Evaluation of Ligusticum jeholense Extracts for Skin Lightening

Natural materials in facial prescriptions has been practiced for thousands of years in China. Natural plant extracts are increasingly used in skin-whitening products. We found Gao-Ben (the rhizome and root of Ligusticum jeholense Nakai et Kitag, GB) was a common herb used in external whitening prescriptions by retrieving ancient Chinese medicine texts and modern traditional Chinese medicine(TCM) documents. Then, the functions of GB in topical application prescriptions for skin lightening were investigated. The essential oil of GB (GBO) were extracted by supercritical CO2fluid extraction (SFE-CO2), with the yield being 1.5%. The oil ingredients were analyzed by gas chromatography-mass spectrometry (GC-MS), and benzyl alcohol and ligustilide were major constituents, their relative contents were 55.3% and 35.7%. Then the enhanced penetration effects of GBO on test compounds, ferulic acid and ligustrazine were tested using the Franz diffusion cell. Finally, the changes in morphological features of rat skin treated with GBO were researched by computer-aided image analysis of haematoxylin and eosin (H&E) staining. This study indicates GBO can enhance skin penetration by changing the structure of the stratum corneum barrier. Therefore, the active components could be absorbed through the topical skin and exert the whitening effect.