Antibacterial activities of selected medicinal plants in traditional treatment of human wounds in Ethiopia

Objective:To evaluate the activity of selected Ethiopian medicinal plants traditionally used for wound treatment against wound-causing bacteria.Methods:Samples of medicinal plants(Achyranthes aspera,Brucea antidysenteriea,Datura stramonium,Croton macrostachyus,Acokanthera xchimperi.,Phytolacca dodecandra,Milhttia ferruginea,and Solanum incanum)were extracted using absolute methanol and water and tested for their antimicrobial activities against clinical isolates and standard strains of wound-causing bacteria using agar well diffusion and micro titer plate methods.Results:Most of the plant extracts had antibacterial activities,among which Acokanthera schimperi and Brucea antidysenteriea inhibited growth of 100%and 35%of the test organisms,respectively.Methanolic extracts had higher activities compared with their corresponding aqueous extracts.The most susceptible organism to the extracts was Streptococcus pyogens while the most resistant were Escherichia coli and Proteus vulgaris.Conclusions:This finding justifies the use of the plants in wound healing and their potential activity against woundcausing bacteria.Their toxicity level and antimicrobial activity with different extraction solvents should further be studied to use them as sources and templates for the synthesis of drugs to control wound and other disease-causing bacteria.

Laboratory assessment of the molluscicidal and cercariacidal activities of Balanites aegyptiaca

Objective:To assess the molluscicidal and cercariacidal activities of aqueous extracts of Balanites aegyptiaca(B.aegyptiaca)against EthiopianBiomphalaria pfeifferi(B.pfeifferi),Lymnaea natalensis(L.natalensis)and Schistosoma mansoni(S.mansoni)cercariae.Methods:Extracts of seeds,endocarp,mesocarp,and fruit of B.aegyptiacawere tested for their activities against adultB.pfeifferiandL.natalensis.The cercariacidal activity of the seeds of the plant was also evaluated againstS.mansoni.Bioassays were carried out following the methods recommended by WHO.Snail mortalities were compared between each plant part and snail species,and LC50and LC90values for the plant parts tested were computed.The cercariacidal activity of the plant was assessed by exposing the mice to the cercariae pre-exposed to aqueous extract of B.aegyptiacaseeds.Results:For the molluscicidal activities of seeds,endocarp,mesocarp and whole fruit,the LC50values againstB.pfeifferiwere 56.32,77.53,65.51 and 66.63 mg/L,respectively,while the respective LC90values were 77.70,120.04,89.50 and 97.55 mg/L.Similarly,the LC50values for the seeds,endocarp,mesocarp and whole fruit againstL.natalensiswere 80.33,92.61,83.52 and 87.84mg/L,respectively,while the respective LC90values were 102.30,138.21,115.42 and 127.69 mg/L.B.pfeifferiwere found to be more susceptible toB.aegyptiacathanL.natalensis.S.mansoni cercariae exposed to 15 mg/L of extract of seeds were incapable of infecting mice.The mean egg load of tissue was reduced in mice infected with the cercariae exposed to 5 and 10 mg/L of the extract.Conclusions:The aqueous extracts of different parts ofB.aegyptiacaexhibited reasonable molluscicidal activity againstB.pfeifferiandL.natalensis,as well as cercariacidal activity againstS.mansonicercariae.However,comprehensive laboratory evaluation is recommended prior to field tests of the plant parts since their impact on other aquatic biota is not known.

Ethnobotanical survey of antimalarial plants in Awash-Fentale District of Afar Region of Ethiopia and in vivo evaluation of selected ones against Plasmodium berghei

Objective: To document plants used in traditional treatment of malaria in the Awash-Fentale District, the Afar Region of Ethiopia, and to evaluate antimalarial activity of selected ones against Plasmodium berghei in mice. Methods: Semi-structured interviews were carried out with purposively selected informants in the District to gather information on plants used in the traditional treatment of malaria. Standard procedures were used to investigate acute toxicity and a four-day suppressive effect of crude aqueous and ethanol extracts of the leaves of the two most frequently cited plants [Aloe trichosantha(A. trichosantha) and Cadaba rotundifolia(C. rotundifolia)] against Plasmodium berghei in Swiss albino mice. Results: The informants cited a total of 17 plants used in the traditional treatment of malaria in Awash-Fentale District. Plant parts were prepared as infusions or decoctions. Leaf was the most commonly cited(44%) plant part, followed by stem(22%). Shrubs were the most frequently cited(63%) medicine source followed by trees(21%). Of the 17 plants, C. rotundifolia and A. trichosantha were the most frequently mentioned plants in the district. Ethanol extracts of the leaves of C. rotundifolia and A. trichosantha suppressed P. berghei parasitaemia significantly accounting for 53.73% and 49.07%, respectively at 900 mg/kg. The plants were found to be non-toxic up to a dose of 1 500 mg/kg. Conclusions: Seventeen plant species were reported to be used for treatment of malaria in the Awash Fentale Distinct, among which A. trichosantha and C. rotundifolia were the most preferred ones. P. berghei suppressive activity of these plants may partly explain their common use in the community.