Investigation of the effects of Lavandula officinalis Mill., Melissa officinalis L., Mentha piperita L., Salvia officinalis L. and Scutellaria orientalis L. species belonging to Lamiaceae family on anti-inflammatory pathway enzymes Lipoxygenase (LOX) and Cyclooxygenase (COX)

In this study, the effects on the activities of LOX and COX enzymes, which have an important place in the inflammation pathway, of Mentha piperita L., Salvia officinalis L., Lavandula officinalis Mill., Scutellaria orientalis L. and Melissa officinalis L. plants selected from the Lamiaceae family were determined. They have been examined in terms of being an alternative to inhibitor drugs which have side effects that are found in excess. In this context, the DPPH+ radical scavenging effects of the extracts were investigated and their EC50 values were found as 32,03±13,52; 38,35±12,66; 108,70±8,12; 65,88±12,11 and 25,75±13,41 µg/mL, respectively. The EC50 value (±SEM) of quercetin used as a control was found as 2,92±8,54 µg/mL. There was a statistically significant difference between the radical scavenging effects of the extracts compared to the control (p<0.05). When the time dependent scavenging capacities of DPPH+ radicals were examined, it was found that reliant on the extracts, time and concentration the effects were varied.. In addition, the total antioxidant capacities of the extracts were examined by the TAC method and the extract with the highest antioxidant capacity was M. piperita L. (50 µg/mL extract, 726.62±0.02 nmol/µL Trolox equivalent value). The IC50 values of (IC50±SEM) extracts on COX-2 enzyme activity was calculated as 69,98±13,70, 26,44±17,68; 6,23±13,25; 30,43±12,32 and 16,65±9,09 µg/mL, respectively. IC50 values of (IC50±SEM) of extracts on 12/15-LOX enzyme activity was found as 14,98±9,23; 42,54±37,70; 329,48±44.77; 96,63±55,70 and 35,73±16,75 µg/mL, respectively. Analysis of crude S.officinalis L. and L.officinalis Mill. Extracts as inhibitors and their behavior on COX-2 enzyme determined that the extracts exhibited competitive inhibitory effect. When the 12/15-LOX enzyme with M. piperita L. and S. officinalis L. were examined, the extracts were found to display non-competitive inhibitory properties. Our combined results lead us to consider that the extracts have potential use as anti-inflammatory agents.