Evaluation of antitrypanosomal and anti inflammatory activities of selected Nigerian medicinal plants in mice.

The extracts of nine selected Nigerian medicinal plants were investigated on Trypanosoma brucei brucei infected mice. The anti-inflammatory properties of hexane fraction of the most promising U. chamae extract was assessed by acute oedema of the mice paw model while the modulatory effect of the extract on Delayed-Type Hypersensitivity (DTH) response on in vivo leucocytes mobilization was evaluated. 'Dose-probing acute toxicity tests' established an oral and intraperitoneal LD50 for T. ivorensis stem bark as >1600 < 5000 mg/kg and 100 mg/kg respectively, while the oral LD50 of Uvaria. chamae was >5000 mg/kg. Extracts of Khaya senegalensis, Harungana madagascariensis, Terminalia ivorensis, Curcuma longa, Ocimum gratissimum and Alcornea cordifolia showed weak anti-trypanosomal effect and did not exhibit significant clearance in parasitemia at the test dose administered compared with the positive control (Diminal®). However, the leaf extract of U. chamae and its hexane fraction demonstrated a significant response (P < 0.01). The fraction at 1000 mg/kg inhibited oedema by 107%. Uvaria. chamae demonstrated both antitrypanosomal and anti-inflammatory properties by increasing the survival time of infected mice due to reduction in parasitemia caused by T. brucei brucei.

Antimicrobial and Antioxidant Activities of Some Nigerian Medicinal Plants

Ten Nigerian plants suggested from their ethnomedical uses to possess antimicrobial and antioxidant activities were studied for their anti-microbial and anti-oxidant properties. Antimicrobial activity was tested against Escherichia coli NCTC 10418, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Candida albicans, Candida pseudotropicalis and Trichophyton rubrum (clinical isolate). Trichilia heudelotti leaf extract showed both antibacterial and antifungal activities and was the most active against all the strains of bacteria tested. Boerhavia diffusa, Markhamia tomentosa and T. heudelotti leaf extracts inhibited the gram negative bacteria E.coli and P. aeruginosa strains whereas those of M. tomentosa, T. heudelotti and Sphenoceutrum jollyamum root inhibited at least one of the fungi tested. At a concentration of 312 µg/ml, hexane and chloroform fractions of T. heudelotti extract inhibited 6 and 14% of the fifty mult-idrug resistant bacteria isolates from clinical infectins, respectively. At ≤ 5mg/ml, the CHCl3 (64%) and aqueous (22%) fractions of T. heudelotti and those of CHCl3 (34%) and EtOAC (48%) of M. tomentosa gave the highest inhibition that was stronger than their corresponding methanol extracts. The corresponding EC50 of the extracts on M. acuminata, T. heudelotti, E. senegalensis and M. tomentosa were 4.00, 6.50, 13.33, and 16.50 ig/ml using the TLC staining and 1,1-dipheyl-2-picry-hydrazyl (DPPH) free radical scavenging assay. Therefore, leaf extracts of M. tomentosa and T. heudelotti, especially the latter, possess strong antimicrobial and antioxidant activities and should be further investigated. These activities justified the ethnomedical uses of these plants

Antimicrobial and antioxidant activities of some Nigerian medicinal plants.

Ten Nigerian plants suggested from their ethnomedical uses to possess antimicrobial and antioxidant activities were studied for their anti-microbial and anti-oxidant properties. Antimicrobial activity was tested against Escherichia coli NCTC 10418, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Candida albicans, Candida pseudotropicalis and Trichophyton rubrum (clinical isolate). Trichilia heudelotti leaf extract showed both antibacterial and antifungal activities and was the most active against all the strains of bacteria tested. Boerhavia diffusa, Markhamia tomentosa and T. heudelotti leaf extracts inhibited the gram negative bacteria E. coli and P. aeruginosa strains whereas those of M. tomentosa, T. heudelotti and Sphenoceutrum jollyamum root inhibited at least one of the fungi tested. At a concentration of 312 microg/ml, hexane and chloroform fractions of T. heudelotti extract inhibited 6 and 14% of the fifty multi-drug resistant bacteria isolates from clinical infections, respectively. At < or = 5 mg/ml, the CHCl(3) (64%) and aqueous (22%) fractions of T. heudelotti and those of CHCl(3) (34%) and EtOAC (48%) of M. tomentosa gave the highest inhibition that was stronger than their corresponding methanol extracts. The corresponding EC(50) of the extracts on M. acuminata, T. heudelotti, E. senegalensis and M. tomentosa were 4.00, 6.50, 13.33, and 16.50 ig/ml using the TLC staining and 1,1-dipheyl-2-picry-hydrazyl (DPPH) free radical scavenging assay. Therefore, leaf extracts of M. tomentosa and T. heudelotti, especially the latter, possess strong antimicrobial and antioxidant activities and should be further investigated. These activities justified the ethnomedical uses of these plants.

Antimicrobial activity of Bridelia ferruginea fruit.

Bridelia ferruginea fruit 60% methanolic extract exhibited antimicrobial activity against seven out of eight bacterial isolates at a concentration of 20 mg/ml.