EFFECT OF ALKALOID EXTRACTS OF WATER BITTER LEAF (STRUCHIUM SPARGANOPHORA) AND SCENT LEAF (OCIMUM GRATISSIMUM) ON MANGANESE INDUCED NEUROTOXICITY IN DROSOPHILA MELANOGASTER

Abstract

Manganese (Mn) is an essential trace element necessary for physiological processes that support development, growth and neuronal function. Secondary to elevated exposure or decreased excretion, Mn accumulates in the basal ganglia region of the brain and may cause a parkinsonian-like syndrome, referred to as manganism. Therefore, this study sought to determine the effect of alkaloid extracts from Scent Leaf (Ocimum gratissimum) and Water Bitter leaf (Struchium sparganophora) on behavioural/survival and biochemical changes in Manganese-induced neurotoxicity in fruit flies (Drosophila melanogaster). Alkaloid-rich extracts were prepared from freshly harvested Scent leaf and Water bitter leaf and their antioxidants properties as typified by [2,2-diphenyl-1- picrylhydrazyl radical (DPPH*), 2,2- azinobis (3-ethylbenzothiazoline-6-sulfonate radical (ABTS*),Nitric Oxide (NO) and Hydroxyl Oxide (OH) radical scavenging abilities as well as Fe-chelation and ferric reducing antioxidant property (FRAP) were determined. and endogenous antioxidant enzyme such as catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferase (GST) were determined. Also, the effects of the alkaloid extracts on acetylcholinesterase (AChE) activity were assessed in vitro. The tolerance/ effective safe dose of the extracts was also determined. Dopamine contents of the flies were quantified using high performance liquid chromatography (HPLC). The extracts were able to reduce malondialdehyde (MDA) production. The activity of Acetylcholinesterase (AChE), Butyrylcholinesterase (BChE), Monoamine Oxidase (MAO), Catalase and Glutathione-S-transferase (GST), were all assayed. The antioxidant ability of the extracts and their inhibitory effect on some key enzymes and biomolecules linked to neurodegeneration pathology is an indication of their potential as nutraceuticals/functional food in the management of ND.