ISOLATION AND CHARACTERISTICS OF ACID-TOLERANT AND ALUMINUM-TOLERANT BACTERIUM

A screening was attempted to isolate microorganisms that tolerate high concentrations of H+ and ionic aluminum in acidic soils. A new microo rganism that can grow in the presence of a high concentration of Al3at low pc was isolated from acidic tea fields. The microorganism, desi gnated strain ST-3991, has been identified as a Flavobacterium sp. It can tolerate aluminum concentrations up to 2000 ppm at pH 3.5. The bac terial growth was affected by the concentration of ionic aluminum. Whe n the bacterium was incubated at an initial pH 3.3 in liquid medium co ntaining 100 ppm aluminum, the pc of the medium increased steeply with time, and the medium reached pH 4.4 after 10 days. The bacterium is c onsidered to be useful to improve acidified soils by decreasing the io nic aluminum concentration, while preserving indigenous terrestrial ec osystems.