Assessments of anticholinergic, antidiabetic, antioxidant activities and phenolic content of Stachys annua

Abstract

Some biochemical properties including phenolic content, anticholinergic, antidiabetic, and antioxidant activities of Stachys annua were determined in this study. The methanol extract of Stachys annua (MESA) and the water extract of Stachys annua (WESA) were prepared and used for all biochemical analyses. Antioxidant capacities of MESA and WESA were evaluated by six different in vitro bioanalytical methods including three reducing antioxidant methods and three radical scavenging antioxidant methods. Also, enzyme inhibition effect of Stachys annua against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase, and α-glycosidase enzymes were determined separately. According to the results, both extracts showed high inhibition effects against α-amylase and α-glycosidase enzymes, whereas they showed low inhibition effects against AChE and BChE enzymes. The IC50 values of MESA and WESA against AChE (119.8 ± 2.4 μg/mL and 150.1 ± 3.0 μg/mL), BChE (192.1 ± 3.8 μg/mL and 186.7 ± 3.7 μg/mL), α-glycosidase (25.7 ± 0.5 μg/mL and 18.7 ± 0.4 μg/mL), and α-amylase (43.3 ± 0.9 μg/mL and 11.4 ± 0.2 μg/mL) were determined, respectively. Another goal of the study was to evaluate the phenolic compositions of Stachys annua by liquid chromatography and tandem mass spectrometry (LC-MS/MS). Quercetagetin-3,6-dimethylether (178.6 ± 33.5 μg/g), chlorogenic acid (118.2 ± 16.4 μg/g), and fumaric acid (102.5 ± 7.1 μg/g) were identified as major compounds in MESA. On the other hand, fumaric acid (309.5 ± 21.5 μg/g), apigenin (144.6 ± 11.7 μg/g), and chlorogenic acid (78.1 ± 10.8 μg/g) were identified as major compounds in WESA. This study will be a scientific base for further studies about Stachys annua for food or medicinal utilization.