Evaluation of lyophilized royal jelly and garlic extract emulgels using a murine model infected with methicillin-resistant Staphylococcus aureus

The limited therapeutic options associated with methicillin-resistant Staphylococcus aureus (MRSA) necessitate search for innovative strategies particularly, use of natural extracts such as lyophilized royal jelly (LRJ) and garlic extract (GE). Therefore, out study aimed to formulate emulgels containing different concentrations of both LRJ and GE and to evaluate their activities using a murine model infected with MRSA clinical isolate. Four plain emulgel formulas were prepared by mixing stearic acid/yellow soft paraffin-based O/W emulsion formulae based on Carbopol 940, Na alginate, Na carboxymethylcellulose or Hydroxypropyl methyl cellulose E4. Sodium alginate-based emulgel was selected for preparation of four medicated emulgel formulations combining LRJ and GE at four different concentrations. The selected medicated emulgels were used for the in vivo studies. The emulgel formulated with Na alginate and HPMC (MF(3)) exhibited optimum smooth homogeneous consistency, neutral pH, acceptable viscosity, spreadability, extrudability values and best storage stability properties. In vivo results revealed that, the wounds infected with MRSA isolate in rates were wet (oozing) and showed pus formation when compared to injured uninfected wounds. MF(3) formula containing 4% LRJ and 50% GE showed the maximum wound healing properties, both in the apparent physical wound healing measurements and in the histopathological examination. In conclusion, the medicated emulgel formulation (MF(3)) prepared with Na alginate was found optimum for topical application. MF(3) formula containing 4% LRJ and 50% GE has shown the highest in vivo wound healing capacities. Further clinical studies should be conducted to prove both its safety and efficacy and the potential use in human.