Figure 3. Antioxidant changes (RS) induced previous thermal denaturation.

A cyclic pattern of antioxidant changes may be observed just before protein aggregation. Protein stock solutions (100 mg/ml) were placed at 65±0.1°C and samples were collected several seconds before the denoted protein aggregation (scattering at 400 nm). A characteristic cyclic pattern of increased and decreased antioxidant capacity could be observed before protein aggregation. The antioxidant capacity (AC) of the albumin previously placed at 65°C was 94 nM TEU and corresponds to 100% of ACA%. RS correspond to ACA%-100 as specified in the Material and Methods section. The increase and decrease of ACA did not exceed 10% of the base antioxidant level. The graph corresponds to a representative experiment. ¹Temperature for aggregation is concentration-dependent (more details in the text).