Red-jambo (Syzygium malaccense): Bioactive compounds in fruits and leaves

- Antioxidant capacity of different tissues of Syzygium malaccense.
- Three anthocyanins were identified in the fruit peel.
- Sixteen polyphenols were quantified in red-jambo fruit.
- Leaves showed expressive hydrophilic antioxidant capacity.

Syzygium malaccense is poorly studied regarding the bioactive compounds of fruits and leaves. The aim of this study was to determine proximate composition, phenolic compounds, carotenoids, and antioxidant capacity of the fruit parts and leaves of S. malaccense. The samples were extracted with different solvents in order to analyze phenolic compounds content (Folin-Ciocalteau and HPLC-DAD/FLD), flavonoids (reaction with AlCl3 and HPLC-DAD/FLD), anthocyanins (differential pH and HPLC-DAD, UPLC-ESI-MS/MS), total carotenoids (colorimetric method) and antioxidant capacity (hydrophilic and lipophilic-ORAC, FRAP, DPPH). The pulp demonstrated high amounts of soluble fibers and reducing sugars. The peel, seeds and leaves of S. malaccense showed great contents of phenolic compounds, flavonoids and carotenoids as well as antioxidant capacity. The anthocyanins found in the fruit were cyanidin-3-O-glucoside, cyanidin-3,5-O-diglucoside, and peonidin-3-O-glucoside. Polar bioactive compounds showed strong correlation to hydrophilic antioxidant capacity, while carotenoids did not correlate lipophilic-ORAC.