Evaluation of enzyme inhibitory and antioxidant activity of some Lamiaceae plants

Lamiaceae is one of the most widespread families in Turkey. The aim of this study was to determine antialzheimer, antidiabetic, antioxidant and antiobesity activities of ethanol extracts of Larnium purpureurm var. purpureum, Origanum onites, Salvia sclarea, S. virgata and Thymus zygioides var. hicaonius. Acetylcholinesterase, butyrylcholinesterase, alpha-amylase, alpha-glucosidase, and pancreatic lipase inhibitory activities were tested for the determination of the activity of these extracts. Furthermore, total antioxidant, ferric-reducing antioxidant power, metal-chelating and N,N-dimethyl-p-phenylendiamine radical scavenging assays were utilized to screen antioxidant activity. Total phenolic content of the extracts were also calculated. Among the tested extracts, T. zygioides var. lycaonius aerial part extract (85.28 +/- 0.89 %) showed the highest inhibitory activity against alpha-glucosidase. The inhibitory activities of all extracts against alpha-amylase were lower than 50 %. S. sclarea leaf extract indicated remarkable butyrylcholinesterase inhibition (51.76 +/- 1.04 %), but all of the plant extracts were inactive against acetylcholinesterase. The Salvia species showed the highest total antioxidant activity. S. sclarea flower (1.34 +/- 0.08) and leaf (1.34 +/- 0.08) extracts showed the highest ferric-reducing antioxidant power activities. Our findings indicated that O. onites, S. sclarea, S. virgata, and T. zygioides var. lycaotrius extracts showed valuable inhibitory activity and emerged as the sources of possible alpha-glucosidase inhibitors for future studies.