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Item PHYTOCHEMICAL INVESTIGATION AND ANTIBACTERIAL ACTIVITY EVALUATION OF THE ROOT EXTRACTS OF OTOSTEGIA INTEGRIFOLIA(HAWASSA UNIVERSITY, 2023-05) FELEKE TIGABIENEH MOGESMedicinal plants have been the oldest and most widely used system of medicine to treat diseases caused by different pathogens and fight infections worldwide since ancient times. Recently, including in Europe and America, there has been a growing interest in medicinal plants. Traditionally, O. integrifolia leaves have been used in Ethiopia & Eritrea as insecticides, to treat tonsillitis, uvulitis, hypertension, etc. Its roots have also been used as an anthelmintic and for the treatment of lung conditions. Thus, this study was aimed at phytochemical investigation and antibacterial activity evaluation of the root extracts of Otostegia integrifolia. The roots were collected, washed, chopped into pieces, air-dried, ground and extracted successively with CHCl3, CHCl3/CH3OH (1:1 v/v), and CH3OH to obtain 0.4, 3.77, and 1.27 % of crude extracts, respectively. The phytochemical screening test revealed the absence of alkaloids and anthraquinones and the presence of terpenoids, phenols, flavonoids, saponins, tannins, steroids, coumarins, carbohydrates, and glycosides in all extracts except phenols, which is absent in CHCl3 extracts. The CHCl3/CH3OH (1:1 v/v) extract was subjected to gradient elution of silica gel column chromatography in n-hexane/EtOAc solvent system. The elution was result in a total of 122 fractions, and fractions 48-51 (FT1) and 59-65 (FT2) had single spots on TLC. Based on the spectral data obtained from IR, 1H NMR, 13C NMR, and DEPT-135, the compounds were proposed to be hystroxene-I for FT1 and Angustanoic acid E for FT2. The extracts and isolated compounds were evaluated for their antibacterial activities against two gram positive bacterial strains (S. pyogen (ATCC19615), S. aureus (ATCC25923)) and two gram negative bacterial strains (P. aeruginosa (ATCC27853), E. coli (ATCC25922)) using ampicillin as a positive control, and all showed positive effects. Among FT1 and all the extracts FT2 exhibited the most effective antibacterial activity and the CHCl3 extract showed the least. The 400 μg/ml of isolate FT2 showed comparible effects (11.5, 12, 11, and 10.5 mm) with Ampicillin (13, 14, 12.5, and 12 mm) on S. aureus, S. pyogen, E. coli, and P. aeruginosa respectivelyItem DETERMINATION OF SELECTED ESSENTIAL AND NON- ESSENTIAL METALS IN TEFF GRAIN SAMPLES COLLECTED FROM YILMANA DENSA WOREDA, WEST GOJAM ZONE, ETHIOPIA(HAWASSA UNIVERSITY, 2024-11) ZELALEM TALACHEWTeff [Eragrostis teff (Zuccagni) Trotter] is one of the major and indigenous cereal crops in Ethiopia. Teff is a staple food in Ethiopia, consisting of two-thirds of their cereal diet and is mainly used to make human food. Although Teff is farmed for its grain, the straw is also used to build homes in both rural and urban areas, to reinforce mud or plaster, and as feed for cattl. The levels of selected essential and non-essential metals in the white, red, and mixed teff grains collected from Yilmana Densa Woreda, West Gojam Zone (Ethiopia) were determined by AAS equipped with deuterium background corrector and air-acetylene flame atomizer. After a suitable sample pretreatment, the powdered teff was wet digested with the acid mixture (8 mL HNO3:2 mL H2O2) at 180 oC for 3:00 h over wet digestion block. The accuracy of the optimized procedure was evaluated by analyzing the digest of the spiked samples with a standard solution of metals, and the percentage recoveries varied from 99 % to 113%. The mean concentrations of metals determined (mg/kg, dry weight) were in the ranges of Fe (632-761) > Mn (191-516) > Zn (87-168) > Cu (75-112) > Ni (4.15-10.81) > Co (5.36-7.15) > Cr (3.93-5.15) > Pb (1.14-2.26). A statistical analysis of variance indicated that there is significant difference between the mean concentrations of all metals (Co, Cr, Pb Ni, Fe, Mn, Cu and Zn) with (P < 0.05 at 95% confidence interval) between the different types of teff samples. . The concentrations of the metals showed that the red teff samples collected from fetlo kuskaum have higher amounts of Fe and Cu, compared to that of the white and mixed teff samples. The mixed teff samples collected from Kililt has higher amounts of Fe, Mn and Zn, compared to that of the red and white teff samples.The amount of essential metals is high in red teff samples at Fetillo Kuskuam and in mixed teff at Kililt. The presence of significant differences may be due to the presence of different geographical distribution, rainfall, soil composition, harvesting, and storing methods.Item REMOVAL OFHEAVY METALS FROM RIVER WATER USING ACTIVATED CARBON OF EUCALYPTUS GLABULUS BARK (BAHIRZAF)(HAWASSA UNIVERSITY, 2024-10) YIDAGNU FEREDEHeavy metal pollution has become one of the most serious environmental problems nowadays. The removal of heavy metals from the environment is of special concern due to their persistence. Batch experiments were conducted to test the ability of activated carbon for the removal of lead, nickel, copper and zinc from water Heavy metal pollution in the marine system has become a seriousthreattodayandofgreatenvironmentalconcernastheyarenon-biodegradableandthuspersistent. Eucalyptus glabulus bark locally named as ‘Bahirzaf’ collected aleta wendo town from area around were used for activated carbon preparation. Dumps and polluted water Activated carbon wasprepared synthesized from bio-waste materials of the plant Eucalyptus barks. This work deals with the preparation of activated carbon from Eucalyptus leave store move heavy metal ions: such as Cu(II),Pb(II),Zn (II),and Ni(II)from aqueous solution. Chemical activation of the carbon was done by H3PO4, H2SO4, KOH and Characterization includes pH. The optimum temperature used to prepare activated carbon of Eucalyptus leaves was 500 oC while the optimum pH value and contact time for activated carbon of Eucalyptus leaves was determined as6and60minrespectively.Theoptimumenvironmentsforadsorbentsdosewasdetermined0.041 g in 25 ml solution. Thermodynamic analysis asserted endothermic and spontaneous nature of the system with involvement of chemical adsorption process. Equilibrium data were represented better by the Freundlich model than the Langmuir model which describes a multilayer adsorption.Item PHYSICAL PROPERTIES AND CHEMICAL COMPOSITIONS OF PASTEURIZED COW MILK MARKETED IN ADDIS ABABA, ETHIOPIA(HAWASSA UNIVERSITY, 2024-11) WUBEDEL TEKAMilk represents an important intake in a typical diet due its high nutrient and mineral content. Consequently, milk must be of satisfactory quality in order to protect the health of the xii community. This study investigated Physical Properties and Chemical Compositions of Pasteurized Cow Milk Marketed in Addis Ababa, Ethiopian. Seven locally available pasteurized cow’s milk samples were collected and codes were given. Physical Properties and Chemical Compositions were determined following standard methods of analysis. The mean values of pH, moisture, total solids, total ash and titratable acidity were in the range of 5.81–6.42, 84.78– 91.91%, 8.09–15.16%, 0.546–0.739%, and 0.228–0.411%, respectively for the seven pasteurized milk samples. The determination of minerals in pasteurized cow’s milk samples were carried out after optimization of the digestion of milk, which were found to be (5.0 mL HNO3 (70%): 3.0 mL HClO4 (70%) volume ratio of reagents, 200 °C digestion temperature and 2:00 hours digestion time for the digestion of 5.0 mL of milk samples. The mean concentration of Ca, Mg, Cu, Mn, Ni, Co and Cr were in the range of 1041.00–1609.00 mg/L, 72.00–122.00 mg/L, 0.0351–0.0819 mg/L, 0.0511–0.1019 mg/L, 0.0601–0.0684 mg/L, 0.0518–0.0814 mg/L and 0.0531–0.0809 mg/L, respectively for the seven pasteurized cow’s milk samples. In this study, the concentration of Ni was also found to be below the detection limits for pasteurized cow’s milk samples such as AA/B1, AA/B4, and AA/B6. However, the concentration of Pb was found to be below the detection limits for all pasteurized cow’s milk samples. Results indicated that there were significant differences (P<0.05) in most of the evaluated physicochemical parameters and minerals content among the seven pasteurized milk samples. The accuracy of the method for the determination of the selected elements was evaluated through recovery experiment and it lied within the range 98.0% to 114.1%, which is in the acceptable range (80–120 %). Generally, the levels of the selected physicochemical parameters and several metals were mostly found above the safe limits adopted from international food standards like WHO/FAO.Item 1,4-BENZOQUINONE MODIFIED CARBON PASTE ELECTRODE FOR VOLTAMMETRIC INVESTIGATIONOF DOPAMINE(HAWASSA UNIVERSITY, 2025-04) KASSA BEKODopamine (DA) is one of electrochemically active molecule; electrochemical techniques currently have received great interest for their investigation due to their simplicity, cost effective, low detection limit, and fast response time. This study investigates the electrochemical oxidation of dopamine using a low-cost and sensitive voltammetric method based on a 1,4-Benzoquinone modified carbon paste electrode. Cyclic voltammetry revealed significant enhancements in the oxidative peak current for dopamine at the modified electrode compared to unmodified carbon paste electrode, indicating its electrocatalytic properties. Scan rate, pH, differential pulse amplitude, and concentration of dopamine were optimized for the investigation of dopamine. The optimized values were 100 mV/s, 7, and 240mV, respectively. The voltammogram resulted from those parameters showed that quasireversible nature of the analyte towards modified electrode with the transfer of two electrons per molecule of the analyte. The dependence of anodic peak current on the square root of scan rate with high correlation coefficients (R2 =0.99907 and scan rate (R2 =0.99103) indicated that, the diffusion control is dominant, but adsorption also plays a role. Key kinetic parameters were calculated: anodic transfer coefficient (α =0.798), diffusion coefficient (D=2.18×10−7 cm 2 /s), and heterogeneous electron transfer rate constant (Ks,h=2.26×10−4 cm/s). Anodic transfer coefficient (α =0.798) value is closer to one this suggests that anodic process is more favorable. Optimization of experimental conditions led to be a linear response for DA concentration ranging from 1.0 × 10−3 M to 3.5 × 10−3 M, with a detection limit of 1.39 × 10−4 M using cyclic voltammetry and 7.64 × 10−5 M with differential pulse voltammetry. The result suggests that 1,4-BQMCPE is a promising electrode material for the development of electrochemical sensors for DA detection.Item PHYSICOCHEMICAL CHARACTERIZATION OF THREE WHOLE GRAIN TEFF CULTIVARS GROWN IN ENOR ENER MEGER WEREDA, GURAGHE ZONE, CENTRAL ETHIOPIA REGIONAL STATE, ETHIOPIA(HAWASSA UNIVERSITY, 2024-06) FETENE BAYLIEEnor Ener Meger wereda is one of teff [Eragrostis teff (Zucc.) Trotter] growing and producing wereda’s in Guraghe zone, Central Ethiopia Regional State, Ethiopia. However, there is no information regarding the chemical composition of ‘teff’ grown in this wereda. Thus, this study was conducted to generate information on the chemical composition (proximate and mineral content) of ‘teff’ grown in Enor Ener Meger wereda and compare the result among the selected whole grain ‘teff’ samples and with the national standards for ‘teff’ flour specifications. A total of 5.0 Kg of ‘teff’ grain composite samples for each type of ‘teff’ were collected from ten farmers selected randomly from two kebeles in Enor ener meger woreda and were analysed for their physicochemical composition and mineral content. The proximate composition of whole grain ‘teff’ flours was determined using Standard methods of analysis and Flame Atomic Spectrometer was used to measure minerals content of samples. The mean ranges of values for pH, moisture, total solids, total ash, crude protein, crude fiber, crude fat, total carbohydrate, and energy were 6.36–6.77, 10.78–14.19%, 85.80–89.22%, 1.73–2.53%, 9.64–10.94%, 2.08–2.60%, 2.39–2.57%, 67.92–72.58%, and 336.56–350.36 kcal, respectively for the three whole grain ‘teff’ samples. Similarly, the mean ranges of values for calcium, magnesium, copper, and manganese were 153.29–248.54 mg/Kg, 123.93–180.20 mg/Kg, 11.66–27.20 mg/Kg, and 45.47–170.27 mg/Kg, respectively for the three whole grain ‘teff’ samples. Results indicated that there were significant differences in most of the evaluated physicochemical composition and minerals content among the three whole grains ‘teff’ samples. The results showed that key whole grain ‘teff’ samples contains relatively high amount of protein, fat and fiber than white whole grain ‘teff’ flour samples. Furthermore, minerals such as Ca, Mg, and Mn were found to be the lowest in white whole grain ‘teff’ samples. This might suggest that key whole grain ‘teff’ varieties are nutritious than the white whole grain ‘teff’ varieties. However, key whole grain ‘teff’ varieties have lower market price and social values in the community to the contraryItem A COMPARATIVE ANALYSIS OF PHYSICOCHEMICAL PARAMETERS AND MINERAL CONTENT IN COW AND CAMEL MILK FROM AGA WAYU DISTRICT, GUJI ZONE, OROMIA, ETHIOPIA(HAWASSA UNIVERSITY, 2025-06) DINAOL BAYUThis study aims to analyze and compare the physicochemical properties and mineral composition of cow’s and camel’s milk. Milk samples were collected from the Aga Wayu district in the Guji zone of the Oromia region, Ethiopia, using a proportional random sampling method. The physicochemical parameters analyzed included pH, titratable acidity, ash content, specific gravity, protein content, fat content, moisture content, total solids, and boiling point. Additionally, the concentrations of selected minerals (phosphorus, sodium, calcium, and potassium) were measured. The results showed that cow’s and camel’s milk exhibited similar physicochemical properties, with comparable pH (5.8 ± 0.5), titrateble acidity (0.20 ± 0.01), ash content (0.84 ± 0.12%), specific gravity (1.04 ± 0.11), protein content (3.32 ± 0.43%)for cow, fat content (3.6 ± 0.48%) and boiling point (92.66°C)for camel. The concentrations of sodium (3.63 ± 1.23 mg/L) and phosphorus (2.43 ± 0.39 mg/L) were also similar in both types of milk. However, cow’s milk had higher moisture content (85.13 ± 2.65%) and calcium levels (22.44 ± 2.41 mg/L) compared to camel’s milk, which had lower moisture (82.83 ± 1.22%) and calcium (17.07 ± 1.38 mg/L). Conversely, camel’s milk contained higher total solids (18.26 ± 0.50%) than cow’s milk (14.82 ± 2.11%). In conclusion, camel’s milk was found to have higher protein and lactose content than cows’s milk, while cow’s milk had a greater fat content. These findings highlight the distinct nutritional profiles of the two types of milk, which may have implications for their dietary applications.Item DETERMINATION OF SELECTED PHYSICOCHEMICAL AND MINERAL CHARACTERISTICS OF DRINKING WATER IN ANASORA DISTRICT, GUJI ZONE, OROMIA REGIONAL STATES, ETHIOPIA(HAWASSA UNIVERSITY, 2024-10) DEREJE JANBOARARSODrinking water should be free unwanted constituent, contaminant, or impurity and fulfil quality requirements (desirable and permissible limits) recommended national and international organizations. This study was done to determine the levels of selected physicochemical parameters (temperature, pH, Electrical Conductivity, Total hardness, Total Alkality, and chloride), and minerals such as (Ca, Mg ,Cr and Pb), trace elements (Cu, Mn, Ni, and Co) in drinking ground water samples sampled from selected Kebeles such as Bube Korsa, Hiyo Komele, and Irba Buliyo of Ana Sora district, Guji zone, Oromia regional state, Ethiopia. The temperature, pH, electrical conductivity, and TDS were measured using an AD8000 pH/mV/EC/TDS/Temp meter; TH, TA, and chloride were determined by titration method, while the mineral content was determined by flame atomic absorption spectrometry (FAAS). The average values of the physicochemical parameters investigated in this study were found to be in the range: temperature (20.8 – 23.1) °C, EC (3.7 – 23.7) 𝜇S/cm, TDS (8.5 – 12.8) mg/L, TH (14.7 – 42.4) mg/L, TA (23.3 – 38.3) mg/L and chloride (2.3 – 3.8) mg/L. The average concentrations of the minerals were found to be in the range of temperature: Ca (2.32 – 9.62) mg/L, Mg (11.9 –24.6) mg/L, and Cu (0.13 – 0.30) mg/L. Metals such as Mn, Ni, Co, Cr, and Pb were found to be below the detection limit of the instrument. The accuracy of the method of recovery experiment the analysis was evaluated by analyzing the digest of the spiked samples. The recoveries of the metal were in the range of 96.0to 110.0%.OneWay-ANOVA analysis showed that there were significant variations (p < 0.05) in the physicochemical parameters and metals investigated among the drinking groundwater samples. However, all the values of the physicochemical parameters investigated were found to be within the acceptable standard specified in Compulsory Ethiopian Drinking Water Specifications. Therefore, the drinking ground water supplied to the community in Ana Sora district was deemed to be safe for human consumption according to the selected parameter and, mineral set as standard.Item PHOTOCATALYTIC DEGRADATION OF CRYSTAL VIOLET UNDER SOLAR IRRADIATION USING A BIOSYNTHESIZED ZnOBASED POLYANILINE(HAWASSA UNIVERSITY, 2024-05) BELAYNESH SIRIYE TALILAA morphologically modified PANI/ZnO Nanocomposite was synthesized using leaf extract from Solanecio gigas (S. gigas) a reducing and capping agent for the photocatalytic degradation of Crystal Violet (CV) under natural sunlight irradiation. Additionally, PANI and pure ZnO NPs were synthesized via a green route, and the nanomaterials were characterized using spectroscopic techniques such as UV-Vis, FT-IR, SEM, and XRD. The blue-shift in the absorption peak of PANI/ZnO NCs suggests a change in electronic structure, potentially due to a type-II heterojunction between PANI and ZnO. FTIR analysis revealed red-shifted peaks, indicating hydrogen bonding between ZnO and PANI. Morphologically, the composite material combines the roughness of ZnO NPs with the smoothness of PANI. XRD patterns showed overlapping peaks from the composite with a crystalline size of 5.577 nm, which is smaller than the crystalline size of ZnO NPs (9.455 nm). This reduction in size is likely due to the formation of a polymer-Zn complex on the nanoparticle surface. The photocatalytic activity of the polyaniline/ZnO nanocomposite in degrading CV in aqueous solution under natural sunlight irradiation was evaluated and compared with that of ZnO nanoparticles. The effects of experimental conditions such as pH, photocatalyst dosage, and CV concentration were investigated with 91.20% and 99.06% at pH 11, 99.47% and 99.97% at 0.12 g, and 94.93% and 96.20% at 20 ppm for both ZnO NPs and PANI/ZnO NCs. The ZnO/polyaniline nanocomposite exhibited higher photocatalytic activity at 98.25% compared to ZnO nanoparticles at 92.76% under optimal conditions after 60 minutes of sunlight exposure. Kinetics studies indicated that the degradation rate fit well with the pseudo-first-order kinetics model, showing an R2 value of 0.968 for PANI/ZnO NCs. The composite demonstrated good catalytic activity with four cycles of reusability time compared to non-coated ZnO NPs. These findings highlight the potential of S. gigas plant-assisted PANI/ZnO NCs as effective and sustainable nanocatalysts with promising applications in catalytic decomposition of organic contaminants for environmental remediationItem DESIGN AND SYNTHESIS OF SOME NOVEL HYBRID MOLECULES CONTAINING INDOLE AND OXADIAZOLE RING FOR EVALUATION OF ANTIBACTERIAL AND ANTIOXIDANT ACTIVITIES(HAWASSA UNIVERSITY, 2024-05) AMANUEL ABRIHAM BUDEIndole-containing oxadiazole compounds have emerged as a versatile class of nitrogencontaining heterocyclic compounds with a wide range of biological activities. These compounds and their derivatives exhibit a diverse array of properties such as antiviral, anticancer, anti-HIV, antioxidant, antimicrobial, antidiabetic, and antimalarial activities. The aim of the study was to design and synthesize some novel hybrid molecules containing an indole and oxadiazole rings, followed by partial characterization of the synthesized compounds using UV-vis and FT-IR spectroscopic techniques, and assessment of their antibacterial and antioxidant activities. The synthetic methodology was initiated by esterification of 2-(1H-indol-3-yl) acetic acid (105aʹ) and 4-(1H-indol-3-yl) butanoic acid (105bʹ) using a catalytic amount of sulfuric acid and excess methanol. This process resulted in the formation of methyl 2-(1H-indol-3-yl)acetate (106aʹ) and methyl 4-(1H-indole-3-yl)butanoate (106bʹ) respectively. These esters were further converted to 2-(1H-indol-3-yl)acetohydrazide (107aʹ) and 4-(1H-indole-3-yl)butaneydrazide (107bʹ) respectively. Finally, the compounds (107aʹ) and (107bʹ) underwent a reaction with substituted carboxylic acids in the presence of POCl3 to produce the desired targeted compounds: 110aʹ, 111aʹ, 110bʹ, and 111bʹ. The synthesized compound yields were as follows: 110aʹ (62%), 111aʹ (55%), 110bʹ (57%), and 111bʹ (53%). The chemical structures of these synthesized compounds were partially characterized by using spectroscopic techniques like UV-Vis and FT-IR. The synthesized compounds were evaluated for their in vitro antibacterial activity test against four bacterial strains: E. coli, P. aeruginosa, S. pyogenes and S. aureus by the disk diffusion method. Among synthesized compounds, compound 111bʹ showed potent inhibitory activity against Gram-negative, E. coli with 11.57 ± 0.15 mm zone of inhibition compared to the standard drug tetracycline (13 ± 0.5 mm) at 150 mg/mL. The RSA of synthesized compounds were assessed through DPPH radical assay, revealing that compounds 111aʹ and 110aʹ demonstrated higher %RSA (91.83% and 89.9%, respectively) with IC50 values of 4.95 and 5.03, respectively, compared to the standard ascorbic acid of %RSA (87.5%) with an IC50 of 31.44 and than other synthesized compounds. Hence, the studies have indicated that all the synthesized compounds could be considered as potential candidates for further investigation in antibacterial and antioxidant research.