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Background. External infections involving the skin and wound are the most frequent complications affecting humans and animals. Medicinal plants play great roles in the treatment of skin and wound infections. This study was aimed to evaluate thein vitroantibacterial activity of crude methanolic extracts of nine medicinal plants.Methods. Agar well diffusion and broth dilution methods were used to determine the antibacterial activity of nine Ethiopian plants against four bacterial species includingStaphylococcus aureus,Pseudomonas aeruginosa,Escherichia coli, andKlebsiella pneumoniae.Results. Among the tested plants, seven (Cissus quadrangularis,Commelina benghalensis,Euphorbia heterophylla,Euphorbia prostrate,Momordica schimperiana,Trianthemaspp., andSolanum incanum) were found to exhibit considerable antibacterial activity against at least one of the test bacteria. The extracts ofC. quadrangularis,E. heterophylla, andE. prostratahad a wide spectrum of antibacterial activities against test bacterial strains while the extracts ofGrewia villosaandSchinus molledid not show any inhibitory activity. Clinical isolate and laboratory strain of S.aureusshowed the highest susceptibility to highest concentration (780 mg/mL) ofE. prostratawith a zone of inhibition of 21.0mm and 22.3mm, respectively.Conclusion. This study indicates clear evidence supporting the traditional use of seven plants in treating skin and wound infections related to bacteria.

Background. Evolution of antimalarial drug resistance makes the development of new drugs a necessity. Important source in search of such drugs is medicinal plants.Gardenia ternifoliaplant is used in Ethiopian traditional medicine for the treatment of malaria and is endowed within vitroantimalarial activity. Herein, thein vivoantimalarial activity of the plant was investigated.Methods. Acute toxicity was carried out using a standard procedure. A 4-day suppressive test was employed to evaluate the antimalarial effect of methanolic crude extract and solvent fractions of the plant. The curative and prophylactic effect of crude extract was further tested by Ranes’s test and residual infection procedure, respectively, usingPlasmodium berghei(ANKA strain) in Swiss albino mice.Results. The chemosuppressive effect exerted by the crude extract and fractions ranged between 30-59% and 14-51%, respectively. Curative and prophylactic effects of the crude extract were in the range of 36-63% and 24-37%, respectively. All dose levels of the crude extract prevented loss of weight, reduction in temperature, and anemia on early and established infection. Butanol and chloroform fractions also did reverse reduction in temperature, body weight, and packed cell volume.Conclusions. The results indicated that the plant has a promising antiplasmodial activity and it could be considered as a potential source to develop new antimalarial agents.

Background. Malaria is among the leading causes of mortality and morbidity. Moreover, the emergence of resistance to antimalarial drugs is a major problem in controlling the disease. This makes the development of novel antimalarial drugs a necessity. Medicinal plants are important sources in discovering antimalarial drugs. Schinus molle is claimed for its antimalarial effect in Ethiopian folkloric medicine and endowed with in vitro antiplasmodial activity. In the present study, the in vivo antimalarial activity of the plant was investigated. Methods. Acute toxicity was carried out using a standard procedure. To screen the in vivo antimalarial potential of the S. molle against Plasmodium berghei (ANKA), a 4-day suppressive test was employed. The extracts and fractions were given to infected mice by oral gavage at 100, 200, and 400 mg/kg/day for four consecutive days. Parameters such as parasitemia were then evaluated. Results. Any sign of toxicity was not observed in the oral acute toxicity test. The crude extracts and solvent fractions exerted a significant (p<0.05) inhibition of parasite load compared to the negative control. The highest inhibition (66.91%) was exhibited by the 400 mg/kg/day dose of 80% methanolic crude extract. Among the fractions, chloroform fraction demonstrated maximal chemosuppressive effect (55.60%). Moreover, crude extracts and solvent fractions prevented body weight loss, reduction in temperature, and anemia compared to the negative control. Except the aqueous fraction, the tested plant extracts were able to significantly prolong the survival time of infected mice. Conclusion. The findings of the present study confirmed the safety and a promising in vivo antimalarial activity of S. molle, thus supporting the traditional claim and in vitro efficacy. In-depth investigations on the plant, however, are highly recommended.

Background. The alarming spread of parasite resistance to current antimalarial agents is threatening malaria controlling efforts. This, consequently, urged the scientific community to discover novel antimalarial drugs. Successful and most potent antimalarial drugs were obtained from medicinal plants. Capsicum frutescens is claimed to possess an antiplasmodial activity in Ethiopian and Ugandan folkloric medicine. However, there is a lack of pharmacological evidence for its antiplasmodial activity. This study, hence, was aimed at evaluating the in vivo antiplasmodial activity of C. frutescens in a mouse model. Methods. The dried fruits of the plant were extracted with 80% methanol using cold maceration. A 4-day suppressive test was employed to ascertain the claimed antiplasmodial effect of the plant. Following inoculation with P. berghei, mice in treatment groups were provided with three dose levels (100, 200, and 400 mg/kg) of the extract, while 2% Tween 80 and chloroquine served as the negative and positive controls, respectively. Weight, temperature, packed cell volume, parasitemia, and survival time were then monitored. Results. The acute oral toxicity study revealed that the crude extract caused no mortality and revealed no overt sign of toxicity. In the 4-day suppressive test, all dose levels of the extract were found to exhibit a significant (p<0.05) inhibition of parasitemia compared to those of the negative control. Maximum parasite suppression (93.28%) was exerted by the highest dose (400 mg/kg/day) of extract. Also, the extract significantly (p<0.05) prolonged survival time and prevented body weight loss and reduction in temperature and anemia compared to the vehicle-treated group. Conclusion. This investigation found strong evidence that the fruit extract of C. frutescens is endowed with promising antiplasmodial activity. Hence, the plant could serve as a potential source of a newer antimalarial agent.

Background. Despite a substantial scientific progress over the past two decades, malaria continues to be a worldwide burden. Evergrowing resistance towards the currently available antimalarial drugs is a challenge to combat malaria. Medicinal plants are a promising source of new drugs to tackle this problem. Thus, the present study aimed at evaluating the antiplasmodial activity of Terminalia brownii in Plasmodium berghei infected mice. Methods. A 4-day suppressive test was employed to evaluate the antimalarial effect of 80% methanol and aqueous bark extracts of T. brownii against P. berghei in Swiss albino mice. Results. The in vivo acute toxicity test indicated that both extracts of T. brownii did not cause mortality. The 4-day early infection test revealed that the 80% methanol and aqueous extracts exhibited a significant inhibition of parasitemia p<0.001 compared to negative control. The maximum level of chemosuppression (60.2%) was exhibited at 400 mg/kg dose of 80% methanol extract. Moreover, the 80% methanol extract showed a significant p<0.001 attenuation of anemia associated with infection in a dose-dependent manner. The aqueous extract, on the other hand, exhibited a percent inhibition of 51.1% at the highest dose (400 mg/kg/day). Conclusion. The present study indicated that hydromethanolic and aqueous bark extracts of T. brownii possess a promising antimalarial activity, with higher effect exhibited by the hydromethanolic extract.

Background. Haemonchus contortus, the causative agent of Haemonchosis, is the most economically important parasite in small ruminant production. Control with chemotherapy has not been successful due to rapid emergence of drug-resistant strains. There is a continuous search for alternative leads particularly from plants. The study aimed to evaluate the anthelmintic activity of crude methanolic extracts of leaves of Schinus molle and aerial parts of Cissus quadrangularis against H. contortus. Methods. Adult motility test and egg hatching inhibition assay were employed to investigate the in vitro adulticidal and egg hatching inhibitory effects of the extracts. Results. Higher concentrations of the extracts (10 and 5 mg/ml) had a significantly superior adulticidal activity (p<0.05) compared to the negative control and lower concentration levels, which was comparable to albendazole. Similarly, the relative egg hatch inhibition efficacy of S. molle and C. quadrangularis extracts indicated a maximum of 96% and 88% egg hatch inhibition, respectively, within the 48 hrs of exposure at 1 mg/ml. Conclusion. The current study evidenced that the crude methanolic extracts of the plants have promising adulticidal and egg hatching inhibitory effects against H. contortus.