Ogadimma Desmond Okagu

University of Ottawa · School of Nutrition Sciences

This study investigated the impact of ionic strength and lipophilicity of bioactive compounds on their interaction with the alkaline soluble pea glutelin fraction (ASF) using the fluorescence quenching technique. A Stern-Volmer quenching constant, KD, of 8.9 ± 0.10, 5.3 ± 0.06, 4.0 ± 0.01, 1.1 ± 0.00, 0.9 ± 0.02, and 0.1 ± 0.00 (×104 M-1) was obser...

Flavour is an important component that impacts the quality and acceptability of new functional foods. However, most flavour substances are low molecular mass volatile compounds, and direct handling and control during processing and storage are made difficult due to susceptibility to evaporation, and poor stability in the presence of air, light, moi...

Compounds with structural similarities to the neurotransmitter (acetylcholine) are mostly used to inhibit the activity of acetylcholinesterase (AChE) in Alzheimer’s disease (AD) therapy. However, the existing drugs only alleviate symptoms of moderate to mild conditions and come with side effects; hence, the search is still on for potent and safer o...

Food protein interaction with other biopolymers, such as tannic acids, within a food matrix can alter their structure and functionality. In this study, the nature of lentil protein-tannic acid (LPTA) interaction and its effect on in vitro peptic hydrolysis were investigated. In LPTA mixtures containing 1% w/v LP and 0.001% - 0.5% TA, a twenty-fold...

Islet amyloid polypeptide (IAPP) fibrillation has been commonly associated with the exacerbation of type 2 diabetes prognosis. Consequently, inhibition of IAPP fibrillation to minimize β-cell cytotoxicity is an important approach towards β-cell preservation and type 2 diabetes management. In this study, three tetrapeptides, TNGQ, MANT, and YMSV,...

Protein‐energy malnutrition is a global challenge that demands urgent attention, especially with the increasing population growth and unmatched food security plans. One strategy is to expand the list of protein sources, such as neglected and underutilized crops, with high protein content. A good number of plant proteins, in addition to their nutrit...

This study investigated the impact of heating and microwave treatment on the in vitro digestibility (using the INFOGEST method) of buckwheat protein isolates (BPIs) and explored the mechanism. The microwave treatment at level 4 (480 W) for 3 min (ML4T3) increased the BPI digestibility by 67.1% over that of the control, while heating for 20—40 min d...

Anti-adhesive activity of wheat germ-derived peptides, which is considered as one of the promising strategies for preventing Helicobacter pylori infection, was investigated. The underlying mechanism of anti-adhesive action was due to peptides acting as receptor analogues and binding to H. pylori adhesin proteins. However, there is lack of informati...

In this study, the nature of lentil protein-tannic acid (LPTA) interaction and its effect on in vitro pepsin digestion were investigated. LPTA mixtures containing 1% w/v LP and 0.001-0.5% TA were prepared and characterized in terms of particle size, thermal properties, and secondary and tertiary structures. A 20-fold increase in particle size was o...

Curcumin-loaded native and succinylated pea protein nanoparticles, as well as zwitterionic giant unilamellar vesicles were used in this study as model bioactive compound loaded-nanoparticles and biomembranes, respectively, to assess bio-nano interactions. Curcumin-loaded native protein-chitosan and succinylated protein-chitosan complexes, as well a...

Islet amyloid polypeptide (IAPP) fibrillation has been commonly associated with the exacerbation of type 2 diabetes prognosis. Consequently, inhibition of IAPP fibrillation to minimize β-cell cytotoxicity is an important approach towards β-cell preservation and type 2 diabetes management. In this study, we identified three tetrapeptides, TNGQ, MANT...

This study aimed to understand the role of the mucus layer (a biological hydrogel) in the transport mechanisms of peptides. Using established in vitro models, the mucin-binding activity and mucus-permeating property of peptides were determined. Uncharged peptides with relatively high hydrophilicity, including MANT, TNGQ, and PASL, as well as cation...

The impact of structural and physicochemical properties of pea globulin, glutelin and albumin on their interaction with curcumin for their functional role in the gastrointestinal delivery of curcumin was investigated. The binding constant K for curcumin binding with the alkaline-soluble glutelin, salt-soluble globulin and water-soluble albumin frac...

Food-derived peptides have demonstrated various biological activities in vitro. Due to their low biostability, bioaccessibility, and bioavailability, in vitro bioactivities of peptides do not always translate into in vivo pharmacological functions. Moreover, bioactive peptides often possess bitter taste and hygroscopicity. These challenges impede t...

The present work investigated the effects of sonication at different amplitudes and durations on the in vitro digestibility of buckwheat protein isolates (BPIs). The conformation, particle size and microstructures of the BPIs were also studied to explicate the possible mechanisms of the sonication-induced changes. The results showed that sonication...

The present work investigated the effects of sonication at different amplitudes and durations on the in vitro digestibility of buckwheat protein isolates (BPIs). The conformation, particle size and microstructures of the BPIs were also studied to explicate the possible mechanisms of the sonication-induced changes. The results showed that sonication...

The influence of pea protein succinylation on the nature and strength of interaction with curcumin for a potential role in encapsulation and gastrointestinal delivery was investigated. Succinylation neutralized the positive charge on lysine residue and increased the effective negative charge on the protein from -34.4 ± 0.2 to -59.9 ± 0.9 mV with co...

Iron, zinc, and calcium are essential micronutrients that play vital biological roles to maintain human health. Thus, their deficiencies are a public health concern worldwide. Mitigation of these deficiencies involves micronutrient fortification of staple foods, a strategy that can alter the physical and sensory properties of foods. Peptide-mineral...

The potential of using insect proteins to encapsulate and protect hydrophobic nutraceuticals within biopolymer nano-complexes was examined. Insect proteins were used to form nanoparticles that were uncoated or coated with chitosan. Initially, the nature of the curcumin-mealworm protein interaction was investigated. Curcumin mainly interacted with t...

Homoleptic Co(II), Cu(II) and Ni(II) complexes of a hydrazone derived from 3‐acetyl‐2‐hydroxy‐6‐methyl‐4H‐pyran‐4‐one (dehydroacetic acid) and 2‐furoic acid hydrazide, and their heteroleptic analogues with 2,2′‐bipyridine were synthesized. The complexes were characterized by spectroscopic methods (ESI‐MS, IR and NMR), elemental analysis, magnetic s...

Co(II), Ni(II) and Cu(II) complexes of a benzohydrazone derivative, obtained by the reaction of dehydroacetic acid and benzohydrazide, have been synthesized and characterized by conventional spectroscopic techniques, elemental analyses, magnetic susceptibility and conductivity methods, and screened for antibacterial, DNA binding and cleavage proper...

Various kinds of vesicles have been produced from plant, animal and inorganic materials for use as delivery vehicles especially in functional food formulation. However, major drawbacks associated with most of them include issues with sustainability, safety, biocompatibility, biorecognition, stability, bioavailability, bioadhesion, generation of rea...

Food-derived proteins are considered ideal materials for the development of encapsulation and delivery system for bioactive ingredients due to their biophysicochemical properties. The size of the protein-delivery systems in the intestinal media is critical in ensuring effective biophysicochemical characteristics such as biorecognition, biocompatibi...

This study evaluated the performance of an Unmodified Ugwuoba-montmorillonite Clay (UUC) and the Acid Modified Ugwuoba-montmorillonite Clay (AMUC) of Nigerian origin as low-cost materials for attenuation of Methylene Blue (MB). Batch sorption methodology was applied in adsorption and desorption studies. AMUC was found to have higher adsorption of M...

Polymers that efficiently interrelate with biological systems have fascinated a lot of curiosity in biosensor application. In order to determine their suitability and conducting abilities, the nature of ground state, excited states properties and binding affinities of such systems must be known. The vertical singlet-triplet gap, electronic transiti...

The wide use of chemicals in modification of kaolinite in order to improve its adsorption capacity is expensive, requires skilled personnel, noxious to the environment and results in secondary contamination. As a result this study investigated an eco and environmental friendly modification of kaolinte using cassava peel to enhance its adsorption fo...