Antidiabetic activity of aqueous and methanol extract and fractions of Gongronema latifolium (Asclepidaceae) leaves in Alloxan Diabetic Rats.

Rural dwellers in Nigeria often resort to herbal remedy and dietary control in the treatment of diabetes mellitus (DM). This work was undertaken to provide the rationale for the use of the leaves of Gogronema latifolium as a traditional antidiabetic agent. Methanol extract (ME) of the leaves of G. latifolium was prepared by soxhlet extraction while the aqueous extract (AE) was prepared by cold maceration. The methanol extract was separated into fractions by column chromatography to yield methanol fraction (MF), n-hexane fraction (HF) and chloroform fraction (CF).The extract and the fractions were evaluated for antidiabetic effect in alloxan-induced diabetes in rats. The blood sugar levels were assayed as indices of diabetes. The phytochemical analyses of the extracts and fractions as well as the LD50 of the ME were determined. The results indicated that intraperitoneal injection of AE, ME, CF, HF, and MF, (200-800 mg/kg/day) exhibited a significant (P<0.05) anti-diabetic effect by ameliorating alloxan-induced increase in blood sugar. Antidiabetic potency of the extracts and fractions was in the order; MF> ME> AE>HF>CF. Phytochemical analysis of the extracts and fractions indicated high concentration of proteins, flavonoids, saponins, alkaloids, terpenoids, and steroids while tannins, reducing sugar and acidic compounds were absent. The LD50 of the methanol extract was calculated to be 900mg/kg. The results of this study lead credence to the use of G. latifolium in the management of diabetes mellitus.

Analgesic activity of leaf extracts of Culcasia scandens P. Beauv.

Analgesic activity of methanol leaf extract of C. scandens obtained by column chromatography and its graded solvent fractions, was evaluated in mice using acetic acid-induced abdominal writhing and formalin-induced paw licking. The extract and fractions significantly inhibited abdominal writhing and two phases of formalin-induced paw licking in mice, indicating that antinociceptive activity may involve inhibition of pain by peripheral and central mechanisms.

Anti-inflammatory activity of extracts of root bark of securidaca longipedunculata Fres (Polygalaceae)

The effect of extract and fractions of the root bark of Securidaca longipedunculata Fres (Polygalaceae) on acute inflammation was evaluated. Solvent extraction yielded the crude methanol extract (ME) while solvent-guided extraction yielded a petroleum ether fraction (PF) and methanol fraction (MF). The extract and fractions inhibited topical edema induced by xylene in the mouse ear. In the systemic edema of the rat paw; the methanol extract (ME) and methanol fraction (MF) significantly (P0.05) suppressed the development of paw edema induced by egg albumin in rats while the petroleum ether fraction (PF) was devoid of such activity. Ulcerogenic assay in rats indicated that the extract and fractions exhibited varying degrees of gastric irritation in rats in the order of magnitude: MF PF ME. Phytochemical tests showed that ME and MF tested positive for carbohydrates; reducing sugars; glycosides; flavonoids; terpenoids; sterols and saponins while PF gave positive reaction for resins only. Acute toxicity test for ME in mice established an i.p and p.o LD50 of 11 and 282 mg/kg respectively

Effect of methanolic leaf extract of Cissampelos mucronata A. Rich against indomethacin induced ulcer in rats.

Five fractions (F1-F5) isolated from the methanolic leaf extract of Cissampelos mucronata A. Rich were investigated for antiulcer activity. At the dose of 450 mg/kg, they showed varying degree of protection against ulcer induced by indomethacin; the order of protection being F1>F4>F5>F2>F3. The antiulcer potency of F1 and F2 is comparable with that of cimetidine (100 mg/kg, i.p.). Inhibition of gastric mucosal damage may partly contribute to the antiulcer activity of the fractions.

Studies on anti-ulcer properties of Cissampelos mucronata leaf extract.

The methanolic extract of the leaves of C. mucronata was screened for anti-ulcer properties using animal models. On isolated guinea pig ileum the extract inhibited contractions evoked by acetylcholine, histamine and serotonin. The extract remarkably decreased the propulsive movement of gastrointestinal content. The extract exhibited significant anti-ulcer activity protecting rats from indomethacin, histamine and stress-induced ulcers. It inhibited the growth of both Gram-positive and Gram-negative microorganisms. The oral LD50 value of the extract in mice was estimated to be 8.5 +/- 0.35 g/kg. The results revealed that the plant C. mucronata has potential medicinal value as an anti-ulcer agent.