Enhancement of antioxidant and anti-inflammatory activities in carrot (Daucus carota L.) leaf extracts through Jeju lava seawater addition

Jeju lava seawater, a circulating resource, is saline groundwater rich in minerals.This study examined the impact of adding electrodialyzed lava seawater (ELW) on the antioxidant and anti-inflammatory activities, as well as the composition of carrot leaf extracts.Hot water extracts containing ELW in distilled water (H-ELW) were prepared by varying the ELW content at a ratio of 0, 15, and 30% (H-ELW 0%, H-ELW 15%, H-ELW 30%).Among these, H-ELW 15% exhibited superior antioxidant and anti-inflammatory effects.Specifically, H-ELW 15% reduced more DPPH and ABTS radicals than both H-ELW 0% and H-ELW 30%.In cell-based experiments, H-ELW 15% further reduced reactive oxygen species and nitric oxide production, as well as the expression of inflammation markers, including inducible nitric oxide synthase, cyclooxygenase 2, and tumor necrosis factor-α at both the mRNA and protein levels, compared to the other extracts.Component analysis identified rutin, catechin, caffeic acid, chlorogenic acid, and cynaroside in the extracts.The quantities of these compounds were significantly higher in the H-ELW 15% and H-ELW 30% extracts compared to H-ELW 0%.Notably, chlorogenic acid, caffeic acid, and cynaroside were most abundant in the H-ELW 15% extract, suggesting that these compounds likely contributed to the enhanced antioxidant and anti-inflammatory activities.These findings indicate that ELW can be effectively utilized to prepare optimal extracts with enhanced antioxidant and anti-inflammatory properties, making it a valuable component in the extraction process.