Investigation of acetylcholinesterase, butyrylcholinesterase, α-glucosidase, α-amylase, and tyrosinase inhibition and antioxidant activity of methanol and water extracts from aerial parts of Phlomis lycia D. DON

Abstract

Background: Natural antioxidants in the plant kingdom play an essential role in reducing the risk of various chronic diseases and maintaining a healthy life. In addition, acetylcholinesterase, butyrylcholinesterase, α-glucosidase, α-amylase, and tyrosinase are involved in the occurrence and pathology of some as Alzheimer’s and diabetes, have become an important strategic target in the effective treatment of these diseases. Phlomis lycia D. DON is traditionally used as an appetizer, stimulant, carminative, tonic, and against stomach pain and dyspeptic complaints. There is limited knowledge on this species except for preliminary studies such as botanical and phytochemicals and biological properties. The aerial parts of this plant contained phenolic compounds, such as lignan, phenylethanoid, and iridoid derivatives which can be responsible for the potential biological effects. Therefore, the present study was aimed to investigate the antioxidant and enzyme inhibition activity of the methanol and water extracts obtained from aerial parts of P. lycia in the flora of Turkey. Material and Methods: Antioxidant potentials were determined spectrophotometrically by DPPH and ABTS radical scavenging, iron chelating, and β-Carotene/linoleic acid emulsion method. We evaluated the inhibitory activities of methanol and water extracts of P. lycia against various enzymes (acetylcholinesterase, butyrylcholinesterase, α-glucosidase, α-amylase, and tyrosinase) by using 96-well plate methods. Results: According to the results, the methanol extract was more active than water extract in terms of antioxidant activity. On the other hand, although the methanol and water extracts were observed to demonstrate similar enzyme inhibitory activity, the water extract exhibited more inhibition activity on α-glucosidase. Conclusions: Our results suggested that Phlomis lycia could potentially be used for the isolation of potent antioxidants from the methanol extract. To the best of our knowledge, this study represents the first time that Phlomis lycia was reported in the literature with glucosidase inhibition activity.