its maximum specific growth rate was 0.099 1/day, its double time was 3.007 day, and the yields of N, P K were 0.170, 0.029, and 0.033, respectively. This study mixed the SP medium with the low cost medium in diverse mixing proportions to grow S. platensis. When deep sea water was mixed with the Sp-medium at the ratio of 50:50(W/W), the maximum dry cell weight obtained was 1.16 g/L and its production cost was 142.62 KRW/g. When deep sea water was mixed with the low cost medium at the ratio of 25:75, the maximum dry cell weight was 0.88 g/L and the production cost was 8.17 KRW/g. When deep sea water-based low cost medium was used to grow S. platensis, the economical efficiency was significant because of low production cost. It is judged that the low-cost medium and the SP medium were very eco-friendly as clean deep sea water was used to grow S. platensis. Therefore, it is suggested that further studies on pre-treatment technology of deep sea water and hazard evaluation of S. platensis grown in media with diverse mixing proportions are needed.