Publications by authors named "Nazlin K Howell"

Hypertension is a threatening chronic disease, which become a global killer among the adult population. The mortality rate increasing day by day even several Angiotensin I-converting enzyme (ACE) inhibitor drugs were introduced. Bioactive peptides derived from aquatic resources exhibits potential ACE inhibitory activity.

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Fish lipids are comprised of considerable quantities of polyunsaturated acids and are prone to oxidation, producing reactive oxygen species and hydroperoxides. This study aimed to evaluate the biochemical and structural alterations in Caco-2 cells following exposure to 100 μg/mL methyl linoleate or fish oil, and then radiated for 24, 48 or 72 h. Electron spin resonance spectroscopy detected free radicals in the lipid membrane, Raman microscopy observed biochemical alterations and atomic force microscopy identified changes in morphology, such as the breakdown of DNA bonds.

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With limited protein resources and depleting commercial fish species there is the need to improve utilization of some of the lesser known species which are underutilized, for example, big eye grunt (burrito), and the flying gurnard (), (other names Cephalocanthus volitans (local) ). This study was to characterize some of the proximate and biochemical properties of burrito and the flying gurnard so as to evaluate their potential for use in human nutrition and other value-added products. Proximate and chemical analysis were determined by the methods of AOAC.

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Egg yolk peptides were successfully prepared from egg yolk protein by-products after lecithin extraction. Defatted egg yolk protein was hydrolyzed with pepsin and pancreatin and purified by gel filtration to produce egg yolk gel filtration fraction (EYGF-33) with antiproliferative activity. The highlight of this study was that the peptide EYGF-33 (1.

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In this study, we investigated the extent of the cytotoxicity effect of oxidised lipids and whether tea catechins namely (-)epigallocatechin-3 gallate (EGCG) decreased lipid peroxidation in caco-2 cells. Cells treated with 0-100 microg/ml fish oil or methyl linoleate (ML) oxidised by UV irradiation for 24 h, 48 h and 72 h, indicated a substantial decrease in cell viability especially in samples treated with 100 microg/ml oxidised lipid. Addition of malondialdehyde (MDA) and hydroxynonenal (50 microM) also reduced cell viability.

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The effect of frozen storage on lipid peroxidation in Atlantic mackerel (Scomber scombrus) stored for up to 26 weeks at -10 or -80°C (control), with and without green tea antioxidants, was investigated. Hydroperoxides (PV) and aldehydes (TBARS) were measured by HPLC and LC-MS and hexanal by GC. There was an increase in peroxide value which was associated with an increase in aldehydes, followed by hexanal increase with storage time and at a higher temperature of -10°C compared with samples stored at -80°C.

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Fourier transform (FT) Raman spectroscopy was used to elucidate heat-induced structural changes of albumin, globulins, serum, and plasma protein solutions (15% w/w) as affected by pH (4.5, 6.0, and 7.

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Oxidised lipids are reported to interact with proteins causing undesirable changes in nutritional and functional properties including a loss of amino acids, cross-linking and damage to proteins and DNA. ESR spectroscopy with spin trapping was used to study the type of radical species generated in methyl linoleate and the transfer of the radical to protein beta-lactoglobulin. Antioxidants vitamins C and E reduced lipid oxidation and subsequent transfer of the radical to the protein as shown by the shape and size of the radical adduct.

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The effect of frozen storage (-10 and -30 degrees C), formaldehyde, and fish oil on collagen, isolated from cod muscle, was investigated. Salt- and acid-soluble collagen fractions as well as insoluble collagen indicated changes in solubility on frozen storage. Differential scanning calorimetry (DSC) showed a highly cooperative transition at 28.

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To investigate the role of antioxidants and cryoprotectants in minimizing protein denaturation in frozen lean fish, cod fillets were treated with either antioxidants (vitamin C (500 mg kg(-1)) or vitamin C (250 mg kg(-1)) + vitamin E (250 mg kg(-1))), antioxidants (vitamins C + E 250 mg kg(-1)each) with citrate (100 mg kg(-1)), cryoprotectants (4% (w/w) sucrose + 4% (w/w) sorbitol), or a mixture of antioxidants (vitamins C + E 250 mg kg(1)), citrate (100 mg kg(-1)), and cryoprotectants (sucrose 40 g kg(-1) + sorbitol 40 g kg(-1)). Untreated and treated fish samples were stored at -10 degrees C; cod fillets stored at -30 degrees C were used as a control. Stored frozen samples were analyzed at intervals for up to 210 days for changes in protein extractability, thermodynamic parameters (transition temperature T(m) and enthalpy DeltaH), structure by FT-Raman spectroscopy, and rheological properties by large and small deformation tests.

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