Effect of germination and UV-B elicitation on chemical compositions, antioxidant activities, and phytochemical contents of underutilised Mexican blue maize seeds

Abstract

Germination improves seed functionality due to increased phytochemicals and associated antioxidant activities. These effects are enhanced with a suitable inductor which is applied at appropriate time and dose. The aim of the present work was to evaluate the effect of germination + UV-B elicitation on the chemical compositions, antioxidant activities (AoxA), total phenolic (TPC), total anthocyanin (TA), and γ-aminobutyric acid (GABA) contents in blue maize seeds. The application of UV-B radiation (wavelengths of 280 - 311 nm) during 37.0 h was an effective elicitor. Germinated-elicited blue maize flour (GEBMF) had higher proteins (+29.1%), dietary fibres (+22.0%), and AoxA (ABTS: +133.9%; DPPH: +173.4%) than unprocessed blue maize flour (UBMF). The increase in AoxA was closely related to the observed increase in TPC (+587.2%), TA (+29.9%), and GABA (+199.9%). Therefore, GEBMF could be used as a source of proteins, dietary fibres, and natural antioxidants in the formulation of new functional foods and beverages. These results could also contribute to the use and conservation of blue maize, an underutilised cereal.