PHARMACOLOGICAL ASSESSMENT OF LACTUCA SATIVA EXTRACT AND DEVELOPMENT OF A MICROSPHERE-BASED SUSTAINED RELEASE ANTI-INFLAMMATORY GEL

Abstract

The present study evaluates the pharmacological potential of Lactuca sativa L. extract and its application in a microsphereloaded sustained release gel formulation. Antiinflammatory activity was assessed using the formalin-induced paw edema model in mice, while the elevated plus maze test was employed to examine anxiolytic effects. Microspheres were prepared via solvent evaporation using a water-in-oil-in-water multiple emulsion method and optimized through Minitab 16 software. The optimized microspheres were incorporated into a gel base and further characterized for physicochemical properties, release kinetics, and therapeutic activity. Antioxidant potential was analyzed using the DPPH radical scavenging assay, where IC50 values were determined for ascorbic acid (5.62 µg/mL), methanolic extract of L. sativa (6.34 µg/mL), and the microsphere-loaded gel (8.25 µg/mL). Comparative studies demonstrated that the formulated gel exhibited significant antiinflammatory activity, with performance comparable to a marketed diclofenac gel (1.16% w/w). Additionally, the extract showed dose- and time-dependent edema reduction (P<0.05) and a pronounced dose-dependent anxiolytic effect (P<0.001). Collectively, these findings highlight the therapeutic promise of L. sativa extract as a natural source of antiinflammatory, antioxidant, and anxiolytic agents, with microsphere-based gel delivery offering sustained release and enhanced clinical applicability.