1.3.1.71	0°C, after 24 h: completely stable in presence of NADPH or NADH, 42% remaining activity in presence of 10 mM GSH or 2-mercaptoethanol, 33% remaining activity without additives, after 48 h: 93% remianing activity in prsence of 25% glycerol, 37% with 10% glycerol, and 13% remaining activity without additives