Browsing by Author "Havea P"

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    Characterization of heat-induced aggregates of beta-lactoglobulin, alpha-lactalbumin and bovine serum albumin in a whey protein concentrate environment
    (Cambridge University Press, 2001) Havea P; Singh H; Creamer LK
    Bovine b-lactoglobulin (b-lg), a-lactalbumin (a-la) and bovine serum albumin (BSA), dispersed in ultra®ltration permeate, that had been prepared from whey protein concentrate solution (100 g}kg, pH 6±8), were heated at 75 °C. The consequent protein aggregation was studied by one-dimensional (1D) and twodimensional (2D) polyacrylamide gel electrophoresis (PAGE). When 100 g b-lg}kg permeate solution was heated at 75 °C, cooled and examined, large aggregates were observed. These aggregates were partially dissociated in SDS solution to give monomers, disulphide-bonded dimers, trimers and larger aggregates. When mixtures of b-lg and a-la or BSA were heated, homopolymers of each protein as well as heteropolymers of these proteins were observed. These polymer species were also observed in a heated mixture of the three proteins. Two-dimensional PAGE of mixtures demonstrated that these polymers species contained disulphide-bonded dimers of b-lg, a-la and BSA, and 1:1 disulphide-bonded adducts of a-la and b-lg, or BSA. These results are consistent with a mechanism in which the free thiols of heattreated b-lg or BSA catalyse the formation of a range of monomers, dimers and higher polymers of a-la. It is likely that when whey protein concentrate is heated under the present conditions, BSA forms disulphide-bonded strands ahead of b-lg and that a-la aggregation with b-lg and with itself is catalysed by the heat-induced unfolded BSA and b-lg.
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    Exploring the Nutrition-Related Health of the Ageing Population in Fiji: A Narrative Review.
    (SAGE Publications, 2024-10-18) Naliva S; Kruger M; Havea P; Wham C
    Fijis' older population aged 55 years and over makes up 14% of the total population and is expected to reach 20% by 2050. This narrative review aimed to examine the health and nutrition status of the aging population of Fiji and sociodemographic determinants. A search strategy was conducted throughout databases, and gray literature from relevant websites was searched. Due to the limited evidence regarding the nutrition, health, and socio-economic factors that impact the aging population in Fiji the inclusion criteria were broad and included both genders (male and female), all publications up until December 2022, all study designs, and gray literature (government/institutional reports, conference proceedings, guidelines, Act, and Policies) . There was no filter for date applied in the search criteria. Studies that did not meet the search criteria were excluded. 20 documents including published articles were included for analysis and result synthesis. Life expectancy at birth for the Fiji population is 68 years. A significant annual increase in mortality rate from endocrine, nutritional, and metabolic diseases has been observed in women aged 75+ but not older men. Women of low-income status are more at risk than men. However, as most investigations aggregate those ≥18 years, there is a lack of information on older adults (≥65 years) health and nutrition status. To improve the health status of older adults, an understanding of the nutritional status of older adults is warranted, especially concerning lifestyle and sociodemographic determinants.