Anti-inflammatory activity of crude saponin extracts from five Nigerian medicinal plants

Crude saponin extracts of five medicinal plants used in the treatment of inflammatory diseases like rheumatoid arthritis, gout and haemorrhoids were screened for anti-inflammatory activity using carrageenan-induced rat paw oedema test. These plants were the whole plant of Schwenkia americana Linn (WSA), the rhizomes of Asparagus africanus Lam (RAA), the leaves of Dichrostachys cinerea Linn (LDC), the stem bark of Ficus iteophylla Miq (BFI) and the leaves of Indigofera pulchra Willd (LIP). A modify traditional method of crude saponins extraction was used to give the following percentage yields: WSA-2.74%, RAA-3.59%, LDC-1.62%, BFI-0.81% and LIP-1.57% respectively. Thin-layer chromatography was used to identify the type of saponins present in the extracts. The acute toxicity study of the crude saponin extracts in mice gave the following intraperitoneal LD50: WSA-471.2mg/kg, RAA- 1264.9mg/kg, LDC-1264.9 mg/kg, BFI-118.3mg/kg and LIP-1264.9 mg/kg respectively. The anti-inflammatory study of the extracts showed statistically significant (P<0.05) decreases in the rat paw-oedema as compared to the control. The percentage inhibitions of the extracts after four hours were as follow: WSA-61%, RAA-55%, LDC-72%, BFI-66% and LIP-40% respectively. These values were found to be comparable to that of ketoprofen-63%. The study showed that the anti-inflammatory properties attributable to these plants may be due to their saponins contents.

Evaluation of analgesic and anti-inflammatory effects of ethanol extract of Ficus iteophylla leaves in rodents

This study was undertaken to investigate the leaf part of the plant for analgesic and anti-inflammatory. The ethanol extract of Ficus iteophylla leaves (100, 200, and 400 mg kg(-1), i.p) was evaluated for analgesic and anti-inflammatory activities. The analgesic effect was studied using acetic acid-induced abdominal constriction and hot plate test in mice, while the anti-inflammatory effect was investigated using carrageenan induced paw oedema in rats. The ethanol extract at 100 mg kg(-1), 200 mg kg(-1), and 400 mg kg(-1) significantly (P< 0.05) inhibited acetic acid induced writhes by 1.50 ± 0.43, 3.0 ± 0.82 and 1.0 ± 0.82 respectively. It also exhibited significantly (P< 0.05) anti-inflammatory by 0.11 ± 0.02, 0.11 ± 0.03, 0.08 ± 0.01 respectively. The preliminary phytochemical screening of the plant extract revealed the presence of flavonoids, steroids, tannins and saponins while the effect of flavonoids, steroids and tannins on analgesic and inflammatory has been reported. The intraperitoneal median lethal dose (LD(50)) value of the extract was found to be 3807.8 mgkg(-1) body weights. The result obtained from this study shows that the extract of Ficus iteophylla contained phytochemical constituents with analgesic and anti-inflammatory activities, therefore the leaf part of the plant could be used in the management of pain and inflammatory conditions.

PRELIMINARY GASTROINTESTINAL STUDIES OF METHANOL EXTRACT OF INDIGOFERA PULCHRA WILLD IN RODENTS

In this study, the effect of the methanol extract of Indigofera pulchra Willd. (Papillionaceae) was investigated against castor oil induced diarrheoa. Its effects on perfused isolated rabbit jejunum and guinea pig ileum were also evaluated. The extract produced a dose-dependent protection against the castor oil-induced diarrheoa in mice with the highest protection (100%), obtained at 200 mgkg-1 comparable to that of loperamide (5 mgkg-1), a standard antidiarrhoeal drug. The extract (0.4 - 6.4 mgml-1) produced a concentration relaxation of the rabbit jejunum. However, no observable effect was noticed when the guinea pig ileum was treated. The extract blocked the contractile effect of acetylcholine (2 × 10-8 gml-1) and histamine (4 × 10-7 gml-1) on both rabbit jejunum and guinea pig ileum. Phytochemical screening revealed the presence of flavonoids, tannins, saponins and steroids. The intraperitoneal median lethal dose (LD50) value for the extract was found to be 2154.0 mgkg-1. The results obtained revealed that the extract possesses pharmacologically active compounds with gastrointestinal relaxant and antidiarrhoeal activities and may possibly explain the use of the plant in traditional medicine for the treatment of gastrointestinal disorder.

In vitro snake venom detoxifying action of the leaf extract of Guiera senegalensis

The extract of the leaves of Guiera senegalensis was found to detoxify (in vitro) venom from two common northern Nigerian snake species, Echis carinatus and Naja nigricollis, in separate experiments. There was a remarkable reduction in the mortality of albino mice after intra-peritoneal (i.p.) administration of reconstituted venom incubated with the extract, when compared to those challenged with the venom only. The survival of the animals exposed to the venom incubated with the different concentrations of the extract was used as the in vitro detoxification parameter.