Choline chloride-based deep eutectic solvent properties and its anti-tyrosinase activity: Insight for cosmetical applications

• Physical properties had weak correlation and no significance to anti-tyrosinase. • pH had strong negative correlation and high significance to anti-tyrosinase. • HBD of polyol and sugar groups possessed no tyrosinase inhibition. • HBD of organic acid groups possessed high tyrosinase inhibition. • Anti-tyrosinase power: ChCl:Sor<ChCl:Gly<ChCl:PG<ChCl:Fru<ChCl:LV<ChCl:LA. Deep eutectic solvents (DES) have great potential as the future solvents in various fields including cosmetics. Cosmetics industry has shifted into green chemistry to fulfill market demand and also give alternative composition with good sustainability. DES not only used as extraction solvent but also enhances the performance as the cosmetic ingredient itself. The study of anti-aging prevention becomes the current interest with one of the subjects is tyrosinase inhibition which has an important role in melanin synthesis in melanocyte. This study found that the DES parameter of viscosity, density and refractive index didn’t affect the tyrosinase inhibition. However, pH parameter had strong negative correlation and high significance towards tyrosinase inhibition. DES with HBA choline chloride (ChCl) combined with HBD propylene glycol (PG), lactic acid (LA), levulinic acid (LV), glycerol (Gly) and fructose (Fru) showed tyrosinase activity with the order of inhibition power ChCl:Sor<ChCl:Gly<ChCl:PG<ChCl:Fru<ChCl:LV<ChCl:LA. DES with organic acid HBD LA and LV has the highest tyrosinase inhibition by 97.17% and 96.09% respectively which was comparable with kojic acid as positive control. Accordingly, the selection of HBDs requires careful consideration in alignment with the intended objectives to ensure optimum application.