Food as Medicine: Acetylcholinesterase Inhibitory and Toxicity of <em>Carica Papaya</em> Seeds

Abstract

Food is a great source of medicine because it supports life existence and its absence can lead to death. Carica papaya, a fruit which is popular worldwide, possesses a number of medicinal attributes. The ripe and matured unripe seeds were investigated for their acetycholinesterase (AChE) inhibitory activity, toxicity and antioxidant activities. AChE inhibitory activities of 70% cold ethanolic extract of the pawpaw seeds were assessed. Partitioned fractions using petroleum spirit and ethyl acetate and the vacuum liquid chromatographed portions of the ethyl acetate fraction were all evaluated in-vitro at 500μg/ml concentration using modified Ellman method. The Brine shrimp lethality test of the extract was used to determine the toxicity profile and DPPH to determine the antioxidant property. The results showed that the crude extract gave 41.16% AChE inhibition. Purification enhanced the activity. The ethyl acetate fraction on analysis produced 60.29% activity and the semi-pure compound from the VLC analysis resulted in 65.25% activity whilst Eserine gave 74.78% inhibition.. The autobiographic antioxidant TLC analysis using DPPH as detection agent showed the unripe matured seeds to possess antioxidant activity. The study is reporting for the first time the acetylcholinesterase inhibitory activity of C papaya. Based on the results obtained, it may be deduced that the fruit can be eaten to manage Alzheimer’s disease.