Objective: The objectives of this study were to quantify γ-oryzanol in an ethanolic extract of Oryza sativa L. Indica (black rice) bran and to evaluate its activity as a tyrosinase inhibitor.
Methods: Black rice bran was extracted via maceration in 96% ethanol, and the γ-oryzanol concentration in the extract was measured through high-performance liquid chromatography. The applicability of the extract as a skin lightening agent was determined by evaluating its tyrosinase inhibition activity.
Results: The dry rice bran contained 118.572 mg/g of γ-oryzanol, and the extract inhibited tyrosinase activity at an IC50 of 74.8%.
Conclusion: The black rice bran extract was sufficiently potent for use in skin lightening formulations