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Tetrapleura tetraptera (Schumach. And Thonn) Taub, Mimosaceae, commonly known as Aridan (fruit), A single stemmed, robust, perennial tree of about 30m.It has a grey/brown, smooth/rough bark with glabrous yound branchlets. The flower is yellow/pink and racemes white the fruit has dark brown, four winged pods 12-25 x 3.5-6.5cm.It is generally found in the lowland forest of tropical Africa. The fruit consists of a fleshy pulp with small, brownish-black seeds. The fruit possesses a fragrants, characteristically pungent aromatic odour, which is attributed to its insect repellent property. It is used as spices and aroma (exotic tropical scents) and fish poisoning. It is one of the molluscicidal medicinal plants of Nigeria, also useful in the management of convulsions, leprosy, inflammation and/or rheumatoid pains. The documented biological and-or pharmacological activities are found to be molluscicidal, cardio-vascular, neuromuscular, hypotensive, anti-convulsant, molluscicidal, trypanocidal, hirudinicidal, schistomiasis control, anti-ulcerative, ectoxicity, anti-inflammatory, hypoglycaemic, anti-microbial, emulsifying property, birth control, food value and the control of intestinal parasites. Activity-guided fractionation of the methanol extract of the fruits of T. Tetraptera led to the isolation of a saponin glycoside with an oleanolic acid aglycone, a monodesmosidic diglycoside of the rare sapogenin 27-hydroxyolean-12 (13)-en-28-oic acid; echinocystic acid-3-0-sodium sulfate from the stembark, umbelliferone and ferulic acid from the leaves and branches respectively. Also isolated from the fruits were aridanin and three of its olean-12-en-28-oic acid derivatives. All the compounds isolated either from the fruits or other parts were found to exhibit strong molluscicidal properties against the schistosomiasis-transmitting snails Biomphalaria glabrata.

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 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.

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The cardiac effects of the leaf extract and 11 isolated pure compounds have been examined on isolated, spontaneously beating, atrial muscles of the rat. Using nor-adrenaline (8 X 10(-7)M) and acetylcholine (4 X 10(-8)M) as reference drugs and normal saline (equivalent volume) as control, the crude extract of Dysoxylum lenticellare (8 X 10(-4) g/ml) induced negative chronotropic and positive inotropic responses on the isolated cardiac muscle preparations. The extract demonstrated significant (p less than 0.05-0.01) cardioactivity as attested to by its positive inotropic and/or negative chronotropic activities on the rat atrial preparations. Of the pure isolates tested, 7, 8, and 9 demonstrated significant cardiac effects. Although the precise mechanism of action of the extract or pure isolates on the atrial myocardium has not been fully determined, available experimental data suggest that the extract and pure isolates act directly on the cardiac muscle. Alkaloids 7, 8, and 9 manifest cardiac effects similar to that of the crude extract but of lesser magnitude. Some indirect effects of these isolates may, however, be associated with the manifested activities.

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