There are frequent reports of unsafe pesticide use in many parts of Africa. Ethiopia is the second most populous nation in Africa with around 80% of the population still depending on agriculture which intensively uses pesticides. A number of studies have examined pesticide-related health and environmental risks in Ethiopia. However, most of these studies have been small in scale and it is therefore challenging to get a general overview of the extent of health risks and level of environmental contamination in the country. The aim of the present study was to synthesize and summarize contemporary knowledge on pesticide-related risks and relevant gaps in Ethiopia. An electronic database search and gathering of grey literature were done to collect information on the risks of pesticide use in Ethiopia. The electronic search was conducted using MEDLINE (via PubMed) without any publication date or language specifications. The Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) checklist was used as guide in the creation of this review. A synthesis of the reviewed studies showed evidence of health risks due to occupational pesticide exposure, surface water pollution with pesticides that could cause chronic health risks to the public, evidence of pesticide contamination of the environment (e.g., soil organisms, fish, bee colonies and wildlife) and local as well as international consumer risks due to pesticide residues in food items. In addition, there have been frequent reports of health and environmental hazards in association with cut-flower farms. There is also evidence of direct use of DDT (dichlorodiphenyltrichloroethane) on food crops and detection of DDT residues in surface water, soil and human breast milk. Those reported risks might be due to lack of knowledge among farm workers, negligence of farm owners, absence of post-registration monitoring systems and poor implementation of both national and international regulations in Ethiopia due to poor institutional capacity. The health and environmental risks of inappropriate use of pesticides requires action by all concerned bodies. Improved institutional arrangements for enforcement of regulations, awareness and further intervention studies could lessen the high risks of pesticide misuse. The authors declare no competing financial interests.

Bio-guided fractionation of seed extracts from Moringa stenopetala resulted in a myrosinase hydrolysis product, 5,5-dimethyloxazolidine-2-thione. It is formed from the glucosinolate glucoconringiin, which was identified together with O-(rhamnopyranosyloxy)benzyl glucosinolate from M. stenopetala for the first time. The glucosinolates in seeds, leaves and roots of M. stenopetala were quantified as des-sulphoglucosinolate by HPLC. The seeds without testa contained the highest concentration of glucoconringiin and of O-(rhamnopyranosyloxy)benzyl glucosinolate within the plant, 3 % and 19 % of dry mass, respectively. GLS:glucosinolate GC:glucoconringiin RB-GLS:O-(rhamnopyranosyloxy)benzyl glucosinolate

Identification of the types of strains of Mycobacterium tuberculosis (M. tuberculosis) complex causing tuberculosis (TB) could contribute to TB control program of specific geographic region as well as it could add knowledge onto the existing literature on TB worldwide. The objective of the present study was to identify the species and strains of M. tuberculosis complex causing pulmonary tuberculosis in central Ethiopia. A health institution- based cross-sectional study was conducted on 338 smear positive TB cases visiting three hospitals between October 2012 and September 2013. Morning and spot sputum samples were collected before the starting of treatment regimens. Thus, a total of 338 pooled sputum samples collected from these cases. Samples were cultured on Löwenstein Jensen media and the isolates were identified by the region of difference (RD) 9 based polymerase chain reaction (PCR) and spoligotyping. Of the total isolates 98.6% of the isolates were identified to be M. tuberculosis while the remaining 1.4% were identified as M. africanum. Further, typing of M. tuberculosis using spoligotyping lead to the identification of 90 different strains of M. tuberculosis. Of these strains, 32 were clustered consisting of more than one isolate while the remaining 58 strains were unique consisting of single isolate. Thus, 79.3% (223/281) of the isolates were found in the clustered while only 20.6% (58/281) of the strains were unique. Forty-five of the spolgotyping patterns were registeredin the SITVIT2 or SpolDB4 database in while the remaining 45 were notfound in the database and hence were orphan strains. The dominant strains were SIT53, SIT149, and SIT54, consisting of 43, 37 and 34 isolates, respectively. Classification of the spoligotype patterns using TB-insight RUN TB-Lineage showed that 86.8, 6.4, 5, 1.4% ofthe isolatesbelonged to the Euro-American lineage, East-African-Indian, Indo-oceanic and M. africanum, respectively. The identification of clustered and new strains using spolygotyping in present study does not give conclusive finding as spoligotyping has low discriminatory power. Thus, further identification of these isolates using mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VENTR) and or whole genome sequencing (WGS) recommended.

Background: Malaria remains the major health problem responsible for many mortality and morbidity in developing countries. Because of the development of resistance byPlasmodiumspecies, searching effective antimalarial agents becomes increasingly important. Pinocembrin is a flavanone previously isolated as the most active antiplasmodial compound from the leaves ofDodonaea angustifolia. For a better understanding of the antiplasmodial activity, the synthesis of pinocembrin and a great number of analogs was undertaken.Methods: Chalcones5a-rwere synthesized via Claisen-Schmidt condensation using 2,4-dibenzyloxy-6-hydroxyacetophenone and aromatic aldehydes as substrates under basic conditions. Cyclization of compounds5a-rto the corresponding dibenzylated pinocembrin analogs6a-rwas achieved using NaOAc in EtOH under reflux. Catalytic hydrogenation using 10% Pd/C as catalyst in an H-Cube Pro was used for debenzylation to deliver7a-l. The structures of the synthesized compounds were characterized using various physical and spectroscopic methods, including mp, UV, IR, NMR, MS and HRMS. The synthesized dibenzylated flavanones6a-d, 6iand7awere evaluated for their in vivo antiplasmodial activities againstPlasmodium bergheiinfected mice. Molecular docking simulation and drug likeness properties of compounds7a-lwere assessed using AutoDock Vina and SwissADME, respectively.Results: A series of chalcones5a-rhas been synthesized in yields ranging from 46 to 98%. Treatment of the chalcones5a-rwith NaOAc refluxing in EtOH afforded the dibenzylated pinocembrin analogs6a-rwith yields up to 54%. Deprotection of the dibenzylated pinocembrin analogs delivered the products7a-lin yields ranging from 78 to 94%. The dibenzylated analogs of pinocembrin displayed percent inhibition of parastaemia in the range between 17.4 and 87.2% at 30 mg/kg body weight. The parastaemia inhibition of 87.2 and 55.6% was obtained on treatment of the infected mice with pinocembrin (7a) and 4’-chloro-5,7-dibenzylpinocembrin (6e), respectively. The mean survival times of those infected mice treated with these two compounds were beyond 14 days indicating that the samples suppressedP. bergheiand reduced the overall pathogenic effect of the parasite. The molecular docking analysis of the chloro derivatives of pinocembrin revealed that compounds7a-lshow docking affinities ranging from – 8.1 to – 8.4 kcal/mol while it was -7.2 kcal/mol for chloroquine.Conclusion: Pinocembrin (7a) and 4’-chloro-5,7-dibenzyloxyflavanone (6e) displayed good antiplasmodial activity. The in silico docking simulation againstP. falciparumdihydrofolate reductase-thymidylate synthase revealed that pinocembrin (7a) and its chloro analogs7a-lshowed better binding affinity compared with chloroquine that was used as a standard drug. This is in agreement with the drug-like properties of compounds7a-lwhich fulfill Lipinski's rule of five with zero violations. Therefore, pinocembrin and its chloro analogs could serve as lead compounds for further antiplasmodial drug development.

Plant-based natural products have served as sources of remedies against pathogenic microorganisms. Although the biological activities of Viscum (Santalaceae) species are widely recognized, there is...

The aim of this study was to investigate the antiplasmodial effects of the crude aqueous, methanol and chloroform extracts of the leaves of Vernonia adoensis in Plasmodium berghei infected Swiss albino mice using Peters’ 4-day suppressive test. The number of mice used for the toxicity test was 20 (5/group) and for each extract and control groups 5 mice per group was used. The aqueous, methanol and chloroform extracts of V. adoensis leaves indicated statistically significant (P < 0.05) suppression of parasitaemia in the treated mice. The highest inhibition was that of the methanol extract treated mice (83.36%) followed by aqueous (72.26%) and chloroform (54.34%) at an oral dose of 600 mg/kg b.wt. Each extract prevented body weight loss and packed cell volume (PCV) reduction as compared to the negative control groups. The survival time of the mice treated with chloroform based on Kaplan–Meir analysis was 12.53 ± 0.37 at 600 mg/kg b.wt, while the negative control was 7.93 ± 0.37 days. The LD50 of the extracts was greater than 3000 mg/kg body weight. In conclusion, the crude leaves extract of V. adoensis have demonstrated antiplasmodial effect in vivo. P. berghei infection is suppressed in a dose-dependent manner showing relevance of the traditional use of the plant.