Cold preservation of concentrated Nannochloropsis oculata

• Published in: Aquaculture Science Vol. 51; no. 1; pp. 117 - 118
• Main Authors: Harada, K. (Hyogo-ken. Tajima Fisheries Research Inst., Kasumi (Japan)), Sugino, M
• Format: Journal Article
• Language: Japanese; English
• Published: Japanese Society for Aquaculture Science 2003
• Subjects: ALGAE; Cold preservation; COLD STORAGE; CONCENTRATING; CULTURE TECHNIQUES; Nannochloropsis oculata
• ISSN: 0371-4217; 2185-0194
• DOI: 10.11233/aquaculturesci1953.51.117

Concentrated Nannochloyopsis oculata (50-150×108 cells/ml) by filtration is generally used in facilities for seedling production. The methods of cold preservation for the mass of concentrated N. oculata with the ability to multiply are by generally keeping them in cold storage with aerating or stirring in the tank, or keeping them stationary. But these methods have some problems, that aerating or stirring in the cold storage require apparatus to do this, and keeping stationary can't preserve N. oculata with an ability to multiply over the long-term. In this study the effects of cold preservation (at 8°C, keeping stationary) on the subsequent growth ability after various periods of time (up to and in excess of 100 days) of two different concentrations of N. oculata were compared. The densities of the concentrated N.oculata used were 100-130×108 cells/ml and 900-1, 000×108 cells/ml. In this study the highly concentrated N. oculata samples (900-1, 000×108 cells/ml) retained the ability to multiply over the long-term more than the other samples. These results indicate that highly concentrated N. oculata can be preserved with an ability to multiply after preservation in cold conditions over the long-term (100+days), and that concentrating to a thicker solution with the removal of more moisture than now in use (50-150×108 cells/ml) is more effective.