In vitro antioxidant and cholinesterase inhibitory activities of methanolic fruit extract of 1

47 48 Background: Alzheimer’s disease (AD) is a progressive neurodegenerative disorder clinically 49 characterized by loss of memory and cognition. Cholinergic deficit and oxidative stress have 50 been implicated in the pathogenesis of AD. Therefore, inhibition of acetylcholinesterase and 51 oxidation are the two promising strategies in the development of drug for AD. Phyllanthus 52 acidus, belonging to the family Euphorbiaceae, is a tree and has been used in traditional 53 medicine to treat several pain, inflammatory and oxidative stress related disorders such as 54 rheumatism, bronchitis, asthma, respiratory disorder, also important to promote intellect and 55 enhance memory, thus supporting its possible anti-Alzheimer’s properties. In this study, P. 56 acidus was evaluated for its cholinesterase inhibitory and antioxidant activities. 57 58 Methods: In this study, we evaluated the antioxidant potential and neuroprotective activity of P. 59 acidus by assessing total phenol content (FCR assay), total flavonoid content, total antioxidant 60 capacity, Fereducing power capacity, DPPH (2, 2-diphenyl-1-picrylhydrazyl) and hydroxyl 61 radical scavenging capacity, lipid peroxidation inhibition activity & metal chelating activity. In 62 addition acetylcholinestrase (AChE) and butyrylcholinestrase (BChE) inhibitory activities were 63 performed using Ellman’s method. 64 65 Results: Total phenolic content and total flavonoid content of the extract were 116.98 mg of 66 gallic acid equivalent and 168.24 mg of quercetin equivalent per gm of dried extract. The 67 methanolic extract of P. acidus (MEPA) showed considerable total antioxidant activity and 68 reducing capacity. In DPPH scavenging assay and hydroxyl radical scavenging assay, the MEPA 69 showed 84.33% and 77.21% scavenging having IC50 of 15.62 and 59.74 μg/ml respectively. In 70 lipid peroxidation inhibition activity MEPA showed moderate inhibition of peroxidation at all 71 concentrations with IC50 value of 471.63μg/ml and exhibited metal chelating activity with IC50 72 value 308.67μg/ml.The MEPA exhibited inhibition of rat brain acetylcholinesterase and human 73 blood butyrylcholinesterase in a dose dependent manner and the IC50 value was found to be 74 1009.87μg/ml and 449.51μg/ml respectively. 75 76 Conclusion: These results of the present study reveal that MEPA has considerable amount of 77 antioxidant activity as well as anti-acetylcholinesterase and anti-butyrylcholinesterase activity 78 which suggest its effectiveness against Alzheimer's disease and other neurodegenerative 79 disorders. 80 81