CATALASE ENZYME ACTION IN DIFFERENT EVERYDAY FOODS: AN EXPERIMENTAL DIDACTIC APPROACH TO BIOLOGY TEACHING

Abstract

This study proposes an experimental activity for teaching Cell Biology in high school, exploring the action of the catalase enzyme in different everyday foods. As a methodology, simple everyday materials were used, such as fruits, vegetables, and even raw bovine liver. To determine the action of the catalase enzyme, the foods were cut into small pieces using a blunt knife, and approximately 3 mL of 3% Hydrogen Peroxide (H₂O₂) was applied to their surface using a dropper, Pasteur pipette, or graduated syringe. As the main result, it was observed that the tested foods exhibited a positive reaction, with variations in the intensity of effervescence, indicating different catalase concentrations in the tissues. The positive reaction occurred due to the degradation of H₂O₂ by the catalase enzyme, which is naturally stored in the peroxisomes of cells. Cutting the foods exposed the catalase enzyme, allowing its direct interaction with H₂O₂, transforming this compound into gaseous oxygen (effervescent bubbles), water, and heat. This reaction is called decomposition, and because it releases heat, it is classified as exothermic, protecting organisms from the toxic effects of H₂O₂, preventing oxidative stress and possible DNA mutations. Thus, the experimental activity proposed in this study can serve as an excellent methodological teaching resource, facilitating and stimulating student learning while enhancing the perspective of scientific experimentation.