Hydrometallurgical assessment of oxides of Nb, Ta, Th and U from Ethiopian tantalite ore.

Tantalite ore is the main source of the metals niobium (Nb) and tantalum (Ta). Today, the needs for these economic and irreplaceable Nb, and Ta metals are becoming imperative for the technological world, to meet the demand, a lot of research is needed to ore reserves, extraction methodology and simplified refining processes should be in plethora. This study focuses on the Ethiopian tantalite ore located south of the Neoproterozoic Adola belt of the rare element Kenticha pegmatite deposit (global source of tantalite). Successive beneficiation of pegmatite ore results in a highest dissolution of 60.83 wt% of Ta2O5 with 4.58 wt% of Nb2O5 including the removal of U, Th, Ti, Fe and Si, resulting in a percentage low weight, which allows transporting ore concentrates. The concentrated ore is leached with a mixture of binary acids HF and H2SO4 with 6:1 ratio at temperatures from 100 to 400 °C. The filtered solution was extracted with MIBK then, precipitated with ammonium solution. The hydrometallurgy of Nb and Ta oxides is affected by leaching temperature and the presence of radioactive oxides of U and Th. Elemental analysis and surface topography were studied using SEM/EDS, revealing the highest percentage composition of Nb and Ta oxides at 200 °C of leaching temperature. Comparatively, the compositions of U and Th showed higher amounts at the leaching temperatures of 150 and 200 °C, and when the temperature reached about 350 and 400 °C, the percentage composition of U and Th became very low, the economic metals Nb and Ta were completely leached. The stability of the precipitated samples was analyzed using TGA-DTA and found to be thermally stable, and not contain significant moisture at each temperature studied. Studies for recovery of Ta, Nb, U and Th from Kenticha tantalite are required.

Phytochemical Constituents of Adansonia digitata L. (Baobab) Fruit Pulp from Tekeze Valley, Tigrai, Ethiopia.

Baobab (Adansonia digitata L) is a large tree species growing in semiarid and arid lowlands of Ethiopia and other places. The plant is valued by natives for its contributions as a cash crop and livelihood tree. Previous studies using samples from different countries have documented their phytochemical profiles and nutritional and health benefits. This study explored the phytochemical constituents and biological activities of fruit pulp extracts of baobab collected from Tekeze Valley, Tigrai, Ethiopia. To this end, qualitative phytochemical screening tests, quantitative phytochemical analyses, and gas chromatography-mass spectrometry (GC-MS) analysis were carried out using aqueous extract. Analyses of antioxidant activities were also conducted with aqueous- and methanol-extracts using of 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), and hydroxyl (OH) radical scavenging activity assays. The qualitative screening tests showed the presence of flavonoids, phenols, saponins, tannins, and terpenoids. Quantitative analyses of these phytochemicals at 25, 50, and 100 g/mL aqueous extract resulted in 0.0252 to 0.1000% yields. Yields of flavonoids, phenols, and saponins were higher at 50 g/mL extract, while that of tannins and terpenoids were higher at 100 g/mL. GC-MS analysis resulted in 15 predominant compounds including (1,2bis(trimethylsilyl)benzene (13.17%), 2-methyl-7-phenylindole (11.75%), 2-ethylacridine (10.11%), and benz[b]-1,4-oxazepine-4(5H)-thione,2,3-dihydro-2,8-dimethyl (10.11%). Aqueous and methanol extracts showed concentration-dependent antioxidant activities. In all the assays and concentrations, the antioxidant activities of both extracts were lower than that of the ascorbic acid standard. At equal extract concentrations (e.g., 100 and 250 µg/mL), methanol extract had higher antioxidant activities than aqueous extract. The findings can encourage future initiatives towards large-scale research for compiling a complete phytochemical profile of the fruit pulp of the Ethiopian baobab.

Aloe adigratana Reynolds: Preliminary Phytochemical Screening, Proximate Content, Essential Oil Analysis, and In Vitro Antifungal Activity Studies of Its Leaf Peels and Gel.

Background: Aloe species are among the most significant plants with several applications. Many of the species, however, are underexplored, owing to their scarcity and limited geographical distribution. A. adigratana Reynolds, which is common in Ethiopia, is one of the little-studied and endangered Aloe species. Objective: This preliminary study focuses on the phytochemical screening, proximate analysis, essential oil content, and antifungal activities of A. adigratana leaf peels. Antifungal activities were also tested on the gels of the plant for comparison. Methods: Standard procedures were used for phytochemical and proximate composition studies. Essential oil analysis was performed using a gas chromatography-mass spectrometry instrument. Using the well-diffusion method, investigations on antifungal activity were performed on three clinically isolated specimens of dandruff-causing fungus; namely, Malassezia furfur, Malassezia restricta, and Malassezia globosa. Results: The leaf peels of A. adigratana contained alkaloids, flavonoids, tannins, and terpenes. The mean moisture, ash, and crude fat levels were 85.69, 92.20, and 8.00%, respectively, whereas the mean total protein and mean total carbohydrate values were 2.59 and 3.04%. Gas chromatography-mass spectrometry investigation confirmed the presence of fifteen essential oils. The most prevalent essential oil component was discovered to be phytol (33.78%), followed by decane (11.29%). In a dose-dependent way, the leaf latex and gel extracts prevented the growth of three dandruff-causing Malassezia fungal species (M. furfur, M. restricta, and M. globosa). Both the latex and gel demonstrated the maximum activity on M. globosa, the most prevalent fungus in the research area, with minimum inhibitory concentrations of 0.24 and 0.48 mg/mL and minimum fungicidal concentrations of 0.48 and 0.97 mg/mL, respectively. Conclusion: In general, the proximate and essential oil compositions of A. adigratana leaves were comparable to those of other Aloe species widely used in the food, cosmetic, and pharmaceutical industries, implying that A. adigratana could be a potential future plant for such industries.

Formulating the best Helbat: A Tigraian semi-liquid fasting condiment.

Helbat (hl'bət), a fasting semi-liquid condiment, is a popular indigenous traditional fermented product in Tigrai (a.k.a. Tigray), Ethiopia. It is formulated using Vicia faba flour prepared from mildly roasted dry beans. Despite its dietary, nutritional, religious, and cultural significance, the condiment is yet not exposed to scientific study. Hence, this research was carried out to: (a) ascertain the best faba bean variety for preparing high quality Helbat, (b) develop the formulation and preparation protocol of high quality Helbat, (c) determine the effects of fermentation and storage temperature and time on the physicochemical characteristics, proximate and mineral compositions, microbiological properties, and sensory qualities of Helbat, and (d) determine the shelf life of Helbat as the function of storage time and temperature. To this end, three faba bean varieties used in preparing Helbat as well as fermenting and stored Helbat products were studied using standard physicochemical, microbiological, and sensory evaluation procedures. Quantitative data were processed using inferential statistical methods and mean (±SD) values were compared at a priori set p-value of ≤0.05. The study showed that: (a) the best faba bean variety for making high quality Helbat was Megulat; (b) the best Helbat formulation constituted 400 wt units of bean flour, 7 wt units of garlic, 6 wt units of ginger, 5 wt units fenugreek, 5 wt units of corrorima, 8 wt units of red pepper, and 3 wt units of black mustard; (c) the best Helbat formulation was nutritionally rich to supplement fasting consumers with proteins, fats, and minerals; (d) the Helbat formulation remained safe for up to eight weeks while maintaining its attractive sensory qualities when stored at 11-15 °C, and (e) increasing the fermentation and storage times led to changes in its physicochemical properties (i.e., temperature, pH, total titratable acidity, and total soluble solute) and depletion of many nutritionally vital components such as fats, proteins, and minerals. Thus, unless production and storage conditions are somehow modified, Helbat needs to be consumed fresh after three to seven days of fermentation. But further research may be required to make this recommendation conclusively. Exploring into its antioxidant properties and lactic acid bacteria (LAB) may highlight its qualities further.

Assessment of Some Physicochemical Parameters and Heavy Metals in Hand-Dug Well Water Samples of Kafta Humera Woreda, Tigray, Ethiopia.

Groundwater is one of the most important sources of drinking water in Kafta Humera Woreda; hence, it is important to assess the quality of these water sources. The aim of this study was to assess the levels of some physicochemical parameters and heavy metals in hand-dug well water sources of Kafta Humera Woreda. The results showed that the physicochemical concentrations of the hand-dug well water samples were given as follows: temperature, 27.67 ± 0.15 to 28.30 ± 0.25°C; pH, 6.90 ± 0.33 to 8.20 ± 0.36; dissolved oxygen, 5.60 ± 0.06 to 6.2 ± 0.04 mg/L; turbidity, 1.67 ± 0.02 to 1.89 ± 0.03 NTU; EC, 148.50 ± 0.89 to 932.00 ± 0.98 µS/cm; TDS, 105.80 ± 0.62 to 664.28 ± 0.70 mg/L; total hardness, 71.80 ± 3.05 to 295.30 ± 2.38 mg/L; total alkalinity, 75 ± 5.0 to 215 ± 5.0 mg/L; calcium, 12.02 ± 0.82 to 75.88 ± 0.93 mg/L; magnesium, 9.80 ± 0.80 to 25.70 ± 0.17 mg/L; potassium, 0.130 ± 0.003 to 0.86 ± 0.04 mg/L; sodium, 2.20 ± 0.16 to 12.75 ± 0.87 mg/L; chloride, 12.86 ± 0.02 to 42.72 ± 0.20 mg/L; sulfate, 17.24 ± 0.96 to 118.67 ± 0.46 mg/L; phosphate, 0.018 ± 0.005 to 0.020 ± 0.002 mg/L; and nitrate, 1.86 ± 0.03 to 5.43 ± 0.06 mg/L. Generally, the concentrations of most physicochemical parameters of the hand-dug well water samples of Kafta Humera Woreda were within the permissible limit of World Health Organization and Ethiopian Standard Agency guideline for drinking water. The statistical Pearson's correlation analysis on the water quality parameters revealed that all parameters are more or less correlated with each other. Electrical conductivity and total dissolved solids of the water samples were found to be significantly correlated with total hardness (r = 0.989), total alkalinity (r = 0.827), calcium (r = 0.988), magnesium (r = 0.881), sodium (r = 0.995), potassium(r = 0.996), chloride (r = 0.998), sulfate (r = 1), and nitrate ions (r = 0.972). Out of the selected seven heavy metals, Fe, Cu, Zn, Mn, Cr, Cd, and Pb, only iron was detected in all water samples and its concentration was above the permissible limit of WHO and ESA for drinking water. Therefore, the government should adopt some treatment technologies such as sedimentation and aeration to minimize the concentration of iron for safe drinking the water to the community of Kafta Humera Woreda.

Hair Washing Formulations from Aloe elegans Todaro Gel: The Potential for Making Hair Shampoo.

This study aimed to describe the gross phytochemical constituents of Aloe elegans Todaro gel and evaluate the characteristics and quality of lab-made hair washing formulations prepared from the gel to show its potential in formulating hair washing shampoos. A. elegans gel mass was prepared from mature, healthy leaves collected from natural stand. Samples of 100% methanol extract of the gel were subjected to standard phytochemical screening and gas chromatography-mass spectroscopy (GC-MS) analysis. Five hair washing formulations (Fs) were, likewise, prepared by mixing 4.0-10.0 mL of gel with one (0.05 mL) to two (0.10 mL) drops of six synthetic and natural ingredients, namely, coconut oil, jojoba oil, olive oil, pure glycerin oil, lemon juice, and vitamin E. The gel to the total ingredient ratios (v/v) of the five formulations were 93 : 7 (F1), 94.5 : 5.5 (F2), 96.4 : 3.6 (F3), and 96.6 : 3.4 (F4 and F5). The formulations were evaluated using sensory inspection and common physicochemical methods. The phytochemical screening and GC-MS analysis revealed that A. elegans gel is the source of important chemical constituents used in the formulation of shampoos and similar products including saponins, capric acid, lauric acid, myristic acid, palmitic acid, linoleic acid, stearic acid, and phytol. Lab-made A. elegans hair washing formulations, especially those with 96.4-96.6% gel, were found to have similar characteristics and qualities with a common marketed shampoo. All the formulations were turbid with characteristic odor as the marketed shampoo. The pH values of the hair washing formulations (6.4-4.6) were comparable to those of the marketed shampoo (6.7). Formulations with higher proportion of gel had better foam stability, higher solid content (26-29%), higher surface tension (33-38 dynes/cm), shorter wetting time (150-160 sec), equivalent viscosities (26.45-26.73 poise), and conditioning performance than the marketed shampoo. These findings demonstrate that A. elegans gel mass can be used in the formulation of good-quality hair washing shampoos. We recommend future studies that aim to develop the phytochemical profile of the plant and a refined protocol of hair washing shampoo formulation.

Formulation and Physicochemical Evaluation of Lab-Based Aloe adigratana Reynolds Shampoos.

Aloe L. species (Aloaceae) are ethnobotanically very valuable plants in many communities and civilizations. Nonetheless, very few species are extensively studied to explore their applications in the pharmaceutical and medical, cosmetic and personal care, food and beverage, and detergent industries. This study evaluated the characteristics and quality of lab-based shampoos formulated from the gel of Aloe adigratana Reynolds. Five shampoo formulations, 20 mL each, were prepared from A. adigratana gel in combination with one to two drops of coconut oil, jojoba oil, olive oil, pure glycerin oil, lemon juice, and vitamin E. Gel mass is prepared from mature, healthy leaves collected from the natural stand. The phytochemistry of the gel of the plant was also studied using phytochemical screening, proximate composition, and GC-MS analysis studies. Shampoo formulations with higher proportion (40 to 50% v/v) of A. adigratana gel were found to have comparable characteristics and qualities with a marketed shampoo. They fall within the range of acceptable quality parameters of commercial shampoos. The phytochemical studies of A. adigratana gel showed that the plant is the source of highly valued compounds for the preparation of shampoos. The gel was found to be rich in saponins as well as dodecanoic acid, hexadecanoic acid, and phytol. Future works should focus in the development of refined protocol towards formulating A. adigratana-based shampoos.