Potential anti-inflammatory activities of gel prepared from leaf extract of Bryophyllum pinnatum (Lam.) Oken in Vietnam

Bryophyllum pinnatum (Lam.) Oken (fam: Crassulaceae) is widely used in folk medicine because of its promising anti- inflammatory, antibacterial, and wound healing properties. However, its application remains limited due to its instability and lack of clinical test and experimental authentication. This study was performed to develop a topical anti-inflammatory gel formulation from the leaf extract of Bryophyllum pinnatum to address the aforementioned issue. Different excipients for gel formulation, including carbopol 940, HPMC K4M, glycerin, and propylene glycol, were examined for their stability, using the gel uniformity, viscosity, and thickness. The obtained gel formulation was investigated for irritation effect using HET-CAM method. Finally, the gel anti-inflammatory activity was assessed using in vitro protein denaturation inhibition assay. As a result, a topical gel formulation was successfully developed with 0.8% pinnatum extract, 1% carbopol 940, 2.5% glycerin, 2.5% propylene glycol, sodium benzoate, triethanolamine and water. In vitro irritation test confirmed that the developed gel was non-irritating and exhibited promising in vitro anti-inflammatory activity, as reflected by an IC₅₀ value of 90.63±3.35 μg/mL. All together, a topical gel from B. pinnatum was successfully developed and proven for its safe application on anti-inflammatory problems.