Lawsonia inermis flower aqueous extract expressed better anti-alpha-glucosidase and anti-acetylcholinesterase activity and their molecular dynamics

Abstract

Lawsonia inermis (henna) has been used in traditional medicine throughout the world and biological property of its flower has been least explored. In the present study, the phytochemical characterization and biological activity (in vitro radical scavenging activity, anti-alpha glucosidase and anti-acetylcholinesterase) of aqueous extract prepared from henna flower (HFAE) was carried out by both Qualitative and quantitative phytochemical analysis and Fourier-transform infrared spectroscopy revealed the functional group of the phytoconstituents such as phenolics, flavonoids, saponin, tannins and glycosides. The phytochemicals present in HFAE was preliminary identified by liquid chromatography/electrospray ionization tandem mass spectrometry. The HFAE showed potent in vitro antioxidant activity and the HFAE inhibited mammalian α-glucosidase (IC₅₀ = 129.1 ± 5.3 µg/ml; Ki = 38.92 µg/ml) and acetylcholinesterase (AChE; IC₅₀ = 137.77 ± 3.5 µg/ml; Ki = 35.71 µg/ml) activity by competitive manner. In silico molecular docking analysis revealed the interaction of active constituents identified in HFAE with human α-glucosidase and AChE. Molecular dynamics simulation for 100 ns showed the stable binding of top two ligand/enzyme complexes with lowest binding energy such as 1,2,3,6-Tetrakis-O-galloyl-beta-D-glucose (TGBG)/human α-glucosidase, Kaempferol 3-glucoside-7-rhamnoside (KGR)/α-glucosidase, agrimonolide 6-O-β-D-glucopyranoside (AMLG)/human AChE and KGR/AChE. Through MM/GBSA analysis, the binding energy for TGBG/human α-glucosidase, KGR/α-glucosidase, AMLG/human AChE and KGR/AChE was found to be −46.3216, −28.5772, −45.0077 and −47.0956 kcal/mol, respectively. Altogether, HFAE showed an excellent antioxidant, anti-alpha glucosidase and anti-AChE activity under in vitro. This study suggest HFAE with remarkable biological activities could be further explored for therapeutics against type 2 diabetes and diabetes-associated cognitive decline.

Communicated by Ramaswamy H. Sarma

Key words:

• Lawsonia inermis flower
• alpha-glucosidase
• acetylcholinesterase
• molecular docking and dynamics

Acknowledgment

The authors acknowledged DST-FIST (SR/FIST/LSI-673/2016) released a major grant to the Biotechnology Department to strengthen the instrumentation facility. The authors would like to thank the Computer Centre, Periyar University, Salem provided the High-Performance Cluster (HPC) computer facility funded by RUSA for the computational works.

Author contribution

Shahanaj Ismail: Conceptualization, Investigation, Statistics, Auto dock, Writing—original draft. Natarajan Devarajan: Writing- Reviewing and Editing, Supervision and Project administration. Jaganathan Ramakrishnan and Kumaradhas Poomani- MD simulation, MM/GBSA calculation, Reviewing and Editing.

Disclosure statement

All the authors declare that they have no conflict of interest that could have appeared to influence the work reported in this article.