ALOX15-Inhibitory Peptides Derived from Coffee Bean Protein Hydrolysates Confer Neuroprotection against Lipid Peroxidation

Abstract Coffee beans are widely consumed worldwide and are known for their central nervous system-stimulating effects, mainly attributed to caffeine and other small molecules. However, the neuroprotective potential of coffee bean-derived peptides remains largely unexplored. In this study, coffee bean protein hydrolysates (CBPH) exhibited protective effects against RSL3- and 6-OHDA-induced neuronal injury. Virtual screening and molecular docking targeting 15-lipoxygenase (ALOX15), a key enzyme involved in oxidative neuronal damage, identified eight candidate inhibitory peptides. Among them, FAR and FPSFRE showed significant ALOX15 inhibitory activity, reducing enzyme activity by 51.73 ± 21.54% and 91.61 ± 2.43%, respectively (p < 0.05). Consistently, both peptides significantly improved neuronal viability and attenuated oxidative stress-induced injury. Their direct interactions with ALOX15 were further confirmed by cellular thermal shift assay and molecular dynamics simulations. Moreover, FAR and FPSFRE ameliorated locomotor deficits in a 6-OHDA-induced zebrafish model, highlighting their potential as natural neuroprotective agents and functional food ingredients.