Formulation of topical gel containing Tagetes erecta L. floral extract and its antibacterial activity

Abstract

Tagetes erecta L. (marigold) flowers were extracted to obtain crude ethanolic extract (MGE), water insoluble extract (MGP), as well as water soluble extract (MGW). All extracts were determined of total flavonoid content and antibacterial activities against Staphylococcus aureus and Pseudomonas aeruginosa. The results suggested that MGP contained the highest amount of total flavonoids (29.48%w/w quercetin equivalent) with good activity against S. aureus (MIC 6.25 mg/mL and MBC 25.0 mg/mL). This extract was subjected to formulate the topical gels at the concentration of 1 and 2 times of MIC. The gel formulation containing 1.25%w/w MGP with the solvent mixture of propylene glycol and ethanol (1:1) showed good physical properties. Furthermore, it exhibited the most effective antibacterial activity against S. aureus by agar well diffusion method with the inhibition zone of 15.15±0.43 mm. Therefore, the extract of marigold flower could be formulated as topical gel for the treatment of skin infections.