ARTICLE | doi:10.20944/preprints201812.0202.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: pasta; salmon powder; glycaemic index; protein digestibility; polyphenols; antioxidant activity; bioaccessibility
Online: 17 December 2018 (15:59:54 CET)
This research focussed on utilisation of salmon protein and lipid to manipulate pasta glycaemic index and protein digestibility. Salmon fish (Oncorhynchus tschawytscha) powder (SFP) supplemented pasta flour at the from 5% to 20% (w/w). Inclusion of SFP lead to a significant reduction in starch digestibility and hence the potential glycaemic values of pasta (experimental pasta being up to 143% lower than control values). SFP addition to pasta increased the release of phenolic compounds from pasta during both a gastric digestion (179%) and pancreatic digestion ( 133%) in comparison to the control sample. At the same time, the antioxidant activity of the digested pasta was increased by up to 263% (gastric) and 190% (pancreatic) in comparison to durum wheat pasta alone. Interestingly, although protein levels increased with incorporation of SFP, the digestibility values of the protein decreased from 86.41% for the control pasta to 81.95% for 20% SFP pasta. This may indicate that there are interactions between phenolic and protein in the pasta samples which affect overall protein digestibility levels.
ARTICLE | doi:10.20944/preprints201809.0319.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Oxidative stress; blackcurrant; biofunctional cookie; simulated digestion; bioactive metabolites; inflammatory cytokines
Online: 17 September 2018 (15:05:44 CEST)
The improved understanding of the underlying mechanisms of oxidative damage and/or chronic diseases is of high priority in dietary research. Although the chemical extraction of biofunctional molecules from different fruits and cereals have been studied extensively, the impact of food processing and digestion on bioactivity has not been studied systematically. The aim of this study was to investigate the biofunctional potential of blackcurrant powder incorporated into wholemeal wheat and barley cookies in after simulated in vitro digestion. The incorporation of blackcurrant significantly (p<0.05) increased the total phenolic content (about 60 %), significantly improved oxygen radical absorbance capacity (about 25 %) of the cookie digesta. Additionally cellular antioxidant and anti-proliferative activity (lowest EC₅₀ value 1.02 mg/mL) on human liver cancer cell model, HepG2 was significantly enhanced. Bioactive metabolites of blackcurrant incorporated cookies were significantly supressed the inflammatory cytokine genes IL-1β (about 3-fold), IL-6 (about 0.5-fold) and NF-kB (about 2-fold) regulation and upregulated satiety gene NUCB-2/Nesfatin-1 (about 5-fold) compare with wholemeal wheat and barley control cookies. The exerted synergistic effects of this study suggest that there may be a new and effective option to prevent and control chronic diseases in human.
ARTICLE | doi:10.20944/preprints201703.0017.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: green synthesis; silver nanoparticles; trimethylchitosan nitrate; catalytic activity; antibacterial activity; multidrug-resistant Acinetobacter baumannii
Online: 2 March 2017 (08:49:35 CET)
We report a facile route for the green synthesis of trimethylchitosan nitrate-capped silver nanoparticles (TMCN-AgNPs) with positive surface charge. In this synthesis, silver nitrate, glucose, and trimethyl chitosan nitrate (TMCN) were used as silver precursor, reducing agent, and stabilizer, respectively. The reaction was carried out in a stirred basic aqueous medium at room temperature without the use of energy-consuming or expensive equipment. We investigated the effects of the concentrations of NaOH, glucose, and TMCN on the particle size, zeta potential, and formation yield. The AgNPs were characterized by UV-visible spectroscopy, photon correlation spectroscopy, laser Doppler anemometry, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The catalytic activity of the TMCN-AgNPs was studied by the reduction of 4-nitrophenol using NaBH4 as a reducing agent. We evaluated the antibacterial effects of the TMCN-AgNPs on Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus using the broth microdilution method. The results showed that both gram-positive and gram-negative bacteria were killed by the TMCN-AgNPs at very low concentration (< 6.13 μg/mL). Moreover, the TMCN-AgNPs also showed high antibacterial activity against clinically isolated multidrug-resistant A. baumannii strains, and the minimum inhibitory concentration (MIC) was ≤ 12.25 μg/mL.