Formulation and Physicochemical Stability Evaluation of a Polyherbal Cream Incorporating Turmeric, Neem, Green Tea, and Aloe Vera Extracts

Background: Skin aging is a multifactorial biological process driven by intrinsic factors such as genetic changes and hormonal decline, and extrinsic factors, primarily ultraviolet (UV) radiation, that trigger oxidative stress, chronic inflammation, collagen degradation by matrix metalloproteinases (MMPs), and progressive loss of skin hydration. Growing consumer concern over the adverse effects of synthetic anti-aging products has driven a shift toward plant-based formulations.Objectives: This study aimed to develop and physicochemically evaluate a polyherbal cream incorporating Curcuma longa (turmeric), Azadirachta indica (neem), Camellia sinensis (green tea), and Aloe vera extracts, selected for their complementary antioxidant, anti-inflammatory, wound-healing, and moisturizing properties reported in the literature, as a candidate formulation for further anti-aging investigation.Methods: Four oil-in-water (O/W) emulsion formulations (F1-F4) were prepared using decoction and sonication extraction methods and evaluated for physical appearance, pH stability over 30 days, temperature stability (4, 25, and 40°C), freeze stability (4 ± 2°C for one month), and 24-hour patch irritancy.Results: Physical evaluation identified formulation F4 as superior in appearance and consistency. pH monitoring confirmed all formulations maintained skin-compatible values (6.0-6.5), with F4 showing the most stable pH (6.5). No phase separation occurred under any temperature condition, and freeze-stability testing confirmed no changes in color, odor, texture, or homogeneity. All four formulations were non-irritant, producing no erythema or edema.Conclusion: The developed polyherbal cream is physicochemically stable and dermally safe, with formulation F4 demonstrating the best overall performance. Antioxidant assays (e.g., DPPH radical scavenging), ex vivo skin-permeation studies, and in vivo efficacy trials are required to substantiate anti-aging efficacy before any therapeutic or commercial claims can be made.