Formulation and In Vitro Anti-Aging Activity Testing of Nyamplung (Calophyllum inophyllum L.) Leaf Extract Cream

Oxidative stress caused by high levels of free radicals is a primary trigger for premature skin aging. Nyamplung leaves (Calophyllum inophyllum L.) are rich in bioactive compounds, making them highly promising for development as natural ingredients in antioxidant and anti-aging cosmetic products. This study aimed to formulate creams using nyamplung leaf extract at concentrations of 1% and 1.5%, assess their physical characteristics, and evaluate their anti-aging potential in vitro. The laboratory study employed a stepwise Soxhlet extraction method using ethyl acetate as the solvent prior to formulating the extract into creams. Physical quality testing included organoleptic assessment, homogeneity, pH, spreadability, emulsion type, viscosity, and accelerated stability testing (cycling test). Meanwhile, anti-aging activity was evaluated in vitro by measuring tyrosinase enzyme inhibition (dopachrome method) using a UV-Vis spectrophotometer. The ethyl acetate extraction yielded 4.89%. All cream formulations met the physical quality standards for topical preparations, exhibiting homogeneity, stability during the cycling test, a pH range of 5.07–5.18, spreadability of 4.9–5 cm, an oil-in-water (O/W) emulsion type, and appropriate viscosity levels. Anti-aging efficacy tests demonstrated tyrosinase enzyme inhibition rates of 20.83% at a 1% extract concentration and 5.42% at a 1.5% concentration.and demonstrated in vitro anti-aging activity, with the 1% concentration formula exhibiting higher tyrosinase inhibition activity than the 1.5% formula.