Bassey S. Antia

Hypoglycemic activity of aqueous leaf extract of Persea americana Mill

Persea americana mill (lauraceae) is a tree plant also called avocado or alligator pear. It is chiefly grown in temperate regions and sparsely grown in tropical regions of the world. It is recommended for anemia, exhaustion, hypercholesterolemia, hypertension, gastritis, and gastroduodenal ulcer. The leaves have been reported as an effective antitussive, antidiabetic, and relief for arthritis pain by traditional medicine practitioners of Ibibio tribe in South Nigeria. Analgesic and antiinflammatory properties of the leaves have been reported. Although there are reports of the medicinal uses of this plant, there is no report on its antidiabetic activity. Therefore, it was thought worthwhile to evaluate its antidiabetic effects in alloxan-induced diabetic rats. In November 2004, the fresh leaves of Persea americana were collected from the farm of the Faculty of Agriculture, University of Uyo, Uyo, Nigeria. The plant was identified and authenticated by Dr. (Mrs) Margaret Bassey, a taxonomist in the Department of Botany, University of Uyo, Uyo, Nigeria. The leaves were shade dried for a period of 10 days. It was pulverized in wooden mortar and 100 g of the powder was macerated in 300 mL of water in a conical flask for 72 h. The liquid filtrate was concentrated in vacuo at 40 C. The yield was 2.67%. The dried extract was formulated as suspension in distilled water using Tween 80 as suspending agent. The extract was chemically tested for the presence of different chemical constituents using standard methods. Adult albino Wistar rats (150-180 g) of either sex obtained from University of Uyo, animal house, Uyo, Nigeria were used for the study. The animals were acclimatized for a period of 10 days to room temperature (28 ± 5 C) with a relative humidity of 50%. They were housed in standard cages and maintained on standard pellets and water ad libitum. Approval for animal studies were obtained from the College of Health Sciences Animal Ethics Committee, University of Uyo. Hypoglycemic activity of aqueous leaf extract of Persea americana Mill

In vivo antimalarial activity of ethanolic leaf extract of Stachytarpheta cayennensis.

OBJECTIVE To evaluate the in vivo antiplasmodial activity of the ethanol leaf extract of Stachytarpheta cayennensis in the treatment of various ailment in Niger Delta region of Nigeria, in Plasmodium berghei infected mice. MATERIALS AND METHODS The ethanolic leaf extract of Stachytarpheta cayennensis (90-270 mg/kg/day) was screened for blood schizonticidal activity against chloroquine sensitive Plasmodium berghei berghei in mice. The schizonticidal effect during early and established infections was investigated. RESULT Stachytarpheta cayennensis (90-270 mg/kg/day) exhibited significant (P< 0.05) blood schizonticidal activity both in 4-day early infection test and in established infection with a considerable mean survival time comparable to that of the standard drug, chloroquine, 5 mg/kg/day. CONCLUSION The leaf extract possesses significant (P< 0.05) antiplasmodial activity which confirms its use in folkloric medicine in the treatment of malaria.

Antidiabetic activities of ethanolic extract and fraction of Anthocleista djalonensis

OBJECTIVE To evaluate the antidiabetic activities of ethanolic root extract/fraction of Anthocleista djalonensis (A. djalonensis) in alloxan-induced diabetic rats. METHODS A. djalonensis root extract/fractions (37-111 mg/kg) were administered to alloxan-induced diabetic rats for 14 days and blood glucose levels (BGLs) of the diabetic rats were monitored at intervals of hours and days throughout the duration of the treatment. RESULTS Treatment of alloxan-induced diabetic rats with the extract/fractions caused a significant (P<0.001) reduction in fasting BGLs of the diabetic rats both in acute study and prolonged treatment (2 weeks). The activities of the extract and fractions were more than that of the reference drug, glibenclamide. CONCLUSIONS These results suggest that the root extract/fractions of A. djalonensis possess antidiabetic effect on alloxan-induced diabetic rats and this justifies its use in ethnomedicine and can be exploited in the management of diabetes.

Antimalarial and antiplasmodial activity of husk extract and fractions of Zea mays

Abstract Context: Zea mays L. (Poacae) husk decoctions are traditionally used in the treatment of malaria by various tribes in Nigeria. Objective: To assess the antimalarial and antiplasmodial potentials of the husk extract and fractions on malaria parasites using in vivo and in vitro models. Materials and methods: The ethanol husk extract and fractions (187–748 mg/kg, p.o.) of Zea mays were investigated for antimalarial activity against Plasmodium berghei using rodent (mice) malaria models and in vitro activity against chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of Plasmodium falciparum using the SRBR green assay method. Median lethal dose and cytotoxic activities against HeLa and HEKS cells were also carried out. The GCMS analysis of the most active fraction was carried out. Results: The husk extract (187–748 mg/kg, p.o.) with LD50 of 1874.83 mg/kg was found to exert significant (p < 0.05–0.001) antimalarial activity against P. berghei infection in suppressive, prophylactive and curative tests. The crude extract and fractions also exerted prominent activity against both chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of P. falciparum with the ethyl acetate fraction exerting the highest activity with IC50 values of 9.31 ± 0.46 μg/mL (Pf 3D7) and 3.69 ± 0.66 μg/mL (Pf INDO). The crude extract and fractions were not cytotoxic to the two cell lines tested with IC50 values of >100 μg/mL against both HeLa and HEKS cell lines. Discussion and conclusion: These results suggest that the husk extract/fractions of Zea mays possesses antimalarial and antiplasmodial activities and these justify its use in ethnomedicine to treat malaria infections.