ABSTRACT

This study was cauied out to determine the phytochemical composition of three common medicinal plants (Psidium guajava, Baphia nitida, Icacina trichanta Oliv.} and their effect on cholinergic receptors (ex-vivo). The plant samples were acquired fiom Amawom in Ikwuano LGA of Abia state. The plant (leaves) samples were air dried under room temperature on a laboratory bench and milled using manual grinder. The coarse powdered material was weighed with an electronic balance. Each of the powdered plant samples (200g) was extracted by cold maceration in 80% methanol for 48 hours with intenmittent shaking every 3 hours to ensure constant contact with the solvent. Afterwards they were filtered with Whatmann No.l filter paper and their filtrates were evaporated using the rotary evaporator and hot air oven to obtain the crude extract. The phytochemical screening ofthese plant extracts revealed the presence ofsome ofthe major classes of phytochemials which include; tannins, flavonoids, saponins, terpenes and glycosides. A rabbit was starved for 48hours after which it was killed and its jejunum was extracted and suspended in a thyroid solution. The effects of different concentrations of the extracts on cholinergic receptors were analyzed. The study revealed that varying concentrations of these extracts possess anticholinergic effects which in most cases are time and concentration dependent. Baphia nitida has a short-lived activity at lower concentration but at higher concentration its activity is sustained. The activity of Icacina trichanta Oliv. increases with increase in concentration. Psidium guajava has a significant activity at all concentration but its activity increases with time.