NUTRITIONAL AND BIOACTIVE COMPOUNDS OF BRAZILIAN POPCORN CREOLE MAIZE

Brazilian creole popcorn varieties represent an important agrobiodiversity asset, notable for their genetic diversity and their nutritional, bioactive, and technological potential. This study evaluated the physical and bioactive properties of two creole popcorn varieties: yellow popcorn and purple popcorn. The kernels were ground in a blender to reduce particle size and subsequently analyzed for colorimetric parameters (L*, a*, and b*) and for total content and profiles of carotenoids and anthocyanins using high-performance liquid chromatography (HPLC). Data were subjected to analysis of variance and mean comparison using Student's t-test (p<0.01). Yellow creole popcorn exhibited higher lightness (L* = 57.11 for kernels and 71.59 for flour) and yellow intensity (b* = 20.83 for kernels), characteristics associated with the presence of carotenoid pigments, whereas purple creole popcorn showed lower L* (30.32 for kernels) and higher a* (10.11 for kernels and 9.35 for flour), reflecting its reddish-purple coloration. These differences are linked to pigment composition and distribution, given that carotenoids predominantly impart yellow hues, while anthocyanins contribute to red and purple colorations. Grinding increased the lightness of both varieties, likely due to the rupture of the pigmented pericarp and exposure of the endosperm, resulting in altered light scattering. Nine carotenoids were identified in both varieties, with a predominance of (all-E)-phytoene, (all-E)-zeaxanthin, and (all-E)-lutein; the levels of these compounds were higher in the yellow creole popcorn variety (p<0.01). The higher carotenoid concentration in the yellow creole popcorn (20.7 µg/g), compared to purple creole popcorn (12.5 µg/g), also resulted in a higher vitamin A activity equivalent (0.24 µg RAE/g), highlighting its potential as a source of compounds with provitamin A activity. Furthermore, lutein and zeaxanthin are nutritionally significant due to their role in protecting ocular tissues against damage associated with oxidative stress. In contrast, purple creole popcorn showed a higher total anthocyanin content (16.9 µg/g) than yellow popcorn (10.5 µg/g), with a predominance of cyanidin-3-glucoside (11.6 µg/g), consistent with its greater red intensity and lower lightness. Anthocyanins are phenolic compounds recognized for their antioxidant capacity and potential role in modulating processes associated with oxidative stress. Thus, the evaluated varieties exhibited complementary pigment profiles, yellow creole popcorn standing out as a source of carotenoids and potential provitamin A activity, and purple creole popcorn as a source of anthocyanins, thereby highlighting the importance of agrobiodiversity in obtaining corn varieties with distinct nutritional and bioactive attributes.

Acknowledgments

Coordination for the Improvement of Higher Education Personnel - Brazil (CAPES) - Funding Code 001 and for the scholarship (Process 88887.141456/2025-00), by the National Council for Scientific and Technological Development (CNPq) for the scholarship (Process 312660/2023-5), and to the São Paulo Research Foundation (Process N^o. 026/06378-5).