Formulation of the serum gel containing green coffee bean (Coffea robusta l) extract as an antioxidant and tyrosinase enzyme inhibitor

Abstract

People who expose to the sun might develop hyperpigmentation or skin spots. Hyperpigmentation is caused by an enzymatic reaction such as tyrosinase and could be reduced by using a sunscreen product. Many studies reported that coffee has antioxidant activity, especially green coffee. Its natural sources such as caffeine, chlorogenic acids, and phenolic compounds are known as potential antioxidants. This research, therefore, aims to formulate and evaluate green coffee bean (Coffea robusta L) extract in serum gel as antioxidants and tyrosinase enzyme inhibitors. The phenolic total of the green coffee bean (GCB) was conducted by Folin-Ciocalteu assay. The antioxidant activity was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, and tyrosinase enzyme L-Tyrosine as substrate. The GCB extract and kojic acid were formulated into serum gel dosage form and evaluated for physical stability. The result showed that the total phenol of GCB extract was 9.51 gGAE/100g, while its antioxidant activity and tyrosinase enzyme had an IC50 value of 4.02 μg/mL and 580.19 μg/mL, respectively. Based on physical stability, it remained stable after 28-day storage with an antioxidant and tyrosinase enzyme inhibitory with IC50 values 19.88 μg/mL and 702.26 μg/mL, respectively. In conclusion, this study showed that the serum gel dosage form of GCB extract could be used to face lightening products.