In vitro antidiabetic, antioxidant activities and chemical composition of Ajuga parviflora Benth. shoot

Introduction: Ajuga parviflora Benth. (Lamiaceae) is an herbaceous plant that possesses ethnomedicinal values and is well known for its folkloric management of diabetes. This study was aimed to provide an experimental justification for its traditional antidiabetic use. Methods: Hydroalcoholic extract of A. parviflora shoot was quantified for its total phenolic content (TPC), total flavonoid content (TFC), and total tannin content (TTC). Gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectrophotometer (FTIR) spectroscopy were also used for their chemical nature. Additionally, the extract was evaluated for its inhibitory potential against key enzymes linked with hyperglycemia by in vitro means. Subsequently, for estimation of the antioxidant capacities 2,2-diphenyl-2-picrylhydrazyl radical (DPPH), 2,2’-azino-bis (3-ethylbenzothiazoline-6- sulfonic acid) radical (ABTS), and hydrogen peroxide (H_2O_2) scavenging activities were determined. Results: GC-MS analysis revealed numerous biologically active phytoconstituents including brassicasterol, phytol, and palmitic acid. The presence of different active functional groups such as alcohol, nitrile, amine, alkyl halide, alkene, and alkane was confirmed by FTIR analysis. The extract showed a significant (P≤ 0.05) dose-dependent inhibition for α- amylase enzyme (132.38±1.18 μg/mL), α-glucosidase enzyme (22.66±0.11 μg/mL), DPPH radical (103.03±1.59 μg/mL), ABTS radical (140.10±3.40 μg/mL) and H_2O_2 radical (298.26±4.37 μg/mL). TPC, TFC, and TTC were found 64.06±0.35 mg/g of the gallic acid equivalent (GAE), 45.27±0.58 mg/g of the rutin equivalent (RE), and 127.42±1.82 mg/g of the tannic acid equivalent (TAE), respectively. Conclusion: A. parviflora extract showed significant antioxidant and antidiabetic potentials. Thus, this plant might be served as a novel approach for discovering new and effective drug molecules against hyperglycemia.