Phytochemical Profiling and Anti-Inflammatory Activity of Rubus parvifolius Leaf Extract in an Atopic Dermatitis Model

This study investigated the anti-inflammatory effects of <i>Rubus parvifolius</i> leaf (RPL) extract, and its phytochemical composition was characterized using LC-MS/MS and HPLC analyses. In an inflammation model using HaCaT keratinocytes, treatment with RPL extract led to a significant reduction in inflammatory markers, indicating strong anti-inflammatory activity. Phytochemical analysis revealed that the extract is rich in flavonoids, with quercetin 3,7-diglucoside (12.73 mg/g DW) as the most abundant compound, followed by hirsutrin (4.74 mg/g DW) and ellagic acid (1.58 mg/g DW). Kaempferol 3-<i>O</i>-glucuronide was detected in lower amounts (0.31 mg/g DW), and tiliroside was present only in trace levels. These compounds are well known for their antioxidant and anti-inflammatory properties, suggesting that RPL extract may exert multiple beneficial effects on skin health. Collectively, these findings support the potential of RPL extract as a natural therapeutic agent for managing skin inflammation, particularly in conditions such as atopic dermatitis, with its efficacy likely attributed to the high levels of quercetin 3,7-diglucoside, hirsutrin, and ellagic acid. However, the present work was confined to in vitro experiments, and the mechanistic pathways were not experimentally validated. Future in vivo studies are needed to confirm these findings.