Covenant Journal of Physical and Life Sciences

Antidiabetic Potential of Biosynthesized Silver Nanoparticles with Fresh Guava Leaf

2025-03-31T14:32:57+00:00

Current diabetes medications have been associated with varying degrees of adverse effects and prolonged toxicity, further complicating morbidity and mortality. This necessitates the search for less toxic alternatives, such as nanoparticles. Hence, this research aimed to assess the hypoglycemic capabilities of biosynthesized silver nanoparticles (AgNPs) with fresh guava leaves. Twenty-five (25) albino Wistar rats weighing 120-230 g were obtained and allowed to acclimatize for 7 days in a well-ventilated room with a standard temperature of 29 ºC, relative humidity of 70%, and a 12:12-hour photoperiod. The experimental rats were fed food and water as appropriate and were divided into five (5) groups. Group I: (NC) non-diabetic rats, given water (reconstitution solvent); Group II: (DC) non-treated diabetic rats, given distil water; Group III: (MET) Standard control: diabetic rats administered 200 mg/kg BW Metformin; Group IV: treated animals given AgNPs and guava leaves, regular feed, and water, and Group V: treated with guava extract and induced intraperitoneally with STZ at 60 mg/kg for 48hrs to induce diabetes before treatment. The dose regimens were administered once per day for twenty-one (21) days. The results obtained revealed a significant increase (p<0.05) in mean plasma glucose relative to diabetic control groups and a substantial increase (p<0.05) in mean serum insulin when compared to diabetic control groups. Mean plasma glucose in albino Wistar rats in Table 1 displayed a significant decrease in glucose levels of rats administered AgNPs from day 1 to 14 at p<0.05. Additionally, serum insulin was significantly elevated in the AgNPs group when compared to the Metformin group at p<0.05, and this was also seen in the experimental group administered guava leaf extracts. Essentially, silver nanoparticles and guava extract showed antidiabetic activity by reducing glucose levels and synergistically enhancing the production of beta cells for glucose uptake to peripheral tissues.

Stability and optimal measures analysis on the transmission dynamics of Tuberculosis by means of fractional order

2025-05-13T16:07:37+00:00

While being a treatable and preventable disease, tuberculosis (TB) nonetheless poses a serious global health threat and claims millions of lives each year. In this study, a sophisticated mathematical technique from fractional calculus theory is used to explore the complex dynamics of tuberculosis transmission. To capture the subtle progression of tuberculosis infection, the study employs an SEIR model that categorizes the population into distinct compartments. The potential of fractional calculus to transform epidemiological research by simulating the dynamics of infectious diseases was demonstrated through its use. By leveraging the intrinsic flexibility and precision of fractional derivatives, we enhance our understanding of tuberculosis epidemiology and establish the foundation for innovative methods in disease control and prevention. The intricate interactions between susceptible, vaccinated, latent, treated, acute, and recovered individuals in the population were discussed using careful analysis and numerical simulations. The efficiency of several control tactics, including vaccination, treatment of latent and current cases and preventive measures is clarified by key findings from the study. How these interventions affect the dynamics of tuberculosis transmission, community immunity, and disease burden was clarified. In addition, the study provides important information for public health practitioners and policymakers highlighting the varying effectiveness of control methods in reducing transmission and increasing recovery rates. Also, the study is a step forward in epidemiology, providing a comprehensive understanding of the dynamics of TB transmission and the effectiveness of control measures using fractional derivatives. The results of this study are expected to be a guide for evidence-based initiatives, ultimately buttressing international efforts to fight tuberculosis and enhance public health.

Investigating the mixture of a benzotriazole and potassium iodide as efficient inhibitor against acid corrosion of 70Cu–30Ni alloy

2025-05-28T14:37:43+00:00

Industrial heat exchangers and cooling systems usually develop scales on their internal walls, which impede fluid flow, diminish their thermal conductivities and, hence, their efficiencies. Restoring these qualities requires pickling with acid solutions, especially, HCl which forms very soluble products of scales. Without adding efficient corrosion inhibitor chemicals to the pickling solutions, serious corrosion attack on the substrates accompanies the acid pickling process. Identifying prospective corrosion inhibitor chemicals with green environmental profile and high efficiencies becomes imperative for many industries. Herein, we employed weight loss, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) to investigate the mixture of 5–methyl–1H–benzotriazole (5MB) and potassium iodide (KI) as efficient corrosion inhibitor systems for heat exchanger-type alloy (70Cu-30Ni) against corrosion in 1 M HCl solution. The addition of KI boosts the inhibition efficiency of 5MB from ≈74 % to ≈96 %. The 5MB + KI mixture impacts a strong anodic shift in corrosion potential (E_corr) and boosts the passivation of the alloy. The inhibitor mixture is also very efficient to diminish the extent of surface microstructural degradation of the alloy, based on characterizations by atomic force microscopy (AFM) and scanning electron microscopy (SEM).

Stabilization and Environmental Sustainability of Swelling Clays Soils: A Review

2025-07-22T17:10:30+00:00

Water movement in swelling soils conforms with material continuity. This invariably justifies the differences in the gravitational potential energy during expansion and the anisotropic stresses that press the soil but allow for vertical movement. Under fluid conditions, vane efficiency exhibited by macropores is lowered by swelling of the clay, and a poorly drained soil results in surface saturation. The type of water applied to soil material tends to have an impact on the positioning of cracks in swelling clays, and thus, cracks can remain pathways for preferential flow much after they are covered at the soil surface. Over time, chemicals and chemical compounds have been utilized to further enhance the engineering properties of such soils. However, environmentally friendly biodegradable biological stabilizers are taking the place of conventional stabilizers, most especially lime and cement. Additionally, biochar amendment, which is ecofriendly, has also been found to lower the swelling index capability of expansive clay soil. Despite the dangers associated with swelling clay, it has found extensive use as adsorbents, carriers in drug delivery systems, and the building of a storage tank for the disposal of radioactive materials. In addition, swelling clays have found significant usage in the production of controlled-release fertilizers (CRFs) formulations. Hence this paper emphasizes the environmental impact of building large structures and road construction on swelling clay soils, highlights recent progress in the inhibition and stabilization of swelling soils to sustain the environment, and enumerates the economic importance associated with swelling clay soils.

Comparative Biochemical Characterization of Hydrocarbon-Degrading Bacteria on Petroleum-Contaminated Soils from Baranyonwa-Dere in Gokana and Non-Contaminated Soils from Rukpokwu in Obio/Akpor L.G.A, Rivers State, Nigeria

2025-11-07T15:46:12+00:00

This study presents a comparative biochemical evaluation of hydrocarbon-degrading bacteria (HDB) isolated from petroleum
contaminated soil in Baranyonwa-Dere (B-Dere), Gokana LGA, and non-contaminated soil from Rukpokwu, Obio/Akpor LGA, Rivers
State, Nigeria. Using culture-dependent methods and standard biochemical assays, five bacterial genera were identified across both sites: Pseudomonas sp., Salmonella sp., Citrobacter sp., Bacillus megaterium, and Bacillus subtilis. However, isolates from the contaminated site demonstrated significantly higher enzymatic activities, including catalase, urease, succinate dehydrogenase, peroxidase, and protease. Among the isolates, Bacillus subtilis from the polluted soil exhibited the highest catalase (730.73 ± 79.92 µmol/mL/min) and urease (0.25 ± 0.01 mg/g/min) activities, while Pseudomonas sp. recorded peak succinate dehydrogenase activity (5.67 ± 0.01 µmol/mL/min). Bacillus megaterium excelled in peroxidase (76.04 ± 0.01 µmol/mL/min) and protease (91.08 ± 0.68 units/mg) activities. In contrast, isolates from the non-contaminated site exhibited comparatively lower enzymatic expression, indicating reduced metabolic demand and hydrocarbon stress. Catalase activity was significantly dominant (p < 0.001) in the polluted environment, suggesting its pivotal role in microbial oxidative stress management and survival in petroleum-rich soils. These findings confirm that oil contamination selectively enhances the diversity and enzymatic adaptation of indigenous bacteria, equipping them for effective hydrocarbon degradation. The elevated metabolic activities in contaminated soils underscore the potential of these native strains as viable bioremediation agents. Harnessing their enzymatic profiles offers a sustainable and eco-friendly strategy for restoring oil-polluted environments in the Niger Delta and similar regions globally.