Bioactive Composition of Tropical Flowers and Their Antioxidant and Antimicrobial Properties.

This study evaluated tropical flower petals' bioactive compounds and antioxidant and antimicrobial properties. The physicochemical characteristics, carotenoids, phenolics, anthocyanins, organic acids, and antioxidant activity of 67 flowers were analyzed. In addition, the antimicrobial activity against , , and of 35 species was determined. A 2 × 3 experimental design was used for the extraction of carotenoids and phenolics, including solvents and ultrasonic agitation times. The mixture of methanol-acetone-dichloromethane (1:1:2) and acetone-methanol (2:1) resulted in the highest concentration of carotenoids, while acidified 80% methanol favoured phenolic extraction. was extremely rich in carotenoids (292.5 mg β-carotene/g DW), in anthocyanins (7.35 mg C-3-gl/g DW), while a high content of citric acid was found in (17,819 mg/100 g DW). On the other hand, showed the highest antioxidant activity (7.8 mmol Trolox equivalent/g DW). The main phenolics were -coumaric acid in (12,044 mg/100 g DW), 4-hydroxybenzoic acid in (10,729 mg/100 g DW), and kaempferol in (8236 mg/100 g DW). The extract of , , and showed antibacterial activity, while the extract of was the only one active against . These findings highlight the potential health benefits from certain tropical flowers.