Unveiling antioxidant arsenal DPPH radical scavenging activity and flavonoid profiles of six edible flower infusions

Free radicals contribute to the onset of various diseases, including aging, cancer, and cardiovascular conditions. The body mitigates free radicals through enzymatic synthesis of antioxidants and dietary intake of antioxidants such as vitamin E and flavonoids. This study investigated the antioxidant activity and total flavonoid content of aqueous extracts from six edible flowers: tropical species (marigold, honeysuckle, champaka) and temperate species (lily, peach, carnation). Phytochemical screening, DPPH radical scavenging assays, and total flavonoid quantifications were conducted. All extracts contained flavonoids and tannins, with carnation exhibiting the most diverse phytochemical profile. Champaka demonstrated the strongest antioxidant activity (IC50 = 43.33 ± 7.31 μg/mL), while carnation had the highest total flavonoid content (1795.90 ± 120.01 mg quercetin equivalent/g extract). Tropical flowers generally displayed stronger antioxidant activities, whereas temperate flowers exhibited higher flavonoid contents. However, no statistically significant correlation was observed between antioxidant activity and flavonoid content across all extracts (p > 0.05). These findings underscore the complexity of relationships between phytochemical composition and antioxidant potential, highlighting edible flowers as valuable natural antioxidant sources. Comprehensive phytochemical profiling and multi-assay approaches are crucial for evaluating plant-based antioxidant properties.