Glucose oxidase (GOD) was illuminated with white linearly polarized light (WLPL). The enzyme was illuminated at room temperature in separate vessels then admixed to a reactor filled with D-glucose. The illumination of the enzyme for 60 min at 25-30 degrees C and pH 6.5-7.0 provided its superior stimulation as proven in the oxidation of beta-D-glucose. Lyophilization of the illuminated enzyme reduced its activity by, approximately, 30%. (C) 2009 American Institute of Chemical Engineers Biotechnol. Prog., 26: 393-396, 2010