Anti-bacterial activity of novel gel formulations prepared with seed extracts of Coriandrum sativum L. and Nigella sativa L. against Staphylococcus aureus

Abstract

Acne vulgaris is a chronic dermatologic condition with a complex pathogenesis which involves inflammation of pilosebaceous units (hair follicles and their accompanying sebaceous gland). It is generally characterized by the presence of Propionibacterium acnes, an anaerobic bacterium that mostly resides in the pilosebaceous follicles of the skin and Staphylococcus aureus infection, inflammation, seborrhea and follicular hyperproliferation. Spices like seeds of Coriandrum sativum L. and Nigella sativa L. are known to produce phytochemicals that exhibit antioxidant action and anti-bacterial effect and consequently may have propitious activity against inflammatory acne caused by S. aureus. The objective of this study was to determine the MIC (minimum inhibition concentration) and MBC (minimum bactericidal concentration) values of the face gels against S. aureus. Six gel bases were prepared by using carbapol 940, phenoxy ethanol, EDTA, rose water, poly ethelene glycol and triethanolamine. The seed extracts of C. sativum and N. sativa were combined into the gel bases at predetermined strengths. The MIC and MBC values were determined by broth micro-dilution and direct plate on agar methods respectively. All six face gels combined with the seed extracts of C. sativum and N. sativa exhibited very potent anti-bacterial effect against S. aureus. The MIC values of the face gel series were observed as 62.5-250 μg/mL and MBC values were determined as 125-500 μg/mL. The observations demonstrate that all six face gels exhibited potent anti-bacterial effect against S. aureus and this effect of the face gels becomes greater when the proportion of the seed extract in the formulation increases.