In vitro synergistic/antagonistic antibacterial and anti-inflammatory effect of various extracts/essential oil from cones of Tetraclinis articulata (Vahl) Masters with antibiotic and anti-inflammatory agents

The aim of this work was to study for the first time the phenolic composition and synergistic/antagonistic antibacterial and anti-inflammatory effect between various extracts/essential oil from cones of Tetraclinis articulata (Vahl) Masters and antibiotic/anti-inflammatory agents. 12 components were identified in essential oil, which are mostly oxygenated monoterpenes (94.47%). HPLC-DAD analysis showed that the tannic acid (0.45 +/- 0.038 - 1.85 +/- 0.18 mu g/g) and gallic acid (0.72 +/- 0.044 - 1.98 +/- 0.20 mu g/g) are present in all extracts. The ethanol 70% extract was the most effective against the tested bacteria and exhibits the highest anti-inflammatory activity. Even, the combination of antibiotic with this extract was more effective, showing synergism or partial synergism effect in 100% against the tested bacteria. While, the methanol 100% extract was less effective, showing antagonism effect in 100% against the tested bacteria. In the same way, the combination of the specify inhibitors of lipooxygenase and xanthine oxidase (NDGA/allopurinol) with ethanol 70% extract was more effective, showing synergism inhibition effect against both enzymes. According to these results, the ethanol 70% extract may represent a potential valuable source of bioactive and anti-inflammatory agents and an alternative for the treatment of infectious diseases caused by the tested bacteria and the inflammation where the lipooxygenase and xanthine oxidase are involved. Even, this extract can be used in combination with the antibiotics and anti-inflammatory agents to give synergism effect, which allow us to reduce their effective antimicrobial and anti-inflammatory dose and thereby reducing their undesirable problems and side effects. (C) 2014 Elsevier B.V. All rights reserved.