*********** 031293B.BIO *********** Country: Japan From: JETRO February 1993 v. 20, no. 11 p. 15 & 41 In two parts: Part I: 93-02-100-06 DOCOSAHEXAENOIC ACID PRODUCTION BY MARINE MICROALGAE Prof. T. Matsunaga and his research team at the Faculty of Technology, Tokyo University of Agriculture and Technology, have succeeded in producing docosahexaenoic acid (DHA), an antihypertensive and memory-enhancing drug, by the culture of a marine microalga. DHA is an unsaturated fatty acid, and has 22 carbon atoms with 6 double carbon-to-carbon bonds. Previously, reports have announced that DHA is carcinostatic, antihypertensive, and antiallergic. In experiments, mice dosed with DHA grew in Teaming ability. Some researchers say the drug makes man more intelligent. Admittedly, DHA is found in human brains, although it cannot be synthesized in the human body. DHA is concentrated in fatty tissue at the back of fish eyes, from which DHA is separated and marketed as a supplementary food for health maintenance and enhancement. This DHA commodity is of course deodorized, but often smells fishy. The general challenge to research is to explore the production of materials by marine microalgae. The research team conducted screening of microalgae to find a microalga producing DHA. A bioreactor was built with a lens collecting sunshine and sending it through dispersive glass fibers into the incubator. The culture solution was made of sea water, and the microalga cultured in the reactor was Isochrysis galbana, a species of the Haptophyceae. After 6-day culture, the algae were taken out and freeze- dried, weighed and analyzed. The analysis revealed that the dried cells contain 14 wt% fatty acid, and DHA accounts for 16 wt% of the fatty acid. This means that the dried cells have 2 wt% DHA. Compared with fish fatty acid, which contains 20 wt% DHA, the production of DHA by microalgae seems realistic. The research team has determined the influence of light irradiation on the growth rate of L galbana and DHA production. The experiments showed that some Haptophyceae growing under optimum incubating conditions have a DHA content increasing when subjected to either dark condition treatment or low temperature treatment. Tokyo University of Agriculture and Technology Faculty of Technology 2-24-16, Naka-machi, Koganei City, Tokyo Tel: +81-423-81-4221 Fax: +81-423-85-7713 ++++++ End Part I ++++++ Part II 93-02-008-03 C02 FIXATION TECHNOLOGY USING BIOSOLAR REACTOR SYSTEM Prof. T. Matsunaga of Tokyo University of Agriculture and Technology, together with Tokyo Gakugei University, Onoda Cement Co., Ltd. and La Foret Engineering Co., Ltd., has jointly cultured calcareous algae with a bioreactor using a solar light collector and optical fiber, to fix carbon dioxide (CO2) and form superfine particles (coccolith) of calcium carbonate. C02 fixation is possible through simultaneous photosynthesis and carbonization, so this research project paves the way for the fixation Of C02 that is the cause of global warming. Artificial satellites recently showed that large quantities of calcareous algae proliferate in certain sea regions, which is vital data corroborating that this may be the result Of C02 fixation. The research team is also engaged in research to use coccolith particles separated from calcareous algae, and has shown the possibility of recycling these particles. In the experiments which were conducted, the solar light condensed with a solar light collector was transmitted with optical fibers to calcareous algae in a bioreactor, and the production of coccolith from a culture solution (2.2 liters) was attempted. When the solar light was irradiated for 8 days, 43 mg/ liter of coccolith were generated, of which two-thirds produced biomass and one-third produced calcareous algae, indicating that C02 fixation occurs satisfactorily. The capacity for producing calcium carbonate increased when the solar light was irradiated more intensively. In the stage of photosynthesis and carbonization, the pH value increased beyond 7 (alkalinization), which corroborates that C02 fixation is done completely. The research team, having shown C02 fixation with calcareous algae, plans to install a large continuous facility in 1993 with the objective of establishing a system for the mass forming of coccolith and for developing large-scale C02 fixation technology. Tokyo University of Agriculture and Technology Faculty of Technology 2-24-16, Naka-machi, Koganei City, Tokyo 184 Tel: +81-423-81-4221 Fax: +81-423-84-3804 ************** END Msg. B.BIO **************