EICOSAPENTAENOIC ACID-RICH BIOMASS PRODUCTION BY THE MICROALGA PHAEODACTYLUM-TRICORNUTUM IN A CONTINUOUS-FLOW REACTOR

The marine diatom Phaeodactylum tricornutum Bohlin is a potential sour ce of the pharmaceutically valuable omega 3 polyunsaturated fatty acid eicosapentaenoic acid (EPA). The results of indoor continous growth o f Phaeodactylum tricornutum Bohlin ar reported. The relationships betw een dilution rate (D), nitrate concentration and chemical composition were studied. Higher biomass and lipid productivities were obtained at low D values. EPA was found to be an intermediate metabolite and the best productivity (6 mg l(-1) day(-1)) was achieved for D values rangi ng from 0.32 to 0.50 day(-1). Under optimum conditions, 84 and 11%, re spectively, of total recovered EPA were present in monogalactosyldiacy lglycerol (MGDG) and in triacylglycerol (TG) moieties, respectively. R ecorded EPA/AA and EPA/20.4 omega 3 ratios for all tested dilution rat es were among the highest values ever reported, showing EPA purificati on to be easier to perform from this starting material than from many others commonly in use. (C) 1996 Elsevier Science Ltd.