Formulation and evaluation of polyherbal sunscreen cream enriched with natural antioxidant

Background: Ultraviolet (UV) radiation is a major environmental factor contributing to oxidative stress and premature skin ageing. The increasing interest in plant-based skincare has encouraged the development of herbal sunscreen formulations containing naturally derived antioxidant and photoprotective constituents. The present study aimed to develop a polyherbal sunscreen cream incorporating Anacardium occidentale (Cashew apple) extract, Clitoria ternatea (Shankhpushpi) extract, and Tamarindus indica. L (Tamarindus seed polymer) Extract for potential photoprotective and antioxidant benefits. Materials and Methods: Cashew apple and Shankhpushpi extracts were prepared using suitable extraction methods, while Tamarindus indica seed polymer was extracted and incorporated as a natural thickening and stabilizing agent. Preliminary phytochemical screening was performed on the selected on respective extracts. Four formulations (F1–F4) were prepared with varying concentrations of the herbal ingredients and polymer. The formulations were evaluated for physical appearance, homogeneity, pH, spreadability, viscosity, extrudability, washability, microbial quality, stability, antioxidant activity and in-vitro SPF. Results: All four formulations showed a smooth, homogeneous semisolid appearance with no visible phase separation. The pH values ranged from 5.5 to 6.0, while spreadability and extrudability were satisfactory. No visible microbial growth was observed in any formulation under the tested conditions. Preliminary iodine-based antioxidant screening demonstrated antioxidant potential, where F3 showed the greater colour change. In-vitro SPF values were 24.52,23, 30 and 20.52for F1, F2, F3 and F4, respectively. F3 showed the highest SPF of 30, indicating comparatively better photoprotective activity among the formulations. Conclusion: The study demonstrated that Cashew apple extract, Shankhpushpi extract and Tamarindus indica seed polymer can be successfully incorporated into a polyherbal sunscreen cream with acceptable physicochemical characteristics and promising antioxidant and photoprotective potential. Among the formulations, F3 was identified as the most promising formulation based on the overall evaluation and its highest SPF value of 30. Further studies involving standardized SPF evaluation, short term stability, safety assessment and in-vivo investigation are recommended to establish its potential for further development.