Antimicrobial activity and brine shrimp toxicity of extracts of Terminalia brownii roots and stem

BACKGROUND: Ternimalia brownii Fresen (Combretaceae) is widely used in traditional medicine to treat bacterial, fungal and viral infections. There is a need to evaluate extracts of this plant in order to provide scientific proof for it's wide application in traditional medicine system. METHODS: Extraction of stem bark, wood and whole roots of T. brownii using solvents of increasing polarity, namely, Pet ether, dichloromethane, dichloromethane: methanol (1:1), methanol and aqua, respectively, afforded dry extracts. The extracts were tested for antifungal and antibacterial activity and for brine shrimp toxicity test. RESULTS: Extracts of the stem bark, wood and whole roots of T. brownii exhibited antibacterial activity against standard strains of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella typhi, and Bacillus anthracis and the fungi, Candida albicans and Cryptococcus neoformans. Aqueous extracts exhibited the strongest activity against both bacteria and fungi. Extracts of the roots and stem bark exhibited relatively mild cytotoxic activity against brine shrimp larvae with LC(50 )values ranging from 113.75–4356.76 and 36.12–1458.81 μg/ml, respectively. The stem wood extracts exhibited the highest toxicity against the shrimps (LC(50 )values 2.58–14.88 μg/ml), while that of cyclophosphamide, a standard anticancer drug, was 16.33 (10.60–25.15) μg/ml. CONCLUSION: These test results support traditional medicinal use of, especially, aqueous extracts for the treatment of conditions such as diarrhea, and gonorrhea. The brine shrimp results depict the general trend among plants of the genus Terminalia, which are known to contain cytotoxic compounds such as hydrolysable tannins. These results warrant follow-up through bioassay-directed isolation of the active principles

Antimicrobial and brine shrimp lethality of extracts of Terminalia mollis laws

Using the disc diffusion method it was demonstrated that extracts of the leaves, stem and roots of Terminalia mollis Laws (Combretaceae) have antibacterial activity against Staphylococcus aureus (NCTC 6571), Escherichia coli (NCTC 10418), Pseudomonas aeruginosa (NCTC 10662), Klebsiella pneumoniae (NCTC 9633), Salmonella typhi (NCTC 8385), and Bacillus anthracis (NCTC 10073) and antifungal activity against Candida albicans (Strain HG 392), and local strains of Aspergillus flavus and Cryptococcus neoformans. The root extracts were the most active followed by the stem, and leaf extracts. Extracts of the three parts also exhibited cytotoxicity to brine shrimp larvae with LC50 values ranging from 26.3 to 58.1, 10.4 to 69.5, and 42.9-101.3μg/ml, for the root, stem, and leaf extracts, respectively. The results support the traditional uses of extracts of this plant for the management of bacterial and fungal infections. Keywords: Terminalia mollis, antimicrobial activity, traditional medicine African Journal of Traditional, Complementary and Alternative Medicines Vol. 3(3) 2006: 59-6

Screening of Traditionally Used Plants for In Vivo Antimalarial Activity in Mice

Aqueous ethanol (80%) extracts of six plants used traditionally for treatment of malaria, Vepris glomerata (F.Hoffm.) Engl (Rutaceae), Maranthus floribunda (Bak.) F.White (Chrysobalanaceae), Strophanthus eminii Asch. & Pax ex Pax (Apocynaceae), Cassia abbreviata Oliv. (Leguminosae) and Caesalpinia bonducella L. Fleming (Fabaceae) were screened for antimalarial activity to establish validity of their claims. The extracts exhibited antimalarial activity in the 4-day Peter's suppressive antimalarial assay in mice inoculated with red blood cells parasitized with Plasmodium berghei. The extracts gave ID50 values of 42.8, 111.0, 639.3 and 1560 mg/kg body wt for C. bonducella, C. abbreviata, T. furialis and S. eminii, respectively. The ID50 values for V. glomerata and M. floribunda were above 2400 mg/kg body wt, above which point solubility was a problem. All the tested extracts were innocuous to the mice, up to 2400 mg/kg body wt, suggesting they may be safe for short-term use

Anticonvulsant Activity of Diospyros Fischeri Root Extracts

Diospyros fischeri Gurke (Ebenaceae) is used in traditional medicine for the treatment of epilepsy. Dichloromethane, ethylacetate, and ethanol extracts of the roots, at doses between 100 and 1600 mg/kg BW, inhibited convulsions induced by the γ-aminobutyric acid type A (GABAa) receptor antagonist, pentylenetetrazole (PTZ), in a dose dependent manner. The extracts also exhibited low toxicity against brine shrimps giving LC50 values between 45.4 and 95.4 µg/ml. These results provide evidence for the potential of D. fischeri extracts to treat absence seizures, especially given their seemingly innocuous nature