J. M. Makinde

Studies on the anti-inflammatory, antipyretic and analgesic properties of Alstonia boonei stem bark

The methanol extract of the stem bark of Alstonia boonei was investigated for anti-inflammatory property. The analgesic and antipyretic properties of the extract was also evaluated. The extract caused a significant (P<0.05) inhibition of the carrageenan-induced paw oedema, cotton pellet granuloma, and exhibited an anti-arthritic activity in rats. Vascular permeability induced by acetic acid in the peritoneum of mice was also inhibited. The extract also produced marked analgesic activity by reduction of writhings induced by acetic acid, as well as the early and late phases of paw licking in mice. A significant (P<0.05) reduction in hyperpyrexia in mice was also produced by the extract. This study has established anti-inflammatory, analgesic and antipyretic activities of the stem bark of A. boonei.

Effects of the aqueous extract of Bridelia ferruginea stem bark on carrageenan-induced oedema and granuloma tissue formation in rats and mice.

The anti-inflammatory activity of the aqueous extract of the stem bark of Bridelia ferruginea was evaluated using carrageenan-induced paw oedema in rats and mice, and the cotton pellet granuloma method. The extract at doses ranging from 10 to 80 mg/kg p.o. significantly inhibited the carrageenan-induced rat paw oedema, with an ID50 value of 36 mg/kg. However, a low activity was produced in the mouse paw oedema. The extract also suppressed the granulomatous tissue formation of chronic inflammation. B. ferruginea therefore proved to be effective in both the acute and chronic phases of the inflammatory process.

Pharmacological studies on the leaf of Psidium guajava

The methanol extract of the leaves of Psidium guajava was found to inhibit paw oedema induced by carrageenan in rats and pain induced by acetic acid in mice, and exhibited an antipyretic effect. Oral administration of the extract reduced intestinal transit time and prevented castor oil-induced diarrhoea in mice. A CNS depressant activity was exhibited by the extract by potentiating the phenobarbitone sleeping time in mice.

Studies on the anti-inflammatory and related pharmacological properties of the aqueous extract of Bridelia ferruginea stem bark

The anti-inflammatory profile of the aqueous extract of Bridelia ferruginea stem bark was investigated using both in vivo and in vitro models. The extract exhibited strong topical anti-inflammatory effect shown as inhibition of croton oil-induced ear oedema in mice, and reduced hind-paw swelling and growth retardation in the adjuvant-induced arthritis model in rats, following oral administration at 10, 20, 40 or 80 mg/kg. The extract (10-80 mg/kg, p.o.) caused an inhibition of increase in vascular permeability in both cyclophosphamide-induced haemorrhagic cystitis and acetic acid-induced vascular permeability in rats and mice, respectively. B. ferruginea produced stabilization of erythrocytes exposed to heat and stress-induced lysis. Antipyretic and analgesic properties of the extract were also observed.

Evaluation of the Anti-diabetic Property of Morinda lucida Leaves in Streptozotocin-diabetic Rats

The hypoglycaemic and anti‐hyperglycaemic activities of a methanol extract of Morinda lucida Benth. (Rubiaceae) leaves were studied in normal and streptozotocin‐diabetic rats.

Antiplasmodial and antipyretic screening of Mangifera indica extract

The stem bark extract of Mangifera indica was evaluated for antiplasmodial activity against Plasmodium yoelii nigeriensis. The extract was also screened for antipyretic activity in mice. The extract exhibited a schizontocidal effect during early infection, and also demonstrated repository activity. A reduction in yeast‐induced hyperpyrexia was also produced by the extract.

Cathartic effect of the leaf extract of Vernonia amygdalina

A methanol extract of Vernonia amygdalina leaves was evaluated for cathartic effect. The extract exhibited a significant promotion of intestinal motility on charcoal meal test in mice. Frequency of defecation and of faeces were markedly increased following administration of the extract which also promoted gastric emptying in rats. Preliminary studies on the isolated rat fundus strip showed a contractile effect, which was blocked by atropine.

Anti-inflammatory studies on Adenanthera pavonina seed extract.

A methanol extract of the seeds of Adenanthera pavonina was evaluated for pharmacological effects in animal models. The extract (50–200 mg/kg) produced statistically significant (P < 0.05) inhibition of the carrageenan-induced paw oedema in the rat, as well as the acetic-acid-induced vascular permeability in mice. At doses of 100 and 200 mg/kg, pleurisy induced with carrageenan was also inhibited. The extract (50–200 mg/kg) exhibited a dose-dependent and significant (P < 0.05) analgesic activity in the acetic-induced writhing in mice. In addition, both early and late phases of the formalin-induced paw licking in mice was inhibited by the extract. Acute toxicity studies revealed that the extract produced reduced motor activity. The LD50 value of the extract was found to be 1.36 g/kg. This study demonstrated the anti-inflammatory and analgesic effects of A. pavonina extract.

A preliminary study on the hypotensive activity of Persea americana leaf extracts in anaesthetized normotensive rats

Abstract The effect of the constituents of the leaves of Persea americana on arterial blood pressure was investigated in anaesthetized normotensive rats. The intravenous administration induced a marked fall in mean arterial blood pressure which lasted 2–3 min. The short duration of action may be due to rapid metabolism.

Antimalarial Active Principles of Spathodea campanulata Stem Bark

Antimalarial principles of Spathodea campanulata stem bark extract were isolated and characterized. The antimalarial principles in the stem bark were 3β‐hydroxyurs‐12‐en‐28‐oic acid (ursolic acid) and two of its derivatives; 3β‐hydroxyurs‐12,19‐dien‐28‐oic acid (tomentosolic acid) and 3β,20β‐dihydroxyurs‐12‐en‐28 oic acid. This is the first report of the isolation of ursolic acid and its derivatives as antimalarial compounds