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±0.04mg/L; turbidity, 1.67±0.02 to 1.89±0.03 NTU; EC, 148.50±0.89 to 932.00±0.98μS/cm; TDS, 105.80±0.62 to 664.28±0.70mg/L; total hardness, 71.80±3.05 to 295.30±2.38mg/L; total alkalinity, 75±5.0 to 215±5.0mg/L; calcium, 12.02±0.82 to 75.88±0.93mg/L; magnesium, 9.80±0.80 to 25.70±0.17mg/L; potassium, 0.130±0.003 to 0.86±0.04mg/L; sodium, 2.20±0.16 to 12.75±0.87mg/L; chloride, 12.86±0.02 to 42.72±0.20mg/L; sulfate, 17.24±0.96 to 118.67±0.46mg/L; phosphate, 0.018±0.005 to 0.020±0.002mg/L; and nitrate, 1.86±0.03 to 5.43±0.06mg/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 Pearsons 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.

Briquetted biomass, like sugarcane bagasse, a by-product of sugar mills, is a renewable energy source. This study aimed at the production and characterization of bagasse briquettes. The production of briquettes was carried out with different blending ratios (5, 10, and 15%) and average particle sizes (0.75, 2.775, and 4.8 mm) with various binders of cow dung, waste paper, and admixture (molasses and wastepaper). The bagasse underwent drying, size reduction, sieving, binder addition, and densification using a manual press during the briquetting process. Characterization of the physical and combustion parameters of briquettes, such as density, shatter resistance, proximate, and calorific value, followed the American Society for Testing and Materials procedures. The result shows that the maximum density of briquettes was 0.804 g/cm³, while shatter resistance varied from 83.051 to 94.975% (4.8mm, 5% cow dung and 0.75mm, 5% admixture binders respectively). ANOVA analysis showed that the factors and their interactions had a significant influence (p value < 0.05) on the physical properties. The optimum parameters of briquettes achieved were 14.953% admixture binder, 0.776 mm particle size, 0.805 g/cm³ density, and 95.811% shatter resistance. Bagasse briquettes with a 5% cow dung binder achieved a high calorific value of 39927.05 kcal/kg. The ultimate analysis revealed a composition of 47.49% carbon (C), 5.133% hydrogen (H), 1.557% nitrogen (N), 0.374% sulfur (S), and 45.446% oxygen (O). Therefore, bagasse has a high calorific value and can be used for briquetting to replace fossil fuel and firewood in different applications. In addition, due to its availability, utilizing as fuel source has economic advantage. Graphical abstract

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 100g/mL aqueous extract resulted in 0.0252 to 0.1000 yields. Yields of flavonoids, phenols, and saponins were higher at 50g/mL extract, while that of tannins and terpenoids were higher at 100g/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 250μg/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.

The applications of various clay minerals are related to their structural, physical, and chemical characteristics. These properties of the clay minerals dictate their utilization in the industries and beneficiation required before usage. The study aimed at establishing the potentiality of acid‐activated clay mineral from Hadar, Afar, Ethiopia. XRD, SEM, energy‐dispersive X‐ray fluorescence (EDXRF), and FT‐IR spectroscopies were employed to characterize the chemical compositions and interaction in the bentonite samples. The XRD results revealed that the native and activated bentonite clay contains similar minerals, such as montmorillonite (MMT) ([Ca, Na]_0.33 [Al, Mg]₂[Si₄O₁₀][OH]₂.nH₂O), quartz (SiO₂), albite (NaAl₂SiO₆), zeolite (CaAl₂O₃.SiO₂.nH₂O), and aluminum silicate. Thus, attributes of the bentonite clay was composed of SiO₂ and Al₂O₃ indicating that it is an aluminosilicate mineral, and the morphology of bentonite was supported by SEM. The chemical analysis by EDXRF revealed that the native bentonite (NB) consisting of 58.18 wt% (SiO₂), 14.28 wt% (Al₂O₃), and Na₂O > CaO are the major constituents of the clay with other oxides present in low amount. There was an increase in the SiO₂ content in activated bentonites, and the Al₂O₃, Fe₂O₃, and MgO contents have decreased by 48.56%, 66.36%, and 84.42%, respectively. The FT‐IR spectra bands at 1627 cm⁻¹ and 1027 cm⁻¹ were attributed to Al–Mg–OH, Al–Al–OH, and Al–OH–O–Si stretching vibration, and the reduction of the content of the octahedral cations is accompanied by a decrease of both OH bending vibrations at 1627 and 3401 cm⁻¹. The FT‐IR result is in clear agreement with the SEM, XRD, and EDXRF studies which indicate sequential degradation of the clay sheet upon acid treatment. Hence, rendering the activated bentonite clay of Hadar has accounted for their demand for different industrial applications such as its use as detoxifier, sealant, binder, fillers for paper, pharmaceutical products, absorbent, adsorbent, catalyst, and nanoclays.

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.