Papers by Melford C Egbujor (Ph.D)
Antioxidants, Mar 13, 2024
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Journal of biochemical and molecular toxicology, Feb 18, 2024
Central nervous system agents in medicinal chemistry, Apr 1, 2024
International Journal of Pharmaceutical and Phytopharmacological Research, Dec 31, 2022
Amino acids, Mar 20, 2024
Oxidative stress can affect the protein, lipids, and DNA of the cells and thus, play a crucial ro... more Oxidative stress can affect the protein, lipids, and DNA of the cells and thus, play a crucial role in several pathophysiological conditions. It has already been established that oxidative stress has a close association with inflammation via nuclear factor erythroid 2-related factor 2 (NRF2) signaling pathway. Amino acids are notably the building block of proteins and constitute the major class of nitrogen-containing natural products of medicinal importance. They exhibit a broad spectrum of biological activities, including the ability to activate NRF2, a transcription factor that regulates endogenous antioxidant responses. Moreover, amino acids may act as synergistic antioxidants as part of our dietary supplementations. This has aroused research interest in the NRF2-inducing activity of amino acids. Interestingly, amino acids' activation of NRF2-Kelch-like ECH-associated protein 1 (KEAP1) signaling pathway exerts therapeutic effects in several diseases. Therefore, the present review will discuss the relationship between different amino acids and activation of NRF2-KEAP1 signaling pathway pinning their anti-inflammatory and antioxidant properties. We also discussed amino acids formulations and their applications as therapeutics. This will broaden the prospect of the therapeutic applications of amino acids in a myriad of inflammation and oxidative stress-related diseases. This will provide an insight for designing and developing new chemical entities as NRF2 activators.
Zenodo (CERN European Organization for Nuclear Research), May 25, 2023
Corrosion is an electrochemical process that has constituted serious environmental problems to in... more Corrosion is an electrochemical process that has constituted serious environmental problems to industries, homes and other environment. Metals of various types and grades are widely used in industrial installations and are often exposed to some aggressive media including acid, base and salt. Due to the fact that various industrial installations made of metals such mild steel, aluminum, and zinc are susceptible to corrosion attack during acid wash, etching, scale removal, etc., acid corrosion of these metals has garnered greater consideration and research. Numerous inhibitors have apparently been researched and used to reduce the rate of corrosion of important metals in light of these and other impacts, with positive results. The majority of the typical corrosion inhibitors, however, are poisonous, expensive, non-biodegradable, and difficult to get, according to environmental and other issues. The combination of inhibitors to improve anti-corrosive activity through synergistic actions remains a very important strategy for combating corrosion of mild steel. In this work, we combinedchitosan (CT) and polyvinyl propenenitrile (PVP), and explored their anti-corrosive action on mild steel in acidic medium via weight loss method. Results obtained from the weight loss experiment indicated that, the instantaneous inhibition efficiencies of the mixture of CT and PVP were higher than their individual inhibition efficiencies. Results showed that the corrosion inhibition efficiencies of a mixture of CT and PVP (77.49469 %) was higher than the individual components of CT (64.25 %) and PVP (52.02 %) at 303K.
Journal of pharmaceutical research international, May 30, 2020
Aim: To systematically design, synthesize and evaluate the biological activities of new threonine... more Aim: To systematically design, synthesize and evaluate the biological activities of new threoninebased sulfonamide derivatives in order to achieve improved drug potency. Methodology: Sulfamoyl carboxylic acids were prepared by the reaction of threonine with the appropriate sulfonyl chloride while their acetylated, carboxamide and aniline derivatives were synthesized via Lumiere-Barbier acetylation, Schotten-Baumann ammonolysis and Buchwald-Hartwig cross-coupling methods respectively. The FTIR, 1 H-NMR, 13 C-NMR and elemental analytical data were employed in the structural characterization. In vitro and in silico antioxidant and antimicrobial studies were carried out. Results: Compounds 1b and 1d displayed the best in vitro antibacterial activities against Escherichia coli, Salmonella typhi, Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and antifungal activities against Candida albican sand Aspergillus niger. Compound 1f
Indian journal of science and technology, Mar 7, 2020
Objective: To synthesize new alanine-based phenyl sulphonamide derivatives with significant antim... more Objective: To synthesize new alanine-based phenyl sulphonamide derivatives with significant antimicrobial and antioxidant activities. Methods: The reaction of alanine with benzenesulphonyl chloride afforded compound 3a. The ammonolysis of its N-acylated derivative gave the carboxamide which yielded the aryl/heteroaryl derivatives compounds 3d, 3e, and 3f via Buchwald-Hartwig nickel catalyzed amidation reaction. Structures agreed with the spectra data. Their antimicrobial activities, antioxidant activities, and molecular docking interactions were evaluated. Findings: Compounds 3f and 3a were the best antimicrobial agents with minimum inhibitory concentration (MIC) range of 0.5-1.0 µg/ml while compound 3a displayed the highest in vitro antioxidant percentage inhibition of 95.70% and the best 50% inhibitory concentration (IC 50) value of 1.072 ± 0.002 µg/ml comparable to ascorbic acid of 96.38% antioxidant percentage inhibition and 0.999 ± 0.001 µg/ml IC 50 value. Compounds 3c, 3a, and 3f had the highest in silico antibacterial, antifungal, and antioxidant binding energies of −10.03, −11.79, and −13.13 kcal/mol, respectively. Novelty/improvement: Alanine was found to potentiate the antimicrobial and antioxidant actions of benzenesulphonamide and carboxamide derivatives.
Indian Journal of Science and Technology, 2020
Objective: To synthesize new alanine-based phenyl sulphonamide derivatives with significant antim... more Objective: To synthesize new alanine-based phenyl sulphonamide derivatives with significant antimicrobial and antioxidant activities. Methods: The reaction of alanine with benzenesulphonyl chloride afforded compound 3a. The ammonolysis of its N-acylated derivative gave the carboxamide which yielded the aryl/heteroaryl derivatives compounds 3d, 3e, and 3f via Buchwald-Hartwig nickel catalyzed amidation reaction. Structures agreed with the spectra data. Their antimicrobial activities, antioxidant activities, and molecular docking interactions were evaluated. Findings: Compounds 3f and 3a were the best antimicrobial agents with minimum inhibitory concentration (MIC) range of 0.5-1.0 µg/ml while compound 3a displayed the highest in vitro antioxidant percentage inhibition of 95.70% and the best 50% inhibitory concentration (IC 50) value of 1.072 ± 0.002 µg/ml comparable to ascorbic acid of 96.38% antioxidant percentage inhibition and 0.999 ± 0.001 µg/ml IC 50 value. Compounds 3c, 3a, and 3f had the highest in silico antibacterial, antifungal, and antioxidant binding energies of −10.03, −11.79, and −13.13 kcal/mol, respectively. Novelty/improvement: Alanine was found to potentiate the antimicrobial and antioxidant actions of benzenesulphonamide and carboxamide derivatives.
The International Journal of Science & Technoledge, 2019
Chemical and Physical Evaluation of Natural Dyes from Hibiscus Sabdariffa Linn (Zobo), Bamphia Ni... more Chemical and Physical Evaluation of Natural Dyes from Hibiscus Sabdariffa Linn (Zobo), Bamphia Nitida (Camwood) and Indigofera Tinctoria (Tropical Indigo Plant) 1. Introduction Natural dyes have been used extensively since long periods. It was practiced during the Bronze Age in Europe. The earliest written record of the user of natural dyes was found in China dated 2600BC (Siva, 2007). The colour of a dyed fabric depends on the nature of the chromophones (the coloured portion of a dye) as well as the substituent functional groups, the auxochromes (certain functional groups which slightly alters the colour) of the dye molecular species (Padma, 2000). Dye may be defined as coloured substances which impact more or less permanent colour to other materials. Such substances with considerable colouring capacity are widely employed in the textile, pharmaceutical, food, cosmetics, plastics, photographic and paper industries (zollinger, H, carneiro, P.A. 1987). Majority of natural dyes need a chemical in the form of metal salts to create an affinity to the fibers and pigment. These chemicals are called mordants. Common mordants used are alum, chrome, copper sulphate, ferrous sulphate etc. (Siva, 2007), Mahangade et al 2009, Samanta and Agarwal, 2009). Hisbiscussabadariuffalinn (Zobo) is a shrub belonging to the family malvaceae. The leaf is reported to contain protein, fat, carbohydrate, fibre, calcium, phosphorus, iron, thiamine, riboflavin, miancin and ascorbic acid (Watt, J.M and Breyer, et al, 1962). The flower yields a purple dye, the major pigment identified is daphriphylline (as above). Bamphianitida (camwood) also known as African sandal wood is a shrubby, hard-wooded African tree. Its wood is commonly used to make a red dye. The source of the indigo dye is the many species of genus indigofera called elu which often times grow wild throughout Nigeria. The name "indigo" derived from Latin word indicum implying from India (Noah
Inorganica Chimica Acta, 2017
In search of a new antimicrobial and antioxidant with improved potency, we designed and synthesiz... more In search of a new antimicrobial and antioxidant with improved potency, we designed and synthesized a pair of chromone hydrazones and their transition metal complexes. The characterization and elucidation of the structure of the prepared compounds were performed by elemental analysis, IR, electronic, EPR and thermo gravimetric analyzes, as well as conductivity and magnetic susceptibility measurements. The EPR spin Hamiltonian parameters of copper complexes were calculated. The spectroscopic data showed that the ligands act as a monobasic tridentate. The coordination sites with the metal (II) ion are pyrone oxygen, azomethine nitrogen and hydrazonic oxygen. Hydrazones and their metal complexes have shown antimicrobial activity against Gram-positive bacteria (S. aureus and B. subtilis); Gram-negative bacteria (P. aeruginosa and E. coli) and fungus (C. albicans) and also the synthesized ligands were tested for their antioxidant activity in vitro by DPPH scanning and the ABTS radical method. The substitution requirements for favorable antioxidant activity were investigated. Compounds containing a phenolic hydroxyl group at the imine (azomethine) position as well as an additional electron donor group exhibited lower IC 50 values and the result shows that all hydrazones have a significant antioxidant activity compared to the standard antioxidants Trolox.
Fuel Processing Technology, 2009
Synthesis of biodiesel from lard was carried out using potassium hydroxide as a catalyst. A 32 fa... more Synthesis of biodiesel from lard was carried out using potassium hydroxide as a catalyst. A 32 factorial design of experiments was used. The effects of agitation speed and catalyst concentration were studied. A regression model was obtained to predict the methyl ester concentration and adequately describe the experimental range studied.According to this study, the most suitable operational conditions were an
CHEMICAL & PHARMACEUTICAL BULLETIN, 1965
Journal of Applied Sciences and Environmental Management, 2010
Physicochemical characteristics and heavy metal levels in water samples from five river systems i... more Physicochemical characteristics and heavy metal levels in water samples from five river systems in central part of Delta State, Nigeria were investigated to access the quality status of the rivers. All the watersheds selected for study were well distributed and possessed similar geology, climate, soil, and vegetation characteristics. Studies on the water samples collected from the rivers showed that the physicochemical characteristics of the river varied significantly. The mean concentration of total solids within the rivers were 35.46mg/l, 31.57mg/l, 18.82mg/l and 45.53mg/l for Ase, Agbarho, Ethiope, Ekakpamre and Afiesere rivers respectively. Similarly, the mean concentration of heavy metal in the river system gave the following ranges zinc 0.93-2.96mg/l, copper 0.01-0.03mg/l, lead 0.003-0.08mg/l, cadmium 0.00-0.004mg/l, chromium 0.001-0.03mg/l, nickel 0.01-0.004mg/l, manganese 0.008-0.04mg/l, iron 0.03-0.08mg/l. A comparison of the heavy metal concentration in the respective samples and recommended international standard such as WHO 1993 showed that the rivers were not significantly contaminated and are therefore suitable for domestic and industrial purpose. From the findings, there is need to protect the quality of the water systems for recreational, industrial and domestic uses. It is hoped that the result of this study would help the Delta State government and other interest groups to maintain existing projects, plan and also to execute properly future development programs in the study area. @ JASEM
International Journal of Molecular Sciences, Jul 30, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Zenodo (CERN European Organization for Nuclear Research), Feb 22, 2023
The anti-corrosive activity of chitosan (CT) on mild steel in HCl solutions was determined using ... more The anti-corrosive activity of chitosan (CT) on mild steel in HCl solutions was determined using gravimetric and electrochemical methods such linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) methods. The gravimetric measurements indicated that the inhibition efficiencies of CT 47.62-64.25%. The LPR results gave the experimental inhibition efficiency of CT to be 67.46-97.85 % while potentiodynamic polarization resistant method was 56.19-89.09%. The EIS measurements indicated 78.45-90.96 % as an inhibition efficiencies of CT. I.
Molecules
Several nitrogen heterocyclic analogues have been applied to clinical practice, and about 75% of ... more Several nitrogen heterocyclic analogues have been applied to clinical practice, and about 75% of drugs approved by the FDA contain at least a heterocyclic moiety. Thus, nitrogen heterocycles are beneficial scaffolds that occupy a central position in the development of new drugs. The fact that certain nitrogen heterocyclic compounds significantly activate the NRF2/ARE signaling pathway and upregulate the expression of NRF2-dependent genes, especially HO-1 and NQO1, underscores the need to study the roles and pharmacological effects of N-based heterocyclic moieties in NRF2 activation. Furthermore, nitrogen heterocycles exhibit significant antioxidant and anti-inflammatory activities. NRF2-activating molecules have been of tremendous research interest in recent times due to their therapeutic roles in neuroinflammation and oxidative stress-mediated diseases. A comprehensive review of the NRF2-inducing activities of N-based heterocycles and their derivatives will broaden their therapeuti...
Book Publisher International (a part of SCIENCEDOMAIN International), Apr 21, 2022
International Journal of Molecular Sciences
The surge of scientific interest in the discovery of Nuclear Factor Erythroid 2 (NFE2)-Related Fa... more The surge of scientific interest in the discovery of Nuclear Factor Erythroid 2 (NFE2)-Related Factor 2 (NRF2)-activating molecules underscores the importance of NRF2 as a therapeutic target especially for oxidative stress. The chemical reactivity and biological activities of several bioactive compounds have been linked to the presence of α,β-unsaturated structural systems. The α,β-unsaturated carbonyl, sulfonyl and sulfinyl functional groups are reportedly the major α,β-unsaturated moieties involved in the activation of the NRF2 signaling pathway. The carbonyl, sulfonyl and sulfinyl groups are generally electron-withdrawing groups, and the presence of the α,β-unsaturated structure qualifies them as suitable electrophiles for Michael addition reaction with nucleophilic thiols of cysteine residues within the proximal negative regulator of NRF2, Kelch-like ECH-associated protein 1 (KEAP1). The physicochemical property such as good lipophilicity of these moieties is also an advantage b...
Chiang Mai Journal of Science
acids and sulfonyl chloride. The characterization of the compounds was done using FTIR, 1H-NMR, 1... more acids and sulfonyl chloride. The characterization of the compounds was done using FTIR, 1H-NMR, 13C-NMR, and elemental analysis. Their antioxidant, antimalarial, antimicrobial activities and molecular docking were evaluated. Compounds 5h (MIC, 0.3, 0.5, 0.3 and 0.4 mg/mL) was the most potent antibacterial agent against Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Salmonella typhi, compounds 5a (MIC, 0.7 mg/mL) and 5g (MIC, 0.7m g/mL) were most potent against Pseudomonas aeruginosa while compound 5e (MIC, 0.5 and 0.8 mg/mL) had the best in vitro antifungal activity against Aspergillus niger and Candida albicans. Compound 5d (1C50 = 1.128 μg/mL) displayed an antioxidant activity comparable with ascorbic acid (1C50 = 1.000 μg/mL) and compound 5e (4, 14, 4%) effected the most signifi cant reduction in the percentage malaria parasitaemia comparable with artemeter lumefantrin (5, 4, 4%) after 5 days of treatment of the mice. From the molecular docking results, compound 5...
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Papers by Melford C Egbujor (Ph.D)