SIMULTANEOUS PRODUCTION OF H-2 AND O-2 IN CLOSED VESSELS BY MARINE CYANOBACTERIUM ANABAENA SP TU37-1 UNDER HIGH-CELL-DENSITY CONDITIONS

A marine cyanobacterium, Anabaena sp. TU37-1, exhibited stable product ion of hydrogen and oxygen in closed vessels. About 8.4 and 4.3 mL (at atmospheric pressure) of hydrogen and oxygen accumulated, respectivel y, in flasks with 20 mL gas phase during 48 h incubation. Thus, concen tration of H-2 and O-2 became 26 and 13% of the gas phase, respectivel y. Duration of hydrogen production was prolonged by the periodic gas r eplacement in the reaction vessel. The conversion efficiencies of phot osynthetically active radiation (fluorescent light, 22 W/m(2)) to hydr ogen were 2.4 and 2.2% during the initial 12- and 24-h incubation peri ods, respectively. (C) 1995 John Wiley and Sons, Inc.