Hydrolyzed collagen from defatted sea bass skin and its conjugate with epigallocatechin gallate: In vitro antioxidant, anti-inflammatory, wound-healing and anti-obesity activities

The in vitro antioxidant, anti-inflammatory, wound-healing and anti-obesity activities of hydrolyzed collagen (HC) from defatted sea bass (Lates calcarifer) skin and HC conjugated with epigallocatechin gallate (EGCG) were comparatively studied. HC and HC-EGCG conjugate at all levels (1.25-10 mg/mL) had H2O2 scavenging activity, but the conjugate was more active at all levels (P < 0.05). Both samples (50-200 mu g/mL) exhibited antiinflammatory activity by inhibiting nitric oxide and tumor necrosis factor-alpha production in lipopolysaccharideinduced RAW264.7 cells but HC at 200 mu g/mL exhibited the highest inhibitory activities (P < 0.05). When HaCaT keratinocyte cells were treated with both samples, no significant (P < 0.05) cytotoxicity was found at all levels (50-200 mu g/mL). Moreover, HC at 200 mu g/mL stimulated the highest level of cell migration (P < 0.05), which reflects a better wound healing effect. The HC-EGCG conjugate at 5.0-6.25 mg/mL showed stronger inhibitions of alpha-amylase and alpha-glucosidase activities and had potentially better anti-diabetic effect than HC (P < 0.05).