Acetylcholinesterase and Butyrylcholinesterase Enzyme Inhibitory Effect of Alangium salviifolium (L. f.) Wang pericarp Extracts with Their Phytochemical and Antioxidant Values

Aims: Alangium salviifolium (L. f.) Wang is a medicinal plant of the Alanginaceae family which was used as a traditional medicine to cure or prevent a variety of ailments. The aim of the study was to investigate the anticholinesterase effects and compare the phytochemical and antioxidant values of ethanol, dichloromethane, chloroform and aqueous extracts of A. salviifolium pericarp.

Place and Duration of Study: The study was done in Department of Pharmacy, Comilla University, Comilla, Bangladesh and Southeast University, Dhaka, Bangladesh, between January 2015 to December 2016.

Materials and Methods: The pericarp of A. salviifolium was extracted with different solvents. Ellman's assay was applied to investigate acetylcholinesterase and butyrylcholinesterase enzyme inhibitory effect. Phytochemical screening has been done by using qualitative methods whereas total phenol content, total flavonoid content and total flavonol content were determined by Folin-Ciocalteau reagent, aluminum trichloride and sodium acetate solution methods, respectively. Antioxidant activities were assessed by DPPH radical scavenging, FRAP and TAC assay.

Results: Donepezil, a standard drug, showed maximum inhibitory effect of AChE (IC50: 6.30±1.23 μg/mL) and BChE (IC50: 8.70±0.21 μg/mL). EASP followed by AASP had potent inhibitory effects while CASP and DASP had mild inhibitory effects of the enzymes. Preliminary phytochemical screening exposed the presence of valuable phytochemicals with significantly (P*<0.05, P**<0.01, P***<0.001) different content of TPC, TFC and TFlC. EASP, among the extracts, had shown the highest TPC (524.28±7.14 mg/g gallic acid), followed by TFC (231.90±14.86 mg/g quercetin) and TFlC (139.44±5.55 mg/g quercetin). In fact, maximum antioxidant potential, FRAP (EC50: 50.33±4.93 μg/mL) and TAC (352.40±19.51 mg/g ascorbic acid) was found in the EASP.

Conclusion: This research has revealed that different pericarp extracts of the A. salviifolium have moderate to potent antioxidant and enzyme inhibitory effects and further analysis may find potential candidate for healing Alzheimer’s disease.