Development, Characterization, and Evaluation of Novel Broad-Spectrum Antimicrobial Topical Formulations from Cymbopogon martini (Roxb.) W. Watson Essential Oil

BACKGROUND: Skin infections were the most frequently encountered of all infections and the 4th leading cause of nonfatal disease burden. Topical drugs have been used for the management of skin infections. The growing concern of drug resistance to the topical agents has warned the need for continuous development of novel drug. Essential oils are the best candidate for new drug with different mode of action and target as they are rich in chemical constituents. OBJECTIVE: To evaluate and develop safe and effective topical antimicrobial formulations from essential oil of Cymbopogon martini. Method. Essential oil was extracted using hydrodistillation aerial part C. martini and topical formulations were prepared in five different semisolid bases. In vitro antimicrobial investigations were performed on essential oil and topical formulations. Skin sensitizations of the formulations were evaluated using guinea pig maximization. RESULTS: The essential oil of C. martini has shown broad-spectrum antimicrobial potency against all tested organisms with MIC value ranging from 0.65 to 10 μg/ml. Absolute inhibitions of growth of fungi were observed against Trichophyton mentagrophytes and Trichophyton rubrum at concentrations above 1% of oil and against Microsporum canis and Trichophyton verrucosum at a concentration of 4% oil. Among topical formulations, the highest antimicrobial activity was recorded in hydrophilic ointment followed by macrogol blend ointment. The antimicrobial activity of oil was higher in fungal pathogen compared to bacteria. Gram positive bacteria were more sensitive than gram negative bacteria. Hydrophilic and macrogol blend ointment containing 5% oil did not produce any skin sensitization on guinea pigs. CONCLUSION: In conclusion, topical formulations of C. martini essential oil can be alternative topical agents with safe broad-spectrum activity for the treatment of skin disorder. Further studies should focus on shelf life study and clinical study of the product.