| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject new bacterium tolerant to a salt solution having a concentration similar to or higher than sea water, capable of growing even in the presence of a substrate in high concentration, of a marine microorganism belonging to the family Nitrosomonas and useful for waste water treatment, etc., through a nitration-denitrification reaction caused by the organism. SOLUTION: This Nitrosomonas sp. MA-6 strain (FERM BP-4966) tolerant to a salt solution having a concentration similar to or higher than sea water and capable of growing even in the presence of a substrate in high concentration is a new salt-tolerant ammonia-oxidizing marine bacterium belonging to the family Nitrosomonas. The bacterium is useful for the treatment of a waste water having a high salt concentration through a nitration-denitrification reaction caused by the organism, and obtained by the following processes: porous ceramic beads as adhesive carriers of microorganisms are collected from a nitrification tank of a cultivation apparatus for a marine fish; the beads are placed into test tubes containing the sea water collected at Jougashima Island in Kanagawa prefecture; the test tubes are vigorously stirred to release and suspend the microorganisms adhered on the surfaces of the carriers into the sea water; the suspension of the microorganisms is cultured after the addition of a medium containing a muation inducing agent; and a variant having high ammonium oxidizing function is selected from the cultured mixture through a screening process. |
