TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Method: In (M1), the denaturing step is carried out at 10-50 degreesC, preferably at room temperature. The denaturing step provides the application to the substrate of gaseous ozone as denaturing unit, UV waves as denaturing unit for a predetermined time, or UV waves and gaseous ozone as combined denaturing unit. The combined denaturing unit is generated by a same device, that is both a source of UV waves and an ozone generator. The application to the substrate of UV waves and of gaseous ozone as denaturing unit is carried out in different times. The step of application to the substrate of UV waves is carried out at a predetermined frequency and intensity at which the UV waves produce ozone in the substrate. EXAMPLE - A 10% solution of saccharose (200 ml) at room temperature having specific rotation of polarized light alpha, acidified with 8 droplets of 90% acetic acid to which 65 mg of invertase enzyme were added and stirred to dissolve/disperse the enzyme. A mixture (150 ml) of the reagents were added immediately after mixing in a photochemical reactor having a source of ultraviolet (UV) light emitted from a low pressure 12 W mercury vapor lamp. The solution was immediately irradiated with UV and a flow of N2 was insufflated in the solution under irradiation. The remainder 50 ml of the starting solution, were not irradiated and were used as white or reference sample. The reaction of inversion was followed at a polarimeter both for the irradiated solution with UV and for the white sample. In the first 1000s of irradiation there were not relevant effects in the kinetics of the inversion reaction. However, after 15 minutes a considerable deceleration in the reaction speed of the irradiated solution whereas the solution not irradiated had a normal kinetic course. At 17 minutes of irradiation the enzymatic reaction was remarkably inhibited with respect to the white, but prolonged the irradiation (dark dots) after 17 minutes implying inhibition of enzymatic activity more completely.