A new fructosyltransferase produced by a new isolate of Bacillus macerans EG-6 showed mainly hydrolyzing activity at 10 g sucrose/l, while both hydrolyzing and transfructosylating activity were observed at 100 g sucrose/l. In contrast, the new enzyme catalyzed an almost exclusively fructosyl transfer reaction with 500 g sucrose/l, producing selectively 42% of fructooligosaccharide (GF(4)) without forming other fructooligosaccharides. The reaction was optimal at pH 6.0 and 37 degrees C.