https://journal.uog.edu.et/index.php/EJNCS/issue/feed Ethiopian Journal of Natural and Computational Sciences 2024-12-24T17:12:50+00:00 Worku N. Mhiret worku.negash@uog.edu.et Open Journal Systems <p><strong>The Ethiopian Journal of Natural and Computational Sciences (<em>EJNCS</em>)</strong> is a journal that aimed publishing articles which will contribute new theoretical and practical results in all areas of Natural and Computational Sciences and related disciplines. Research papers and articles on Biological, Biotechnological, Chemical, Earth Science, mathematical, Physical, Sport, Statistical, Environmental, Agricultural, Veterinary, Technological, and Health Sciences will be covered in <em>EJNCS</em>. The frequency of its publication shall be biannual. When the demand from authors increases the publication frequency will be quarterly. Manuscript submission to the journal is through the <a href="http://journal.uog.edu.et/index.php/EJNCS">journal online submission system</a> available at the UoG website.</p> https://journal.uog.edu.et/index.php/EJNCS/article/view/970 The Association of MECA Gene Polymorphism and Drug Resistance Pattern of Methicillin-Resistant Staphylococcus Aureus Isolated from Keha and Shinta Rivers of Gondar Town, Northwest Ethiopia 2024-12-24T16:18:24+00:00 Mequanint Mulat mulatmeku35@gmail.com Tewodros Eshetie teddymulu21@gmail.com Fisseha Getachew fissehagetachew21@gmail.com Asmamaw Tesfaye asmamawtesfaye508@gmail.com Yalemwork Jenber yalem21jenber@gmail.com Belay Tilahun belayt21@gmail.com Bogale Damtew bogalebioinfo21@gmail.com Nega Berhane Berhane tsenega@yahoo.com <p style="text-align: justify;">Associated with nosocomial and community-acquired infections, <em>Staphylococcus aureus </em>is a&nbsp;potentially hazardous human bacterium that is alarmingly developing drug resistance. The&nbsp;current study's objective was to assess the association of mecA&nbsp; gene polymorphism and drug&nbsp;resistance pattern of Methicillin-resistant <em>Staphylococcus aureus </em>isolated from <em>Keha </em>and <em>Shinta&nbsp;</em>rivers of Gondar town, Northwest Ethiopia. A purposive sampling technique was used to collect&nbsp;10 water samples from&nbsp; different sites of the two rivers. Isolation of <em>S. aureus </em>was conducted&nbsp;following standard morphological and biochemical method and subjected to susceptibility testing&nbsp;to 8 antibiotics. Methicillin-resistant <em>Staphylococcus aureus </em>(MRSA) was detected by using the&nbsp;standard PCR method using specific pair of primers. The genomic DNA of the isolates was isolated using a DNA Extraction Kit (GenElutetm., USA). Amplification of mecA gene was done by PCR using a specific primer for the <em>mec</em>A gene. The PCR products were visualized using agarose gelelectrophoresis with 1.5% gel. The results indicated that four (66.7%) Methicillin-Resistant&nbsp;<em>Staphylococcus aureus </em>isolates showed to have 499 bp band size of mecA gene. <em>S. aureus&nbsp;</em>showed a wide range of resistances, with the highest levels observed for ampicillin (100%),&nbsp;penicillin, chloramphenicol, erythromycin, and tetracycline (66.7%). Instead, <em>S. aureus </em>had&nbsp;variable sensitivity to gentamycin (100%) and ciprofloxacin (100%) as well as&nbsp; vancomycin (66.7%). Four (4/6, 66.7 %) <em>S. aureus </em>isolates showed multiple antibiotic-resistant patterns&nbsp;(resistant to four or more antibiotics). The result of this finding concluded that <em>S. aureus </em>isolates&nbsp;with mecA gene developed more resistant to many antibiotics than with mecA negativeisolates. In addition, the present study confirmed that the treated wastewater mixed with the two rivers&nbsp;are potential sources of <em>S. aureus </em>and Methicillin-Resistant <em>Staphylococcus aureus infections</em>, this might be due to the poor wastewater treatment methods followed by several point sources&nbsp;in the study area. In conclusion, this study's findings suggest that the <em>Keha </em>and <em>Shinta&nbsp;</em>Rivers in Gondar Town may be potential receptacles for MRSA, which is capable of infecting&nbsp;both exposed humans and animals.</p> 2024-12-24T00:00:00+00:00 Copyright (c) 2025 Mequanint et al. https://journal.uog.edu.et/index.php/EJNCS/article/view/973 Fatty Acid Profiles of White Sesame Seeds from the Different Cultivation Areas of Ethiopia 2024-12-24T17:12:50+00:00 Bewketu Mehari Mehari bewketu.mehari@uog.edu.et Eyob Alem eyobalem816@gmail.com Tarekegn Fentie tariefen@gmail.com Worku Negash mhiret3@gmail.com Mequanint Mulat mulatmeku35@gmail.com Dereje Yenealem derenetsi@gmail.com Ayalnesh Miretie ayalnesh40@gmail.com <p style="text-align: justify;">Sesame is the second important export commodity of Ethiopia after coffee. The white&nbsp;sesame seeds (<em>Sesamum indicum </em>L.) from the main production areas of Ethiopia have not been studied comprehensibly for their chemical compositions. Hence, this study aimed to&nbsp;assess the geographical origin variations in the fatty acids composition of white sesame&nbsp;seeds. For this, fifty three white sesame seed samples from the five major producing areas (Humera, Metema, West Armachiho, Wolkayiet, Tach Armachiho) were analyzed for their&nbsp;fatty acid compositions using gas chromatography coupled with mass spectrometry (GC-MS). Nine different fatty acids were detected in all of the samples. The sesame seeds were&nbsp;rich in the essential fatty acids, linoleic acid and oleic acid, which were the most abundant&nbsp;fatty acids in the seeds with percentage compositions in the range 35.3‒48.3% and 29.8‒38.2%, respectively, across the different samples. These two fatty acids together accounted&nbsp;for 72.0‒78.8% of the total fatty acids in the samples, whereas 19.8‒22.0% was accounted&nbsp;jointly by palmitic acid and stearic acid while trace levels (all together 1.34‒2.32%) were&nbsp;palmitoleic acid, margaric acid, gadoleic acid, arachidic acid, and behenic acid. The seed oils&nbsp;showed high unsaturated-to-saturated fatty acid ratio in the range of 2.98‒3.70, which is high enough to satisfy most dietary guidelines. The oleic acid to linoleic acid ratio of the seed oils&nbsp;were in the range of 0.80–0.97, where the highest was found in seeds from Humera.&nbsp;Regarding the individual fatty acids, a significant variation (p &lt; 0.05) among production&nbsp;areas was observed only for palmitic acid and palmitoleic acid, where the highest&nbsp;concentrations were found in seeds from Humera (14.9±1.5% palmitic acid and 0.25±0.04%&nbsp;palmitoleic acid).</p> 2025-01-08T00:00:00+00:00 Copyright (c) 2025 Bewketu et al.