Chemical composition, antioxidant and antimicrobial activity of Thymus praecox supercritical extracts

Abstract

The chemical composition, antimicrobial and antioxidant activity of Thymus praecox extracts obtained by fractional supercritical fluid extraction (SFE) with carbon dioxide were investigated. Properties of supercritical extracts and extracts obtained by Soxhiet extraction were compared. The chemical composition of extracts was determined using GC-FID and GC-MS analytical methods. The antimicrobial activity of extracts was evaluated against 16 pathogenic microorganisms using microdilution method. Antioxidant potential of extracts to neutralize DPPH radicals was also investigated. Investigated supercritical extracts showed better antimicrobial activity than commercial antibiotics (streptomycin and ampicillin) and commercial fungicides (bifonazol and ketoconazole) against all tested strains. For bacteria MIC and MBC were 38-200 mu g/m1 and 75-300 mu g/ml, respectively, while for fungi MIC and MFC were 17-150 mu g/ml and 35-300 mu g/ml, respectively.