Keywords: Pepitas, Phenolic phytochemicals, Antioxidant, Roasting treatment
Pumpkin seed (Cucurbita pepo) otherwise known as pepitas serves as food and has several medicinal uses in many parts of the world. This study investigated the effect of roasting on the phenolic phytochemicals and antioxidant activities of pumpkin seeds. Reverse-phase HPLC analysis revealed that the seed had appreciable levels of caffeic acid, quinine, rutin, quercetin, and chlorogenic acid. Roasting caused a significant (P < 0.05) increase in the polyphenolic content; reducing power, iron-chelating ability, DPPH* (2,2 diphenyl-1-picrylhydrazyl radical), ABTS*+ [2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) radical cation], NO* (nitric oxide radical), OH* (hydroxyl radical) scavenging abilities; and SNP- (sodium nitroprusside) and Fe2+-induced lipid peroxidation inhibitory capacity of the seed extract. Thus, roasting enhanced the levels of these functional attributes of the seeds due to the release of phenolic phytochemicals, hence contributing to the health-promoting and disease preventing abilities of pepitas.