Physiological Activity and Functional Properties of Ixeris dentata Hot Water Extracts: Potential for Use as Cosmetic Ingredients

Purpose: This study analyzed the physiological activity, cytotoxicity, anti-inflammatory, and whitening effects of hot water extracts from the roots and leaves of Ixeris dentata to determine the optimal extraction conditions. Further, their potential as functional cosmetic materials were evaluated.Methods: Extracts were obtained from wild and cultivated I. dentata leaves and roots using hot water (room temperature to 100°C). The antioxidant activity, bioactive compound content (total phenolic content (TPC), and total flavonoid content (TFC), cytotoxicity, anti-inflammatory effects, and whitening effects (tyrosinase activity and DOPA oxidation inhibition) were evaluated. Results: The optimal extraction conditions were determined as 100°C and 90°C for the leaves and roots, respectively. The DPPH radical scavenging activity of the leaf extracts ranged as 90-94%, with TPC and TFC values of 6.78±0.11 mg GAE/g mass and 6.06±0.70 mg QE/g mass, respectively. The bioactive compound content was higher in the leaves than in the roots, wild plants compared to cultivated plants, and summer-harvested compared to spring-harvested . Further, room-temperature extraction yielded the highest bioactive compound content from the leaves within 24 h, whereas the root extracts had lower yields. The wild leaf extract exhibited 6.14±2.91% tyrosinase inhibition and 68.9±18.4% DOPA oxidation inhibition. Furthermore, the extracts demonstrated low cytotoxicity (>90% cell viability at 100 μg/mL) and an 8.2% TNF-α inhibition rate. Conclusion: The optimal hot water extraction conditions for I. dentata were established. The results confirmed its antioxidant, whitening, and anti-inflammatory properties with low cytotoxicity. The findings of this study indicate the potential applications of I. dentata extracts in the cosmetics, medical, and food industries without additional concentration processes.