Protective Effects of Crude and Light Fraction Patchouli Oil Against UVB-Induced Dermal Aging in Mice: In silico and In Vivo Study

Patchouli oil has gained significant interest due to its antioxidant and anti-aging properties, making it a potential natural ingredient in skincare formulations. This study investigated the protective effects of crude patchouli oil (CPO) and its light fraction (CPO1) against UVB-induced skin aging in Balb/c mice. Mice were exposed to UVB radiation (498 mJ/cm²) for two weeks (5 days per week), followed by topical treatment with CPO or CPO1. Skin aging parameters, including elasticity, moisture, collagen content, epidermal thickness and fibroblast count, were evaluated. FTIR spectroscopy confirmed the presence of bioactive functional groups, such as hydroxyl, aliphatic and carbonyl groups, in both CPO and CPO1. Results demonstrated that both CPO and CPO1 improved skin elasticity, increased moisture levels, enhanced collagen synthesis and restored fibroblast numbers compared to the untreated UVB-exposed group. Notably, CPO1 exhibited the most significant anti-photoaging effects, with increased collagen fiber content (40.83%), skin elasticity (12.30%), and moisture level (24.73%). Additionally, molecular docking studies revealed that acetic acid, a compound in patchouli oil, showed strong binding affinity to MMP9 (–7.1 kcal/mol), with molecular dynamics simulations confirming stable ligand-protein interactions and the highest number of hydrogen bonds (282). These findings highlight the potential of patchouli oil, particularly its light fraction, as a promising anti-photoaging agent that mitigates UVB-induced skin damage and inhibits MMP9 activity. Further research is recommended to validate its molecular mechanisms and explore its application in human skincare products. HIGHLIGHTS Crude patchouli oil (CPO) and its light fraction (CPO1) can protect against UVB-induced skin aging in mice. Both CPO and CPO1 improved skin elasticity, increased moisture levels, enhanced collagen synthesis and restored fibroblast numbers in UVB-exposed mice. CPO1 showed the most significant anti-photoaging effects, increasing collagen fiber content (40.83%), skin elasticity (12.30%) and moisture level (24.73%). Acetic acid, a compound in patchouli oil, binds strongly to MMP9, an enzyme involved in skin aging. GRAPHICAL ABSTRACT