Development, Characterization, and Evaluation of Topical Antibacterial Formulations From Achyranthes aspera

Skin diseases are a significant global health issue, particularly in developing nations. However, the efficiency of topical antibacterial treatments is diminishing due to the development of resistance. This study is aimed at developing and evaluating topical antibacterial formulations from Achyranthes aspera, a plant traditionally used for wound healing. The Kirby-Bauer method was employed to examine the antibacterial activity of hydroalcoholic extracts obtained from fresh and dried leaves of A. aspera. The fraction, which demonstrated the highest antibacterial activity, underwent further testing to determine its minimum inhibitory concentration (MIC) and was employed to formulate eight different topical formulations. These formulations were subsequently evaluated for their antibacterial effectiveness, sensory properties, pH, viscosity, spreadability, and acute dermal toxicity and underwent FTIR compatibility analysis and 3-month accelerated stability studies (40°C/75% RH). The results indicated that the 70% hydroalcoholic extracts of A. aspera were effective against common skin bacteria, particularly Staphylococcus aureus. Among the fractions tested, the chloroform fraction exhibited the largest zones of inhibition (16.50 ± 0.76 mm for S. aureus and 15.33 ± 0.33 mm for Pseudomonas aeruginosa) and an MIC of 3.125 mg/mL for both bacteria. Among the eight formulations, the basic cream demonstrated the highest antibacterial performance with a ZI of 19 ± 0.577, followed by the emulsifying ointments. FTIR analysis confirmed the absence of chemical interactions between the active fraction and formulation excipients. All formulations displayed favorable pH levels, good spreadability, homogeneity, and stability and did not cause irritation when applied to mice at a dosage of 2000 mg/kg. The accelerated stability study confirmed that the basic cream and emulsifying ointment maintained their physicochemical properties and antibacterial efficacy over 3 months. The findings suggest that A. aspera chloroform fractions are promising for developing effective topical treatments for S. aureus-related skin infections.