4.5.3. Catalase Activity

CAT activity was evaluated in the plasma of peripheral blood. Twenty-five μL samples were centrifuged at 1000× *g* for 10 min at 4 ◦C to obtain plasma. The activity of CAT was evaluated according to the instructions for the Cayman Chemicals Catalase Assay (No. 707002; Ann Arbor, MI, USA). This kit uses the peroxidation function of CAT to determine enzyme activity. The absorbance was read at 540 nm in a Multiskan™ FC microplate reader (Thermo Scientific™, Vantaa, Finland). One unit of CAT was defined as the amount of enzyme that induced the formation of 1 nmol of formaldehyde/min. CAT activity was measured in duplicate (per sample) and according to the CAT standard curve.
