Evaluation of Sapindus mukorossi Gaertn Flower Water Extract on In Vitro Anti-Acne Activity

Background: Sapindus mukorossi Gaertn is a deciduous tree with saponins as the main active ingredients and has been utilized in medicine and cosmetic industries. Currently, the investigations of S. mukorossi mainly focus on the pericarp and seed kernel parts, while other parts are yet to be studied and developed. This study aimed to investigate the anti-acne potential of S. mukorossi flower water extract (SMFW) by in vitro experiments. Methods and Results: The DPPH, ABTS, superoxide anion radical scavenging assay, and FRAP assay revealed the strong antioxidant activities of SMFW. The antibacterial activity of SMFW against Cutibacterium acnes has been evaluated with an inhibition diameter of 14.08 ± 0.63 mm. Furthermore, SMFW significantly inhibited the secretion of pro-inflammatory cytokines (TNF-α, IL-6, and IL-β) in lipopolysaccharide (LPS)-stimulated THP-1 macrophages. Transcriptome analysis showed that SMFW treatment reversed 448 LPS-upregulated DEGs and 349 LPS-downregulated DEGs, and KEGG enrichment analysis indicated that SMFW might exert its anti-inflammatory effect via NOD-like receptor and JAK-STAT signaling pathways. Conclusions: SMFW exhibited antioxidant, antibacterial, and anti-inflammatory properties in in vitro experiments. RNA-seq analysis indicated that SMFW may alleviate inflammation by regulating the NOD-like receptor and JAK-STAT signaling pathways. In summary, SMFW has shown potential for anti-acne efficacy and can be used as a natural raw material in cosmetics.