<![CDATA[Background: Natural sunscreen development has gained increasing attention because bioactive compounds from medicinal plants possess antioxidant activity with lower irritation potential than synthetic UV filters. Catharanthus roseus leaves contain flavonoids and other phenolic compounds with potential photoprotective activity; however, these compounds are susceptible to degradation by light, heat, and oxidation. Complex coacervation microencapsulation offers an effective approach to improve the stability and performance of natural active ingredients. Purpose: To analyze the effect of different concentrations of bleached ethanol extract microcapsules of Catharanthus roseus prepared by complex coacervation on the physical characteristics and Sun Protection Factor (SPF) of sunscreen cream. Method: This true experimental study employed a Completely Randomized Design (CRD) with three concentrations of microcapsules. The extract was obtained using Ultrasonic Assisted Extraction, followed by bleaching with activated charcoal and microencapsulation using gelatin and sodium alginate through the complex coacervation method. The resulting microcapsules were characterized for encapsulation efficiency and particle size before being formulated into sunscreen cream. Physical quality evaluations included organoleptic properties, homogeneity, pH, spreadability, adhesiveness, viscosity, photostability, and SPF. SPF data were analyzed using One-Way ANOVA followed by Tukey HSD at a significance level of p < 0.05. Results: Formula F3 showed the highest encapsulation efficiency (6.64%) with an average particle size of 1.97 µm. All formulations met the physical quality requirements for topical creams. SPF values increased with increasing microcapsule concentration, reaching 2.66 (F0), 3.41 (F1), 5.57 (F2), and 6.45 (F3). One-Way ANOVA demonstrated a significant effect of microcapsule concentration on SPF values (p = 0.000). Formula F3 also exhibited the best photostability. Conclusion: Different concentrations of bleached Catharanthus roseus ethanol extract microcapsules prepared by complex coacervation significantly improved the physical characteristics and sunscreen effectiveness of the cream formulation. Keywords: Catharanthus Roseus; Complex Coacervation; Microencapsulation; Sun Protection Factor; Sunscreen Cream.]]>
