Formulation and Evaluation of Antimicrobial Cream of Lavandula bipinnata, Nigella sativa, and Cynodon dactylon

Abstract

The present study aimed to formulate and evaluate an antimicrobial cream utilizing plant extracts of Lavandula bipinnata, Nigella sativa, and Cynodon dactylon. The formulation process involved thorough phytochemical screening, chromatographic profiling (TLC and HPLC), and FTIR spectroscopy to confirm the presence of key bioactive constituents, including flavonoids, phenolics, terpenoids, and alkaloids. Extraction yields were notably high in the aqueous extracts—12.3% (L. bipinnata), 10.2% (N. sativa), and 11.5% (C. dactylon)—indicating a rich content of hydrophilic phytochemicals. The cream formulations (F1-F5) were evaluated for pH, viscosity, spreadability, and thermal stability, with the polyherbal formulation (F5) showing optimal pH (6.10), higher viscosity (6175 cps), and excellent spreadability (95%). Antimicrobial activity was assessed using the agar well diffusion method against Escherichia coli and Salmonella spp., revealing that F5 exhibited the highest activity against E. coli (zone of inhibition: 7 mm), while minimal activity was observed against Salmonella spp. (1 mm). Compared to standard antibiotics (streptomycin: 7–6 mm; tetracycline: 9–10 mm), the polyherbal cream demonstrated promising potential against E. coli. These findings suggest that the synergistic combination of these plant extracts in a topical formulation holds promise as a natural alternative for the treatment of skin infections caused by E. coli, though further optimization is needed for broader-spectrum efficacy.