PURPOSE: To obtain micro-algae containing much polysaccharides in the solid substance of the algal bodies at a high cell concentration.
CONSTITUTION: An alga Porphyridium.cruentum is planted in seawater (culture medium) containing 0.035M sodium nitrate and 0.0005M potassium dihydrogenphosphate at 5×106 cells/ml concentration and cultured. On the 7th day after starting the culture, the number of algal cells attains 6.2×107 cells/ml. The resultant culture solution is then subjected to solid-liquid separation. Algae are subsequently planted in the obtained precipitates in the same manner as that in the aforementioned culture medium, except that the sodium nitrate concentration is regulated to 0.0035M. Micro-algae are obtained at 13.1×107 cells/ml (12.5g/l polysaccharide concentration) 20 days after starting the culture. The polysaccharides can efficiently be extracted from the micro- algae obtained by the method of this invention.
MINAMISAKO KAZUE
NAKATANI TATSUO
