Culturing and utilization of marine algae from the sea surrounding Iceland
The variability of floating algae is high, but in the sea in the northern hemisphere, diatoms and whip algae are most common. Floating algae have been cultivated in Japan since about 1960 and used to enrich the nutritional content of various foods and thus have a positive effect on the health of both humans and animals. The high levels of omega 3 (ω3) and ω6 fatty acids in cold seaweed also make them an interesting crop. The main goal of the project was to isolate algae from the sea off Iceland and grow them in a laboratory under different conditions. The breeding of 4 species of cold-water algae, Phaeodactylum tricornutum, Microcysitis sp., Chlorella sp. Has been successfully isolated and maintained. and Dunaliella salina. The fat content and percentage of ω3 fatty acids were highest in P. tricornutum, but the species all contained a relatively high percentage of ω3 fatty acids and were easy to grow, although their growth varied depending on the situation. The results indicate that the fat content and ratio of different fatty acids vary according to growth stages. The results also show that equidae eat Microcystis sp. and Chlorella sp. and therefore it may be interesting to use these species for the enrichment of aquatic animals used as live feed animals in aquaculture of sea larvae in aquaculture. The project has resulted in new projects where work continues on the types of algae that have been successfully grown in pure cultivation. The aim of these studies is, on the one hand, to further develop methods of cultivation with the aim of increasing the proportion of fat and processing fats from algae, and, on the other hand, experiments with the cultivation of the species in wastewater from fish farms. An experiment has also been started in the breeding of cod juveniles with the use of these species of algae in the enrichment of feed animals of larvae.
Phytoplankton is the autotrophic component of the plankton community. Phytoplankton has been cultured since 1960 in Japan for a variety of purposes, including foodstock for other aquacultured organisms and a nutritional supplement. The most abundant groups of microalgae around Iceland are the diatoms and dinoflagelleates. High omega 3 (ω 3) and ω6 fatty acid content in cold water marine algae make them interesting for culturing. The main goal of the project was to search expedient plankton suitable for culturing and investigate the effects of different culture conditions. Four species of cold ‐ water algae have been isolated in monocultures, Phaeodactylum tricornutum, Microcysitis sp., Chlorella sp. and Dunaliella salina. P. tricornutum was found to contain the highest fatty acid and content3 content but all species were relatively high in ω3 content and were easy to culture. The results indicate that the fatty acid composition differed with respect to growth stages. The results also indicate that rotifers grazed on Microcystis sp. and Chlorella sp., thereby making them interesting for enrichment of the live prey commonly used in marine aquaculture. The project has resulted in new projects with further studies on the isolated species and developing methods for increasing their fat content, processing methods for extraction of the fat content and culturing using waste water from aquaculture farms. Also, two of the algae species are presently being used for enrichment of the live prey of cod larvae in an ongoing project.