Arctigenin-Enriched Burdock Seed Oil (ABSO): A New Skin Brightening Botanical Extract

Abstract

The Arctium lappa L. plant, commonly known as burdock, has been used therapeutically for hundreds of years. Arctigenin (ATG) is an active ingredient in burdock, albeit at low quantities or mostly in the form of acrtiin (arctigenin-4-glucoside). ATG has been touted for its anti-inflammatory properties in many cell types and disease states; however, its role in skin and melanin production has not been extensively studied. Our aims for this study were to develop a burdock seed extract enriched for ATG that is amenable to quasi-drug development, determine in vitro brightening activity, and evaluate safety and skin brightening efficacy clinically in human subjects. Arctiin and ATG content were measured by high-performance liquid chromatography (HPLC). In vitro studies utilized EpiDermTM tissues for skin irritation test, and MelanoDermTM tissues for melanin reduction capacity. A 45 subject clinical study was performed in adult subjects ranging in age from 30 to 60 years old (mean = 41.9 ± 6.7) to test the safety and skin brightening potential of 1% ABSO lotion. We demonstrate by HPLC that ABSO is a natural extract that contains ~5-times more arctigenin than BSO. Furthermore, ABSO inhibits melanin production better than BSO and retains the same melanin-reducing capacity as synthetic ATG in vitro in MelanoDerm™ 3D skin cultures. ABSO also adheres to quasi-drug criteria according to the Japanese Standards of Quasi-Drug Ingredients as determined by infrared absorption spectrum method, unsaponifiable matter, heavy metal and arsenic content, and acid, saponification, and iodine value methods. Clinical assessment of 1% ABSO lotion shows it is well-tolerated in human skin and demonstrates improved brightness and skin tone evenness. ABSO is a natural arctigenin-enriched burdock seed extract that reduces melanin content in vitro and clinically improves skin brightness.