Influence of drying and cooking process on the phytochemical content, antioxidant and hypoglycaemic properties of two bell Capsicum annum L. cultivars

The present study evaluates the influence of drying and cooking processes on the health properties of two bell Capsicum annuum L. cultivars Roggiano and Senise compared with fresh peppers. The content of phytochemicals decreased in the order fresh > dried > dried frying processes. HPLC analysis was applied to quantify five flavonoids from peppers. Apigenin was identified as main constituent. Its content was affected by drying and dried frying processes. The antioxidant activity was evaluated by DPPH, ABTS, β-carotene bleaching test and Fe-chelating activity assay. A comparable radical scavenging activity was observed for both cultivars. Interestingly, frying process did not influenced this property. Roggiano peppers exhibited the highest antioxidant activity using β-carotene bleaching test with IC50 values of 38.1 and 24.9 μg/mL for total extract and n-hexane fraction, respectively. GC–MS analysis of lipophilic fraction revealed the presence of fatty acids and vitamin E as major components. In the inhibition of the carbohydrate-hydrolyzing enzymes fresh Senise peppers exerted the strongest activity against α-amylase with an IC50 value of 55.3 μg/mL. Our results indicate that C. annuum cultivars Roggiano and Senise have an interestingly potential health benefits not influenced by processes that are used before consumption.