Ariaya Hymete - Academia.edu (original) (raw)

Papers by Ariaya Hymete

BMC Chemistry

Quinazolinones are a diverse group of nitrogen-containing heterocyclic compounds with promising a... more Quinazolinones are a diverse group of nitrogen-containing heterocyclic compounds with promising antimalarial and antileishmanial activities. Herein, some 3-aryl-2-styryl substituted-4(3H)-quinazolinones were synthesized via cyclization, condensation, and hydrolysis reactions. 1H NMR, FTIR and elemental microanalysis was used to verify the structures of the synthesized compounds. The in vivo antimalarial and in vitro antileishmanial activities of the target compounds were investigated using mice infected with Plasmodium berghi ANKA and Leishmania donovani strain, respectively. Among the test compounds, 8 and 10 showed better antimalarial activities with percent suppression of 70.01 and 74.18, respectively. In addition, (E)-2-(4-nitrostyryl)-3-phenylquinazolin-4(3H)-one (6) showed promising antileishmanial activity (IC50 = 0.0212 µg/mL). It is two and 150 times more active than the standard drugs amphotericin B deoxycholate (IC50 = 0.0460 µg/mL) and miltefosine (IC 50 = 3.1911 µg/mL),...

Environmental Monitoring and Assessment

Acta Chromatographica

The original article has been corrected. Unfortunately, the first author's given name was publish... more The original article has been corrected. Unfortunately, the first author's given name was published with a spelling mistake (Almas), whereas the correct spelling of the name is Almaz.

The binary mixture of ampicillin sodium and sulbactam sodium is officially analyzed by HPLC but c... more The binary mixture of ampicillin sodium and sulbactam sodium is officially analyzed by HPLC but can not be simultaneously determined by the normal spectrophotometric techniques since their absorption spectra have a strong degree of overlapping. The current study developed chemometrics-assisted techniques for the simultaneous determination of the two drugs without performing any chemical separation process. Derivative spectrophotometry, derivative ratio spectrophotometry, classical least square (CLS) technique and principal component regression (PCR) technique were tried for the same purpose. Derivative spectrophotometric technique was not successful as the overlapping absorption spectra of the two drugs could not be resolved from each other using this technique. Derivative ratio technique showed a better result as it separated the two drugs to a better extent. The CLS and PCR methods were found to be capable of separating and hence determining the two drugs simultaneously. The recov...

Journal of Bioanalysis & Biomedicine, 2015

The concentration of some heavy metals was determined in barley locally grown for brewing and its... more The concentration of some heavy metals was determined in barley locally grown for brewing and its malt in Ethiopia. The samples were digested in nitric acid and hydrogen peroxide, and analysed by atomic absorption spectrometry equipped with deuterium arc background corrector. The concentrations of Cd, Cu, Mn, Pb and Zn in barley, and the levels of Cu, Mn and Zn in malt were above the maximum permissible limits in cereal grains set by Food and Agriculture Organization/World Health Organization except Cd in barley grains from West Arsi Zone. Even though Cd and Pb were found in barley grains, they were below the limits of detection in malt. The result of the survey confirmed that the Cd and Pb content in locally malted barley do not pose a risk to consumers' health though the bio-important metals could do. However, the levels of heavy metals in locally grown barley and its malt need to be regularly monitored.

A simple, accurate and precise HPTLC-densitometry method for the simultaneous determination of ab... more A simple, accurate and precise HPTLC-densitometry method for the simultaneous determination of abacavir, lamivudine and zidovudine in pharmaceutical tablet has been developed. Separation of tablet components was performed on aluminum backed HPTLC plates (silica gel 60 F 254 20×20 cm with 0.2 mm thickness, Camag, Muttenz, Switzerland) using methanol : chloroform : acetonitrile (4 : 8 : 3 v/v). Good sensitivity for all analytes was observed with UV detection at 275 nm. The method was validated for linearity, accuracy, precision, specificity and robustness. The method allowed quantitation over the 200-1450 ng/band range for the three components. Both linear and second order polynomial relationships were studied. Second order polynomial fit was found to be more suitable and its residuals plot showed a much better fitting than that of linear model, indicating good correlation and determinations (r = 0.99995, 0.9998 and 0.9998 and r 2 = 0.9999, 0.9997 and 0.9996 for 3-TC, ABC and AZT, respectively). The method has an accuracy of 99.35, 99.19 and 99.13 % for 3-TC, ABC and AZT respectively. The method is robust and has the potential to determine these drug substances simultaneously from the dosage forms.

Medicinal Plants - International Journal of Phytomedicines and Related Industries, 2011

The antibacterial activity of volatile fractions from Artemesia abyssinthium, Croton macrostachyu... more The antibacterial activity of volatile fractions from Artemesia abyssinthium, Croton macrostachyus, Echinops kebericho and Satureja punctata has been tested against selected Gram-positive and Gram-negative bacterial strains. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of five essential oils were investigated for their antibacterial activities against four gram-positive (Staphylococcus aureus (ATCC 25923), Streptococcus pyogenes, Listeria monocytogenes and Bacillus cereus) and seven gram-negative (Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Salmonella paratyphi, Shigella dysenteriae, Citrobacter sp., Klebsiella pneumonia and Proteus mirabilis) bacterial species. All the essential oils were active against all tested bacterial species. L. monocytogenes, B. cereus, and S. aureus were the three most sensitive bacteria with a mean concentration of 0.14, 0.8 and 0.62µg/ml, respectively. Almost all the essential oils have shown least activities against L. monocytogenes. In contrast, antibacterial activities were highest against S. paratyphi, P. mirabilis and E. coli with a mean concentration of 20.8, 18.8 and 15.7µl/ml, respectively. P. aeruginosa was found to be the most sensitive bacteria to all essential oils showing MIC of 0.1 to 1.6 with overall mean values of 0.62µl/ml while K. pneumonia ranked next with MIC mean values of 1.36µl/ml. The mean MIC values of the essential oils against B. cereus were significantly higher than the control (P= 0.013) whereas the essential oils against L. monocytogenes and S. aureus had comparable antibacterial activity with the control drug (P>0.05). The mean of MIC values were significantly higher against Gram-positive than Gram-negative bacteria (P<0.001).

Natural Product Research, 2005

The hexane fraction from the roots of Echinops ellenbeckii O. Hoffm. from Ethiopia yielded seven ... more The hexane fraction from the roots of Echinops ellenbeckii O. Hoffm. from Ethiopia yielded seven acetylenic thiophenes of which five compounds (1, 3, 4, 6, 7) are reported for the first time in this species: the monothiophenes 5-(penta-1,3-diynyl)-2-(but-3-en-1-ynyl)-thiophene (1), 5-(penta-1,3-diynyl)-2-(4-acetoxy-but-1-ynyl)-thiophene (2), 5-(penta-1,3-diynyl)-2-(3-hydroxy-4-acetoxy-but-1-ynyl)-thiophene (3), 5-(penta-1,3-diynyl)-2-(3,4-diacetoxy-but-1-ynyl)-thiophene (4), 5-(penta-1,3-diynyl)-2-(3-chloro-4-acetoxy-but-1-ynyl)-thiophene (5), 5-(penta-1,3-diynyl)-2-(3,4-epoxy-but-1-ynyl)-thiophene (6) and the dithiophene 5-[(5-acetoxymethyl-2-thienyl)-2-(but-3-en-1-ynyl)]-thiophene (7). Additionally, four fatty acids (C14, C15, C16 and C18), seven fatty acid esters and three long-chain hydrocarbons could be identified. All the structures were elucidated on the basis of spectral data by GC-MS, HRMS and the NMR techniques.

Mini-Reviews in Medicinal Chemistry, 2010

Flavour and Fragrance Journal, 2006

ABSTRACT Essential oil (EO) from the seeds and husks of Aframomum corrorima (Braun) P.C.M. Jansen... more ABSTRACT Essential oil (EO) from the seeds and husks of Aframomum corrorima (Braun) P.C.M. Jansen were analyzed by gas chromatography (GC/FID and GC/MS), and fifty-five compounds were identified. The main constituents found in the seed EO were the monoterpenes 1,8-cineole (44.3 %) and sabinene (17.3 %), whereas sesquiterpenic structures (2 %) such as (E)-nerolidol (17.2 %), beta-caryophyllene (9.7 %) and caryophyllene oxide (6.9 %) were dominating in husk EO.

Chemistry & Biodiversity, 2010

Essential oils of Artemisia abyssinica and Satureja punctata ssp. punctata from Ethiopia were ana... more Essential oils of Artemisia abyssinica and Satureja punctata ssp. punctata from Ethiopia were analyzed by GC and GC/MS, and screened for leishmanicidal activity against promastigote and axenic amastigotes of Leishmania donovani and L. aethiopica, including toxicity studies on human monocytic leukemia cells (THP-1) and erythrocytes in vitro. GC/MS of A. abyssinica oil revealed 67 compounds (99.94%) with the major constituents yomogi alcohol (38.47%), artemisyl acetate (24.88%), and artemisia alcohol (6.70%), and oxygenated monoterpenes (84.00%) as the dominant group. The oil of S. punctata contained 67 compounds (99.49%) with the main constituents geranial (27.62%), neral (21.72%), a-bisabolol (13.62%), and (E)-nerolidol (4.82%), of which oxygenated mono-and sesquiterpenes (58.39 and 26.91%, resp.) showed highest abundance. Both oils showed effect on promastigotes (MIC 76.5 to 312.5 nl/ml) and amastigotes (EC 50 4.06 to 131.00 nl/ml) of L. donovani and L. aethiopica, and varying toxicities on THP-1 cells (CC 50 0.013 to 350 nl/ml with selectivity index between 0.001 and 28) and erythrocytes (with LC 50 0.35 to 1.52 ml/ml). S. punctata oil exerted highest activity against both Leishmania sp. and toxicity. The revealed antileishmanial activities support further isolation and investigation of oil constituents for in vitro/in vivo evaluation.

Bulletin of Environmental Contamination and Toxicology, 2011

The present study investigated the presence and level of pesticide residues in wheat and khat sam... more The present study investigated the presence and level of pesticide residues in wheat and khat samples collected from various localities of Ethiopia. The khat samples from Galemso and Aseno had p,p'-DDT concentrations ranged from 141.2 to 973.0 lg/Kg and 194.3-999.0 lg/Kg, respectively. Diazinon was detected in all the khat samples from BadaBuna (173.9-686.9 lg/Kg) but not in any of the samples from Galemso and Aseno. Diazinon was detected in all the wheat samples obtained from both Arsi and Bale (125.8 and 125.6 lg/Kg, respectively) and aldrin levels in these samples were below the quantification limit. Khat may be a contributing factor in the pathological diseases found among khat users. Keywords Pesticides Á Wheat Á Khat Á Ethiopia The use of pesticides is considered to be indispensable practice for the production of adequate food supply for the increasing world population and for the control of insectborne diseases (Rissato et al. 2007). Thus contamination of the environment with pesticides and the pesticides entry into the food chain is unavoidable especially in developing countries. Organochlorines that enter the food chain bioaccumulate due to their lipophilicity and remain in ecosystems for a long period of time (Dehn et al. 2005). Monitoring studies from Asia revealed widespread contamination of foodstuff and animal feed with pesticide residues (Seok et al. 2008). Agricultural intensification, including increased use of pesticides, is considered a viable option in Ethiopia to overcome the problems of increasing population, shrinking arable land and food insecurity. Government extension services promote the use of pesticides to improve the productivity of smallholder agriculture and alleviate food insecurity (Environment and Social Assessment International 2006). Inventories carried out in Ethiopia showed the presence of over 400 stores with 1,500 tones of obsolete pesticides and 1,000 tonnes of contaminated equipment. Poor storage conditions (e.g. leaking drums, burst open sacks) and stock managements lent to a great risk of contamination and posed a great threat to human health and the environment. This led to the situation where Ethiopia was considered to be one of the worst contaminated countries in Africa (Environment and Social Assessment International 2006). Despite the ban of DDT in the 1970 s and the commitment of the international community to eliminate the use of 12 persistent organic pollutants, including DDT, which was demonstrated by the signage of over 90 countries on the ''Stockholm Convention on Persistent Organic Pollutants'' in 2001, the use of DDT still continuing in

Pharmacognosy Journal, 2010

PLOS ONE

Background Iodine is one of the crucial micronutrients needed by the human body, and is vitally i... more Background Iodine is one of the crucial micronutrients needed by the human body, and is vitally important during pregnancy. This study aimed to determine the relationship between the iodine status of pregnant women and their knowledge, and practices regarding iodized salt. All participants were enrolled in the Butajira nutrition, mental health and pregnancy (BUNMAP) cohort, Butajira, Ethiopia in February-May, 2019. Methods In this cross-sectional study, 152 pregnant women without hypertension or known thyroid disease before or during pregnancy were randomly selected from the BUNMAP mother to child cohort (n = 832). Spot urine samples were collected to estimate the level of urinary iodine concentration (UIC). Salt samples were also collected from their homes. The Sandall-Kolthoff (S-K) method was used to measure the level of iodine in the urine samples, and iodometric titration was used to measure the level of iodine in the salt. Data was entered and cleaned using Epi-info version 3....

Journal of Enzyme Inhibition and Medicinal Chemistry

International Journal for Parasitology: Drugs and Drug Resistance, 2022

Lobelia giberroa Hemsl. is an endogenous Ethiopian medicinal plant with a long history of use in ... more Lobelia giberroa Hemsl. is an endogenous Ethiopian medicinal plant with a long history of use in the treatment of malaria, bacterial and fungal diseases, and cancer. Here, we present the in vivo bioassay-guided fractionation of the 80% methanol extract of L. giberroa roots, which led to the isolation of lobetyolin. L. giberroa roots were extracted with 80% methanol, and the dried 80% methanol extract was fractionated with hexane, ethyl acetate, methanol, and water. Acute oral toxicity study was conducted according to the Organisation for Economic Co-operation and Development Guideline 425 by using female Swiss albino mice. Antimalarial activity was assessed in Plasmodium berghei-infected Swiss albino mice. Through in vivo bioassay-guided fractionation processes lobetyolin, a C14-polyacetylene glucoside, was isolated from the methanol fraction by silica gel column chromatography as the main active ingredient from the plant. The chemical structure of lobetyolin was elucidated by interpretation of spectroscopic data (1HNMR, 13CNMR, IR. MS) including two dimensional NMR. The plant extract was considered safe for administration up to 2000 mg/kg. In the four-day suppressive test, the 80% methanol extract (400 mg/kg), methanol fraction (400 mg/kg), and lobetyolin (100 mg/kg) exhibited antimalarial activity, with chemosuppression values of 73.05, 64.37, and 68.21%, respectively. Compared to the negative control, which had a mean survival time of 7 days, the lobetyolin (100 mg/kg) and methanol fraction (400 mg/kg) treated groups had mean survival times of 18 and 19 days, respectively. The current study supports the traditional use of the plant for the treatment of malaria. The structural differences between lobetyolin and existing antimalarials, as well as its previously unknown antimalarial activity, make it of interest as an early lead compound for further chemical optimization.

In this study, an attempt was made to assess the physicochemical equivalence of four brands of Er... more In this study, an attempt was made to assess the physicochemical equivalence of four brands of Erythromycin stearate tablets marketed in Addis Ababa. Identity, weight uniformity, disintegration, dissolution and assay for the content of active ingredients were evaluated using the methods described in the British Pharmacopoeia 2007. All the samples passed the identity, disintegration, and dissolution tests but Erythromycin stearate (Produced in Sudan by General Medicines Company) failed to release 80 % of the drug content within 45 minutes. It also failed to fulfill the tolerance limits for assay stipulated in the pharmacopoeia. This product therefore does not comply with the BP 2007 dissolution and Assay tolerance limits. This work revealed that the four products included in the study complied with the physicochemical quality parameters except Erythromycin stearate which failed to meet the pharmacopoeial specification for dissolution test and assay.

The reaction of anthranilic acid with acetic anhydride produced acetanthranil. Further reacting t... more The reaction of anthranilic acid with acetic anhydride produced acetanthranil. Further reacting the product with aromatic amines and aromatic aldehydes respectively produces a series of 2, 3-disubstituted4(3H)-quinazolinone derivative. Compounds IVa-f were synthesized to investigate their anti-malarial activities. The in vivo anti-malarial activity of these compounds was tested on P.berghei infected mice at two doses (48.46 mol/kg/day and 96.92 mol/kg/day). Most active compounds IVa (64.02%), IVc (77.25%) and IVe (73.54%) showed a dose dependent increase in antimalarial activities. Invivo acute toxicity studies of these compounds IVa-f indicates all to be non-toxic and well tolerated by the experimental animals up to 300 mg/ kg administered orally and 140mg/ kg administered parenterally. Therefore, test compounds IVa-f would represent a successful lead compound for the development of new class for anti-malarial agents.

World Academy of Science, Engineering and Technology, International Journal of Pharmacological and Pharmaceutical Sciences, 2017