No abstract

A proline-rich peptide product prepared from bovine whey protein that was enriched in several hydrophobic amino acids including proline (whey proline-rich peptide, wPRP) was shown to modulate the folding pathway of human amyloid beta peptide 1-42 (Ab42) into oligomers. Concentrationdependent changes in ThT-binding to Ab42 by wPRP indicated suppression of oligomerisation, that was supported by Transmission Electron Microscopy. Suppression of b-sheet and specifically, antiparallel b-sheet structures by wPRP was demonstrated by ATR-FTIR spectroscopy, where evidence for capacity of wPRP to dissociate pre-existing b-sheet structures in Ab42 was also apparent. Suppression of anti-parallel b-sheets of oligomeric Ab42 was associated with rescue of yeast and SH-SY5Y neuronal cells providing important evidence for the association between anti-parallel b-sheet structure and oligomer toxicity. It was proposed that the interaction of wPRP with Ab42 interfered with the antiparallel folding pathway of oligomeric Ab42 and ultimately produced 'off-pathway' structures of lowered total b-sheet content, with attenuated cellular toxicity. IntroductionIn 2010, cases of dementia including Alzheimer's disease (AD) affected 35.6 million people worldwide with predicted increase of 65.7 million to 115.4 million from 2030 to 2050, according to Alzheimer's Disease International, the worldwide federation of Alzheimer's Associations. The substantial projected social and economic burden of AD world-wide has driven the need for evaluation of the costs of the illness, the cost-effectiveness of interventions and ultimately, the implementation of public policies and services.1 Disease-modifying therapies remain a high priority for development and use in AD care, however the current absence of effective disease-modifying therapies reflects the significant challenge posed by this goal. Furthermore, as preventative measures are likely to be most effective in presymptomatic stages of disease, diet and lifestyle interventions are favoured at this stage. Of relevance to this study is the precedent set by the proline-rich peptide extract prepared from ovine colostrums known as 'Colostrinin' 2 for which anti-fibril and other neuroprotective bioactivities have been extensively reported.Amyloid beta (Ab) is a 40 or 42 amino acid cleavage product of Amyloid Precursor Protein (APP) produced in low levels in the normal ageing brain. It is the major component of senile extracellular plaques in the brain of AD patients and increased levels of Ab42 and its self-aggregation in the brain are key events thought to be responsible for the progressive cognitive decline associated with AD.3 In addition to the heterogeneity and toxic variability of extra-cellular amyloid structures, 4 disease progression has also been attributed to the retention of intracellular Ab42.5 Amyloid fibrils comprise highly ordered, cross-bsheet arrays that elongate into long fibrils and aggregate as tangled plaques. Oligomeric Ab42 represents a low mass, soluble form of Ab42 produced by an ear...

Mild heating coupled with fermentation: a novel approach for increasing sulforaphane yield in broccoli.

No abstract

A large proportion of broccoli biomass is lost during primary production, distribution, processing, and consumption. This biomass is rich in polyphenols and glucosinolates and can be used for the production of bioactive rich ingredients for food and nutraceutical applications. This study evaluated thermosonication (TS) (18 kHz, 0.6 W/g, 40–60 °C, 3–7 min) for the pre-treatment of broccoli florets to enhance enzymatic conversion of glucoraphanin into the bioactive sulforaphane. TS significantly increased sulforaphane yield, despite a decrease in myrosinase activity with increasing treatment intensity. The highest sulforaphane yield of ~2.9 times that of untreated broccoli was observed for broccoli thermosonicated for 7 min at 60 °C, which was 15.8% higher than the corresponding yield for thermal processing without sonication (TP) at the same condition. This was accompanied by increase in the residual level of glucoraphanin (~1.8 and 2.3 time respectively after TP and TS at 60 °C for 7 min compared to control samples) indicating that treatment-induced release of bound glucoraphanin from the cell wall matrix and improved accessibility could be at least partially responsible for the enhanced sulforaphane yield. The result indicates the potential of TS for the conversion of broccoli biomass into high sulforaphane broccoli-based ingredients.

Lactoferrin (Lf), present in colostrum and milk is a member of the transferrin family of iron-binding glyco-proteins, with stronger binding capacity to ferric iron than hemoglobin, myoglobin or transferrin. Unlike hemoglobin and myoglobin, iron-bound Lf is reasonably stable to gastric and duodenal digestive conditions. Unlike ferrous iron, ferric iron is not directly reactive with oxygen supporting the capacity of Lf capture of heme iron to suppress reactive oxygen species (ROS) production. We therefore hypothesized that bovine Lf could capture and thereby terminate the cycle of ROS production by heme iron. The transfer of heme iron from either intact or digested forms of hemoglobin and myoglobin and from intact ferritin was demonstrated by in vitro methods, monitoring Fe-saturation status of Lf by changes in absorptivity at 465 nm. The results are discussed in the context of new proposed opportunities for orally administered Lf to regulate oxidative damage associated with heme iron. In addition to potentially suppressing oxidative heme-iron-mediated tissue damage in the lumen, Lf is expected to also reverse the overload of ferritin-bound iron, that accompanies chronic inflammation and aging. These new proposed uses of Lf are additional to known host defense functions that include anti-microbial, anti-viral properties, immune and cancer cell growth regulation. The findings and interpretations presented require clinical substantiation and may support important additional protective and therapeutic uses for Lf in the future.

The objective of this research was to develop a model faba bean drink with a high concentration of protein (>4% w/w). The protein molecular weights and frequency for both faba and soy were assessed using SDS-PAGE. Results showed similarities in the protein molecular weight of both faba and soy (mainly 11S globulin ~Glycinin and 7S globulin ~β-conglycinin). Thus, faba can be considered as a potential soy replica in plant-based milk beverages. Oil-in-water emulsions (5–8% w/w available protein) were prepared using faba bean protein concentrate (FPC), 1% sunflower oil, and 0.2% sunflower lecithin. These emulsions were used as model beverages and were further investigated for UHT processibility, stability, and physicochemical properties. The physicochemical properties of emulsions at various processing stages viz., coarse emulsification, homogenisation, and UHT, were measured. An increase in the protein concentration and thermal treatment resulted in an increased oil droplet size, coalescence and flocculation, and protein aggregation. Lower protein concentrations viz., 5–6%, showed greater negative ζ-potential, and thereby, high dispersibility through enhanced electrostatic repulsions than those of higher concentrations (7–8%). Furthermore, an increase in protein concentration and UHT treatment resulted in an increased creaming index. In total, 21 different volatile compounds were detected and quantified, representing different chemical classes, namely alcohols, aldehydes, ketones, esters, furan, and acids. These volatiles have major consequences for the overall flavour chemistry of the model beverage product. Overall, this study showed the potential for application of faba bean as a protein source in UHT-treated legume-based beverages and identified areas for further development.

Faba beans are one of the most consumed legumes and an emerging source of edible legume-based protein. Efficacy of faba bean protein concentrate (available protein ~ 63%) during ultra-heat treatment (UHT) processing of homogenised oil-in-water (O/W) emulsion was assessed in the present study by using four different concentrations viz., FPC5 ~ 5%, FPC6 ~ 6%, FPC7 ~ 7%, and FPC8 ~ 8%. Additionally, the physicochemical properties of emulsion at various processing stages viz., coarse, homogenised, and UHT were also measured. Overall, this study showed the potential use of faba bean protein as a replica of soy protein in UHT processed legume-based beverages.