MYCODEXTRAN (nigeran) is an unbranched polysaccharide composed of a regular alternating sequence of α–(1rarr;3) and α–(1→4) linked glucopyranosyl units. It is produced in the mycelia of various species of moulds1. Reese and Mandels have recently reported2 the isolation and partial purification of an inducible glucanase (mycodextranase) produced in the culture filtrates of selected species of fungi grown on a medium containing mycodextran as a carbon source. The enzyme is an endoglucanase that hydrolyses nigeran to produce hexameric and tetrameric units which are subsequently hydrolysed to produce the disaccharide nigerose (O–α–D–glucopyranosyl–(1→3)–D–glucose) as the final product2.