Exploring the potential of sesamol/asarinin-enriched sesame oil in skin lightning and wound repair

Sesame oil enriched with sesamol (SRO)/asarinin (ARO) is obtained by a catalytic process. • SRO and ARO show distinct lignan profiles and skin-protective activities from CSO. • SRO showed strongest skin lightning efficacy via tyrosinase inhibition. • ARO exhibited the best overall skin wound repair efficacy in zebrafish assays. • Lignan-enriched processing technology enhances the skin care efficacy of sesame oil. Driven by the demand for natural skincare actives, this study explored high-value applications of functional sesame oil by utilizing processing-induced endogenous lignan conversion. A controlled solid-acid catalytic process was employed to convert cold-pressed sesame oil (CSO) into sesame oil enriched with either sesamol (SRO) or asarinin (ARO), without significantly altering the fatty acid composition. Meanwhile, the content of γ-tocopherol and the major phytosterols decreased after catalytic treatment, with no significant difference observed between SRO and ARO. In vitro and in vivo comparative evaluations revealed the unique bioactivities of the three oils. SRO showed remarkable skin-lightning potential, exceeding CSO by 88.9 percentage points in mushroom tyrosinase inhibition at 1000 μg/mL. Zebrafish assays confirmed that SRO suppresses melanin expression via tyrosinase inhibition. Molecular docking suggests that sesamol in SRO may inhibit catalytic activity by interacting with key histidine residues in the catalytic center of tyrosinase. Meanwhile, ARO displayed superior wound repair efficacy, improving tail fin regeneration efficacy by 44% and 56% relative to SRO and CSO, respectively. In contrast, SRO exhibited stronger anti-inflammatory activity at low concentrations (5 mg/mL), with a 65% higher neutrophil clearance efficacy than CSO. CSO consistently showed the weakest effects. The distinct bioactivities between SRO/ARO and CSO are plausibly linked to their differential lignan profiles, particularly the enrichment of sesamol and asarinin. These findings suggest that processing-induced endogenous lignan conversion is an effective strategy for selectively modulating the biological functions of sesame oil, thereby enhancing its application value. Download: Download high-res image (512KB) Download: Download full-size image