Development of a topical microemulsion from Ambrosia peruviana All. seeds with anti-inflammatory effect

Chronic inflammation significantly contributes to the development and progression of noncommunicable diseases, which account for a substantial portion of global mortality.While conventional anti-inflammatory drugs are effective, their long-term use is often restricted by side effects, prompting the search for safe and effective alternatives, such as phytotherapeutic products.The Colombian medicinal plant Ambrosia peruviana is known to exhibit antiinflammatory activity by inhibiting key mediators, including nitric oxide (NO•), tumor necrosis factor-α, interleukins (IL)-1β, and IL-6.This study's objective was to develop and characterize a stable topical microemulsion containing the anti-inflammatory seeds extract of A. peruviana to enhance its delivery and stability.The formulation utilized coconut oil (oil phase), polysorbate 80 (surfactant), and glycerin (co-surfactant).Using pseudoternary diagrams and a D-optimal design, the final composition was defined as 20% oil, 67% surfactant/co-surfactant (S/CoS), and 13% water.The microemulsion displayed desirable characteristics: a small droplet size of approximately 110 nm, good extensibility, low viscosity, and strong physical stability.Low conductivity confirmed the formation of an oil-in-water system.Crucially the formulation significantly reduced NO• production in LPS-stimulated RAW 264.7 macrophages without affecting cell viability, thus demonstrating that the anti-inflammatory activity of the extract was preserved within the delivery system.These findings support the use of the developed microemulsion as an innovative, stable, and effective carrier for the topical delivery of A. peruviana extract for managing chronic inflammation.