Tax Revenue and Economic Growth: a Study of Nigeria and Ghana

Tax revenue is frequently considered as an alternative form of sustainable financing within a stable and predictable fiscal environment to promote growth and enable governments to finance their social and infrastructural needs. The objective of the study is to examine the effect of tax revenue on economic growth of Nigeria and Ghana. The study used multiple regressions as tools of analysis. The study finds a positive impact of tax revenue on the gross domestic product of Nigeria and Ghana confirming prior studies. The study recommended among others that adequate measure to ensure that revenue generated from the tax is effectively utilized to develop and grow the economy.DOI: 10.15408/sjie.v7i2.734

Biogas Generation from Co-Digestion Waste Systems: The Role of Water Hyacinth

Using biomass as a renewable energy source has earned tremendous interest from researchers in recent decades, especially because the technology is environmentally benign. This article reviews the recent methods for generating biogas from water hyacinth (WH, Eichornia crassipes), arguably the world’s most evasive aquatic macrophyte. Therefore, various economic, environmentally benign, and renewable procedures that enhance biogas production from WH biomass are reviewed. WH has been co-digested with numerous waste types, including poultry droppings, municipal wastes, animal tissue wastes, pig wastes, cow dungs, etc., recording varying success degrees. Other studies focused on optimizing the operation parameters, such as mixing ratio, contact time, pH, temperature, organic loading rate, etc. We observed that most attempts to generate biogas from WH alone were not promising. However, when co-digested with other biomasses or wastes, WH either increases the process rate or improves the methane yield content. Also, the potential of WH as a phytoremdiator-cum-biogas source was investigated. This chapter provides mathematical models, scale-up installation models, and specific experimental results from various studies to guide future study plans toward optimizing CH4 generation from WH co-digestion

Acalypha wilkesiana ‘Java white’: Identification of some bioactive compounds by GC-MS and their effects on key enzymes linked to type 2 diabetes

In this study, we identified bioactive compounds from the ethanolic extracts of the leaves, stem bark and root bark of Acalypha wilkesiana through GC-MS analysis and investigated the effects of these extracts on some of the enzymes linked to type 2 diabetes. Plant parts were extracted sequentially with ethyl acetate, ethanol and water. GC-MS analysis revealed the presence of long-chain alkyl acids, esters, ketones and alcohols including phytol and phytol acetate along with some secondary metabolites such as xanthone, vitamin E and various types of sterols including stigmasterol, campesterol and sitosterol. Ethanolic extracts of all the parts showed a dose-dependent inhibition of α-glucosidase and α-amylase activity. The extracts also demonstrated anti-lipase activity. The ethanolic extract of root bark showed the highest inhibition of enzymes compared to other extracts. The EC50 values (concentrations for 50 % inhibition) of α-glucosidase, α-amylase and lipase inhibition were 35.75 ± 1.95, 6.25 ± 1.05 and 101.33 ± 5.21 µg mL–1, resp. The study suggests that A. wilkesiana ethanolic extracts have the ability to inhibit the activity of enzymes linked to type 2 diabetes. Further studies are needed to confirm the responsible bioactive compounds in this regard

Short-Term Feeding of Fibre-Enriched Biscuits: Protective Effect against Hepatotoxicity in Diabetic Rats

The effects of fibre-enriched biscuit on biomarkers associated with hepatotoxicity in diabetic rats were investigated. Diabetes was induced by single intraperitoneal injection of alloxan monohydrate. Treatment lasted for 14 days after which the rats were sacrificed by cervical dislocation. Blood serum was analyzed to determine hepatic function enzymes. The liver was also analyzed to determine hepatic lipid profile and antioxidant enzymes. Induction of diabetes led to elevated levels of ALP, AST, and ALT. These were, however, significantly (p<0.05) reduced in the fibre-enriched biscuit fed (treated) group. There was no significant difference in the serum bilirubin and total protein levels of the studied groups. Reduced albumin level was observed in the diabetic group; this was further lowered on feeding with fibre-enriched biscuits. Induction of diabetes led to increased hepatic level of cholesterol, triglyceride (TG), low density lipoprotein (LDL), and lipid peroxidation and decreased activities of glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) and HDL level. These were significantly (p<0.05) reversed on feeding with fibre-enriched biscuit. This study portrays the protective effect of fibre-enriched biscuit on increased oxidative stress and hyperlipidemia in hepatic tissues of alloxan-induced diabetic rats

Water Quality Index for measuring drinking water quality in rural Bangladesh: a cross-sectional study

BACKGROUND: Public health is at risk due to chemical contaminants in drinking water which may have immediate health consequences. Drinking water sources are susceptible to pollutants depending on geological conditions and agricultural, industrial, and other man-made activities. Ensuring the safety of drinking water is, therefore, a growing problem. To assess drinking water quality, we measured multiple chemical parameters in drinking water samples from across Bangladesh with the aim of improving public health interventions. METHODS: In this cross-sectional study conducted in 24 randomly selected upazilas, arsenic was measured in drinking water in the field using an arsenic testing kit and a sub-sample was validated in the laboratory. Water samples were collected to test water pH in the laboratory as well as a sub-sample of collected drinking water was tested for water pH using a portable pH meter. For laboratory testing of other chemical parameters, iron, manganese, and salinity, drinking water samples were collected from 12 out of 24 upazilas. RESULTS: Drinking water at sample sites was slightly alkaline (pH 7.4 ± 0.4) but within acceptable limits. Manganese concentrations varied from 0.1 to 5.5 mg/L with a median value of 0.2 mg/L. The median iron concentrations in water exceeded WHO standards (0.3 mg/L) at most of the sample sites and exceeded Bangladesh standards (1.0 mg/L) at a few sample sites. Salinity was relatively higher in coastal districts. After laboratory confirmation, arsenic concentrations were found higher in Shibchar (Madaripur) and Alfadanga (Faridpur) compared to other sample sites exceeding WHO standard (0.01 mg/L). Of the total sampling sites, 33 % had good-quality water for drinking based on the Water Quality Index (WQI). However, the majority of the households (67 %) used poor-quality drinking water. CONCLUSIONS: Higher values of iron, manganese, and arsenic reduced drinking water quality. Awareness raising on chemical contents in drinking water at household level is required to improve public health

Peperomia pellucida in diets modulates hyperglyceamia, oxidative stress and dyslipidemia in diabetic rats

Objective: To investigate the antidiabetic and antioxidant properties of Peperomia pellucida (P. pellucida) in alloxan-induced diabetic rats. Methods: Beside mouse chow, two diets were designed to contain 10%w/w and 20%w/w P. pellucida as supplements respectively. Diabetes was induced in groups of five male albino rats by a single intraperitoneal injection of alloxan. Two groups of diabetic rats and normo rats were each fed one of these diets respectively, while two other groups served as positive and negative controls respectively. A seventh group was fed pelletized mouse chow. Results: Diabetic rats on diets supplemented with 10%w/w and 20%w/w of P. pellucida for 28 d resulted in reduction of blood glucose level. The level of total serum cholesterol, triglycerides and LDL-cholesterol decreased significantly (P<0.05) with the supplementation diets compared to the untreated diabetic rats. Also treatment with glibenclamide and P. pellucida (10% and 20%w/w) led to increased activities of SOD, CAT and GSH respectively. There was significant (P<0.05) reduction in the level of HDL-cholesterol, Catalase, SOD activities and GSH concentration in diabetic untreated rats. The supplemented diets significantly (P<0.05) reduced lipid peroxidation, which was elevated in untreated diabetic rats. Significant decrease (P<0.05) in the activities of AST, ALT and ALP was also observed in rats fed P. pellucida supplemented diets. Conclusions: The results from this study indicate that P. pellucida has an antidiabetic and antioxidant properties in experimental diabetes mellitus and thus justifies the acclaimed traditional antidiabetic use

Artesunate-induced testicular injury: Oil from selected spices blend modulates redox homeostasis and exacerbates steroidogenesis in rat models

The therapeutic potential of oil from blends of selected culinary spices against artesunate-induced testicular injury in albino rats was investigated. Two groups of rats each were pretreated with the oil at 1.5 and 3.00 mL respectively for seven days and after which administered artesunate (100 mg/kg bw) for seven days; two other groups were administered artesunate for seven days and after which post treated with the oil at both doses respectively for another seven days; another groups were co-administered artesunate and the oil for seven days. A group was administered artesunate only for seven days, while another was fed chows only. After sacrifice, the testicular homogenates of the rats were analysed for GSH, Superoxide Dismutase (SOD), Catalase (CAT), Lipid peroxidation (LPO), 3β-HSD and 17β-HSD activities. LPO and GSH levels, SOD and CAT activities were significantly (p < 0.05) higher in rats administered artesunate only, these were significantly lowered in all treatment groups. Administration of artesunate significantly suppressed steroidogenesis, this was attenuated in all treatment groups. The antioxidant, anti-lipid peroxidative and steriodogenetic effects of the oil indicate its protective potential against artesunate-induced oxidative testicular damage

Comparative effects of xylitol and erythritol on modulating blood glucose; inducing insulin secretion; reducing dyslipidemia and redox imbalance in a type 2 diabetes rat model

Xylitol and erythritol have been reported in numerous previous and recent studies as potential antidiabetic sweeteners, however, it is not certain which one is most effective in this regard. In the present study, the effects of xylitol and erythritol were comparatively investigated on blood glucose, insulin level, dyslipidemia, pancreatic islet morphology and β-cell function, and redox imbalance in a type 2 diabetes (T2D) model of rats. Seven-week-old male Sprague-Dawley rats were randomly divided into 8 groups: Normal Control (NC), Diabetic Control (DC), Diabetic Xylitol 5 % (DX5), Diabetic Xylitol 10 % (DX10), Diabetic Xylitol 20 % (DX20), Diabetic Erythritol 5 % (DE5), Diabetic Erythritol 10 % (DE10), and Diabetic Erythritol 20 % (DE20). T2D was induced in the diabetic groups initially by feeding 10 % fructose solution to induce insulin resistance followed by an intraperitoneal injection of streptozotocin (40 mg/kg body weight) dissolved in citrate buffer (pH 4.5) to induce partial pancreatic β-cells dysfunctions. The animals in NC group were fed with normal drinking water and injected with citrate buffer only. After the confirmation of diabetes, the xylitol and erythritol with above-mentioned concentrations were supplied to the respective animal groups when the animals in NC and DC groups were supplied with normal drinking water. After 8 weeks intervention period, the body weight, fluid and water intake, blood glucose, serum alanine aminotransferase, aspartate aminotransferase, CK-MB and creatinine were significantly decreased, while the serum insulin level, serum lipids, glucose tolerance ability, pancreatic islet morphology and β-cell function, pancreatic and serum redox imbalance were improved in the most xylitol and erythritol fed groups compared to the DC group, when effects were better for xylitol compared to erythritol. The data of this study suggest that xylitol has better antioxidant and antidiabetic effects compared to erythritol. Therefore, xylitol can be used as a preferrable dietary anti-diabetic sweetener or supplement over erythritol for the management of diabetes and its associated complications

Comparative alteration in atherogenic indices and hypocholesteremic effect of palm oil and palm oil mill effluent in normal albino rats

The comparative hypocholesteremic effect of feeding palm oil and palm oil mill effluent (POME) was investigated in male albino rats. Diets were prepared and designed to contain 50% of energy as carbohydrate, 35% as fat, and 15% as protein. Groups of six rats were each fed one of these diets, while a group was fed pelletized mouse chow which served as the control. Feeding on palm oil and POME led to a significant increase (p < 0.05) in serum total cholesterol, triglyceride, and vLDL. Feeding on POME led to significant increase (p < 0.05) in cholesterol, triglyceride and LDL levels in brain tissues. Increased hepatic LDL level was also observed in POME fed rats. Except for hepatic triglyceride and tissues HDL level, a rather reduced level of the studied lipids was observed in the serum and tissues of palm oil fed rats compared to POME. These results indicate the protective potentials of palm oil against cardiovascular disease, as well as hyperlipidemia that characterize obesity and hypertension; as compared to its effluent

Phytochemical Properties of <i>Croton gratissimus</i> Burch (Lavender Croton) Herbal Tea and Its Protective Effect against Iron-Induced Oxidative Hepatic Injury

Oxidative stress plays a vital role in the pathogenesis and progression of various liver diseases. Traditional medicinal herbs have been used worldwide for the treatment of chronic liver diseases due to their high phytochemical constituents. The present study investigated the phytochemical properties of Croton gratissimus (lavender croton) leaf herbal tea and its hepatoprotective effect on oxidative injury in Chang liver cells, using an in vitro and in silico approach. C. gratissimus herbal infusion was screened for total phenolic and total flavonoid contents as well as in vitro antioxidant capacity using ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picryl-hydrazyl (DPPH) methods. Oxidative hepatic injury was induced by incubating 0.007 M FeSO4 with Chang liver cells which has been initially incubated with or without different concentrations (15–240 μg/mL) of C. gratissimus infusion or the standard antioxidants (Gallic acid and ascorbic acid). C. gratissimus displayed significantly high scavenging activity and ferric reducing capacity following DPPH and FRAP assays, respectively. It had no cytotoxic effect on Chang liver cells. C. gratissimus also significantly elevated the level of hepatic reduced glutathione (GSH), superoxide dismutase (SOD), and catalase activities as well as suppressed the malondialdehyde (MDA) level in oxidative hepatic injury. Liquid Chromatography–Mass Spectrometry (LC-MS) analysis of the herbal tea revealed the presence of 8-prenylnaringenin, flavonol 3-O-D-galactoside, caffeine, spirasine I, hypericin, pheophorbide-a, and 4-methylumbelliferone glucuronide. In silico oral toxicity prediction of the identified phytochemicals revealed no potential hepatotoxicity. Molecular docking revealed potent molecular interactions of the phytochemicals with SOD and catalase. The results suggest the hepatoprotective and antioxidative potentials of C. gratissimus herbal tea against oxidative hepatic injury