Chan Seeds (Hyptis suaveolens L.) Storage Proteins: Isolation, Characterization, and Cytotoxic Effect on Three Cancer Cell Lines

Abstract

Since pre-Hispanic times, chan seeds (Hyptis suaveolens L.) have been used as food and in traditional medicine. However, there is still a lack of knowledge about the antioxidant capacity and cytotoxic effect of their storage proteins on cancer cells. Thus, these were investigated in this study. The total protein content of the seeds was 19.5% (dry base), and its protein fractions were confirmed via Tris-Tricine-SDS-PAGE electrophoresis as 43.1% glutelins, 30.9% albumins, 23% globulins, and 2.9% prolamins. The antioxidant capacity determined by ABTS showed the highest percentage of inhibition for the prolamins fraction of 23.6% (half-maximal inhibitory concentration [IC50]: 1.38 µg protein/mL) and the lowest percentage for the glutelins fraction of 6.3% (IC50: 4.51 µg protein/mL). The cytotoxic activity against the murine lymphoma L5178Y, human cervical (Hela), and colorectal (Caco-2) cell lines revealed that prolamin exerted superior inhibition on the Hela and Caco-2 cancer cells, with IC50 values of 0.49 and 0.44 mg protein/mL, respectively. This study underscores the potential of chan seed proteins as natural antioxidants and anticancer agents.