Evaluation of the in vitro enzyme inhibition and antioxidant activity of Clinopodium betulifolium (Boiss. & Balansa) Kuntze

Abstract

ABSTRACT Aims: Clinopodium betulifolium (Boiss. & Balansa) Kuntze is a perennial herb belonging to the Lamiaceae family. There are not many studies on C. betulifolium, except for its essential oil. In this study, Alzheimer's and cosmetic-related enzyme inhibitory activity and antioxidant activity of C. betulifolium species were evaluated. Material and methods: In this study, C. betulifolium aerial parts were extracted by maceration using 70% methanol and water. Antioxidant [DPPH quenching assay and ABTS cation decolorization, and iron chelating activity] and enzyme inhibition (acetyl-, and butyrylcholine esterase, and tyrosinase) activities of C. betulifolium extracts were evaluated using Elisa microplate reader at 2 mg/mL stock concentration. Results: C. betulifolium aqueous extract gave high antioxidant activity (IC50: 34.24±5.01 µg/mL) in the ABTS method, while its 70% methanol extract (IC50: 100.75±2.62 µg/mL) was higher than the aqueous extract (IC50: 131.83±4.70 µg/mL) in the DPPH method. C. betulifolium aqueous and 70% methanol extract have moderate antityrosinase activity. Both 70% methanol and aqueous extracts showed similar and high activity against acetylcholinesterase with the IC50 values of 73.94±2.78 µg/mL and 81.71±9.38 µg/mL, respectively. C. betulifolium 70% methanol extract (IC50: 64.08 ±1.04µg/mL) showed higher inhibitory activity than the aqueous extract (IC50: 146.6±8.27µg/mL) against butyrylcholinesterase. Conclusions: These results provide basic information for studies that will yield positive results in the development of pharmaceutical formulations or food supplements to be used in the treatment of Alzheimer's and oxidative stress-related diseases. Keywords: Clinopodium betulifolium, Anti-cholinesterase, Anti-tyrosinase, Antioxidant activity