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Chemical properties of any lignocellulose species are one of the major properties that used to select the material for any purpose either chemical or biological. Since bamboo is one of the woody grass species used for various applications worldwide; therefore knowing the chemical composition plays greater a role. Based on the above assumption, this research was conducted to study the major chemical composition of Yushania alpina (K. Schum.) W.C.Lin (1974) (Highland Bamboo) grown around Enjibara in Ethiopia. In the work, Yushania alpina (Highland Bamboo) sample was harvested, dried, milled using a Wiley Mill, sieved and all chemical composition were determined based on the National Renewable Energy Laboratory (ASTM) approaches, except that the Kurschner-Hoffer method (1931) was applied for cellulose determination. Based on the study, the chemical composition characterization shows that Yushania alpina has 46.76% cellulose content, 25.27% lignin content, 12.18% hemicellulose, 3.77% ash, 12.23% hot-water extractive and 3.93% ethanol-toluene extractives. [ABSTRACT FROM AUTHOR]

The concentrations of major (Na, K, Ca) and trace (Fe, Co, Cu, Mn, Zn, Ni, Cr, Cd and Pb) metals were determined in Ethiopian red pepper samples collected from Alaba, Mareko and Addis Ababa open market (Merkato) using flame atomic absorption spectrometry after wet digestion. The metal concentrations in the samples were found to be K 2378-2486, Ca 161- 222, Na 75.0-93.0, Fe 99.5-157, Cr 27.5-78.6, Zn 20.8-58.4, Mn 9.72-18.9, Ni 2.71-6.68, Cu 2.12-3.71, Co 1.02-2.24 and Cd 0.18-0.23 in μg g-1, respectively. Pb was not detected in any of the pepper samples. The levels of metals K, Na and Ca in the red pepper samples from Alaba were found to be higher than those from Mareko and Addis Ababa open market. The levels of Co, Cu, Ni, Zn and Cd were found to be higher in samples from Mareko than in samples from Alaba and Addis Ababa open market pepper. The levels of Cr and Mn were higher in Addis Ababa open market pepper. The concentrations of metals in Ethiopian pepper are comparable to values reported in literature from different parts of the world. The trace metals levels in all the three samples were found to be lower than the World Health Organization (WHO) allowed limit. However, levels of Cd and Cr were above the WHO limit. The concentrations of metals in Ethiopian red pepper are comparable to values reported in the other spices in the literature. Furthermore, to correlate metal concentrations among each other metal levels in the red pepper using Pearson's correlation coefficient (r) was determined and except for few metals, most relationships showed either strong positive or negative linear relationships. From this relationship it can be understood that the presence of one metal in the plant influence the presence of the other. [ABSTRACT FROM AUTHOR]

Indigenous fermented beverages are very popular traditional drinks in Ethiopia. Among these, korefe, tej and tella are very common in northern part of Ethiopia. However, there is no any report on the total polyphenol, flavonoid, tannin and antioxidant activity of these beverages. The purposes of this study were to determine total phenolic, flavonoids, tannins, and their antioxidant activity and to compare these parameters of selected Ethiopian traditional alcoholic beverages (korefe, tej and tella) from different origins of Ethiopia within the same sample type and between different sample types. For these purposes, methanolic extracts (70%) were prepared for semi-solid samples. Total phenolic content was determined by Folin-Ciocalteu's method, total flavonoids content was determined by aluminium chloride (AlCl3) method, total tannin content was determined by indirect method precipitating protein with gelatin, while 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity method was used to determine the total antioxidant activity. The total phenolic content obtained as gallic acid equivalent, GAE mg L-1 was: korefe (285-326), tej (369-390) and tella (435-459); the total flavonoids content obtained as catechin equivalent, CE mg L-1 was: korefe (190-199), tej (183-190) and tella (211-216); the total tannin content obtained as tannic acid equivalent, TAE mg L-1 was: korefe (19.9-25.9), tej (17.9-19.4) and tella (28.8-30.8) and the total antioxidant activity obtained as ascorbic acid equivalent, AAE mgL-1 was: korefe (479-498), tej (465-479) and tella (541-561). Statistically at 95% confidence level one way ANOVA displayed that the levels of total polyphenol, flavonoid, tannin and antioxidant activity were significantly different between korefe, tej and tella. For all the determined parameters, tella exhibited a highest value. Pearson correlation showed there were positive correlations between phenolic, flavonoids and tannin with antioxidant activity assayed (r = 0.969, r = 0.931 and r = 0.944, respectively). [ABSTRACT FROM AUTHOR]

This study reports the levels of metals in commercially available imported and Ethiopian rice. The levels of thirteen metals (Ca, Mg, K, Na, Fe, Mn, Zn, Cu, Co, Ni, Cr, Cd and Pb) were determined in six varieties of raw rice collected from Addis Ababa supermarkets, Fogera town and Amahara Regional Agricultural Research Institute and in one selected cooked rice by flame atomic absorption spectrometry (FAAS) after digesting the powdered rice samples with HNO3, HClO4 and H2O2 mixture. The validation of optimized digestion procedure was evaluated using spiking method and an acceptable percentage recovery was obtained. The levels of metals found in the imported and Ethiopian rice, respectively, were in the ranges (mg/kg): Ca 75.8- 630, 205-427; Mg 90.6-150, 99.5-2250; K 1680-2150, 1100-3020; Na 70.6-78.6, 26.7-80.9; Fe 48.9-117, 41.3-113; Mn 4.1-15.5, 3.7-16.6; Zn 16.4-25.7, 15.6-140; Cu 2.7-4.9, 3.3-15; Co 12.6-14.6, 8.8-10.4; Ni 2.5-75.1, 41.5-69.7; Cr 2.2-3.12, 2.32-4.82; Cd <0.34, 0.45-2.54; Pb 2.1-5.3, 0.8-3.8. Comparison between levels of metals in the imported and Ethiopian rice showed significant differences for most of the metals. The results indicated that Ethiopian rice is comparatively rich in essential metals than imported one. A statistical analysis of variance (ANOVA) at 95% confidence level for metal determination indicated significant difference between the means of each variety of samples. Comparison between levels of metals in cooked and raw rice showed that the difference in the level is not significant. [ABSTRACT FROM AUTHOR]

White lupin (Lupinus albus L.) cultivated in Ethiopia is locally known as 'Gibto'. Its seed is used as a snack, for the preparation of local alcoholic drink, 'Areqi' and as 'Shiro' flour for the people living in the north western part of Ethiopia. It is also used for maintaining soil fertility and as a food. Certain elements are essential for plant growth, for animal and human health. However, if present in excessive concentrations they become toxic. Other elements are non-essential and toxic to human health even at trace level. Even though the levels of four of the elements are reported, there is no report in literature on the levels of other essential and non-essential elements in white lupin cultivated in Ethiopia. Therefore, this study was carried out to determine the levels of essential (K, Na, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn) and non-essential elements (Pb and Cd) in raw and processed grains Lupinus albus L. (Gibto) cultivated in Ethiopia (particularly Debretabor, Dembecha and Kosober). The micro and macro-nutrient levels of the raw and processed white lupin grains were determined by flame atomic absorption spectrometry. Known weight of dried raw and processed samples were wet digested using 2 mL of HNO3, 1 mL of HClO4 and 1 mL of H2O2 at temperature round 270 °C with 3 hours total time. The mean metal concentration (μg/g dry weight basis) ranges in raw and processed white lupin samples, respectively, were: K (5142-6215, 1100-1222), Na (31.9-50.1, 15.1-31.1), Mg (1739-2159, 629-759), Ca (502-967, 709-1284), Cr (11.3-17.6, 9.40-10.3), Mn (1657-4095, 1075-2265), Fe (77.9-92.8, 70.7-83.8), Co (16.2-16.6, 16.7-17.2), Ni (12.0-15.6, 6.90-11.7), Cu (4.80-9.90, 5.10-12.2), Zn (40.3-53.6, 55.6-64.6) and Pb (10.8-16.4, 9.90-13.1). The level of Cd was below method detection limit in both the raw and processed samples from all the sample sites. The concentrations of all the nutrients were higher in raw as compared to processed white lupin samples except for Ca, Co, Cu and Zn samples from all of the sampling sites. Analysis of variance (ANOVA) at 95% confidence level indicated that there is significant difference between the mineral contents of raw and processed samples from the three sample sites. Pearson correlation indicated positive correlation between most elements in both the raw and processed samples. In general, white lupin is rich in essential elements and safe to consume and could be an alternative source of the essential elements to the individual daily intake. [ABSTRACT FROM AUTHOR]

The ability of waste residue, generated from alum manufacturing process, to remove fluoride ion from water has been investigated. Series of batch adsorption experiments were carried out to assess parameters that influence the adsorption process. The factors investigated include the effect of contact time, adsorbent dose, thermal pretreatment of the adsorbent, neutralization of the adsorbent, initial fluoride concentration, pH of the solution and effect of co-existing anions. Results showed that Adsorption of fluoride is fairly rapid in first 5min and thereafter increases slowly to reach the equilibrium in about 1h. The removal efficiency of fluoride was increased with adsorbent dosage. About 85% removal efficiency was obtained within 1h at an optimum adsorbent dose of 16g/L for initial fluoride concentration of 10mg/L. Heat treatment and surface neutralization of the adsorbent did not improve the fluoride removal capacity and efficiency. The amount of fluoride adsorbed increased with increasing initial fluoride concentration. The percentage of fluoride removal remains nearly constant within the pH range of 3-8. The adsorption data at ambient pH were well fitted to the Dubinin-Radushkevick (D-R) isotherm model with a capacity of 332.5mg/g of the adsorbent. The adsorption kinetic was found to follow a pseudo-second-order rate equation with an average rate constant of 2.25gmin(-1)mg(-1). The presence of bicarbonate at higher concentrations (100-500mg/L) decreased the fluoride removal efficiency while other anions (chloride, sulfate, phosphate and nitrate) have no significant effect within the concentration range tested. The overall result shows that the waste residue is efficient defluoridating material.