Evaluation of Photoprotection and Anti-Aging Properties of Calamansi (Citrus microcarpa) Rind Extract in Sunscreen Formulation

The sun releases ultraviolet (UV) radiation, which, with prolonged exposure, may cause damaging effects on human skin. This led to the invention of Sunscreens used for photo-protection and for anti- aging from skin damage. However, most sunscreens readily available in the market are made from synthetic materials that have an environmental impact. This study investigates the photoprotective and anti-aging properties of calamansi (Citrus microcarpa) rind extract for potential sunscreen formulation. The research aims to explore the natural bioactive compounds present in the Calamansi rind that contribute to UV protection and anti-aging benefits, thereby offering a sustainable and eco- friendly alternative to synthetic sunscreens. High-Performance Liquid Chromatography (HPLC) and Ultraviolet-Visible (UV-Vis) Spectroscopy were employed to analyze the bioactive components and assess the extract's UV absorption capabilities. The primary bioactive compounds identified were Vitamin C and the flavonoid Quercetin, both known for their antioxidant and photoprotective properties. The anti-aging potential was evaluated through collagen assay using zebrafish (Danio rerio) as the model organism, while the toxicity of the extract was determined through zebrafish toxicity tests. The results revealed that the calamansi rind extract demonstrated significant photoprotective activity comparable to standard sunscreens in specific UV wavelengths (292, 294, and 296 nm). Furthermore, the collagen assay indicated the extract's effectiveness in promoting collagen production, confirming its anti-aging potential. The toxicity test showed no mortality in zebrafish up to a concentration of 2000 mg/L, indicating the extract's safety for potential cosmetic applications. Additionally, the stability test of the formulated sunscreen showed no significant changes in pH or physical appearance over a three-week period. This study concludes that calamansi rind extract is a promising natural ingredient for developing eco-friendly sunscreen with photoprotective and anti- aging properties. Future research is recommended to further optimize the formulation, extend stability testing, and explore the exact Sun Protection Factor (SPF) of the product.