Impact of ripening on the distribution of jackfruit polyphenol fractions and their inhibitory activities against metabolic enzymes

This study evaluated polyphenol fractions from unripe (J1), underripe (J2), and ripe (J3) jackfruit to explore stage-dependent industrial potential. Free (FP), conjugated (CP), and bound phenolics (BP) were isolated and assessed for antioxidant and enzyme inhibitory activities. Ripening significantly altered composition and bioactivity. CP antioxidant capacity and inhibition of α-glucosidase, pancreatic lipase, and xanthine oxidase increased progressively from J1 to J3, while FP and BP showed fluctuating trends. Ripe fruit (J3) exhibited the strongest CP-related bioactivities and a more diverse conjugated phenolic profile, whereas early stages had greater FP compositional complexity. Molecular docking supported these findings, identifying cyclomorusin as a potent ligand for α-glucosidase (−9.6 kcal/mol) and xanthine oxidase (−11.8 kcal/mol), and cyclokievitone for pancreatic lipase (−6.7 kcal/mol). These results demonstrate stage-specific functional differentiation and support targeted industrial utilization for health promotion.