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This study investigated the protective effect of β-glucan (BG), konjac glucomannan (KGM) and xanthan gum (XG) on thermo-stability and antioxidant capacities of blueberry anthocyanins (ACN) and their interaction mechanisms. Twenty-six glycosylated and acylated ACN were identified, and malvidin-3-O-galactose was predominant (36.78 %) in ACN extracts. Three polysaccharides retained colour and stability and antioxidant capabilities of ACN under thermal-treatments (XG KGM BG). Rheological properties (shear stress, apparent viscosity) of three polysaccharides were enhanced in presence of ACN. UV-visible spectra, SEM and DLS results indicated that co-aggregation between ACN and specific zones of these polysaccharides was formed. TGA and DSC studies confirmed that introductionof three polysaccharides, especially XG could improve thermostability of ACN. FTIR, and molecular dynamics simulations revealed that thermo-stabilization of polysaccharides-ACN conjugates might be attributedto their intermolecular interactions mainly via hydrogen bindings. The protection by water-soluble polysaccharides foresees novel anthocyanins in food products with increased heat-resistant stability.

The demand for intelligent packaging in food sub-freshness monitoring is increasing. Herein, a pH and NH

The application of blueberry anthocyanins (ANs) was limited due to their low in-process stability and bioavailability. In our study, the stability and antioxidant capacity of ANs before and after adding bovine serum albumin (BSA) were examined by simulating various processing, storage (light, sucrose, and vitamin C (Vc)), and in vitro simulated digestion parameters. For this purpose, pH-differential method, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), peroxyl scavenging capacity assay, and cellular antioxidant assay were conducted. BSA at different concentrations, specifically at 0.15 mg/mL, inhibited the degradation of ANs and the loss of antioxidant capacity. The results suggest that BSA has a positive effect on ANs.

Although hazelnut oil is is nutritious, it is easily oxidized during storage. Thus far, changes in lipids during storage have not been comprehensively analyzed. Here, we used ultra-high liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) to dynamically monitor the lipid composition of hazelnut oil during accelerated storage for 24 d. A total of 10 subclasses of 103 lipids were identified. After 24 d, the content of triacylglycerol, diacylglycerol, phosphatidic acid, phosphatidylethanolamine, phosphatidylethanol, ceramide, and total lipids decreased significantly (P 0.05). A total of 51 significantly different lipids were screened (Variable Importance in Projection 1, P 0.05), and these lipids could be used as biomarkers to distinguish fresh and oxidized hazelnut oil. We also detected seven most important pathways by bioinformatics analysis to explore the mechanism underlying changes. Our results provide useful information for future applications of hazelnut oil and provide new insight into edible oil oxidation.

In this study, we tested the in vitro efficacy of a graphene oxide-chitooligosaccharide (GO-COS) complex developed to protect blueberry anthocyanins (An) from degradation by various physicochemical factors and the digestive process. We prepared a GO-COS complex to adsorb An and protect them from the destructive effects of their ambient environment. The complex protected the An under various temperature, pH, light, oxidant, and reductant conditions. We evaluated An content and composition in a simulated digestive system using the pH differential method and the high performance liquid chromatography-mass spectrometry (HPLC-MS). The GO-COS carrier stabilized An in the intestine and protected their peroxyl radical-scavenging capacity. Additionally, we observed a dose-response relationship between An content and cellular antioxidant activity, and simultaneous improvement of An bioavailability when the An were encapsulated in the complex. The complex inhibited HepG2 cell proliferation at the tested dose range. This study provides valuable information for stability of An-rich products.

Thermal processing (TP) and high hydrostatic pressure (HHP) are two important puree processing methods. In this study, the polyphenol oxidase (PPO) and β-glucosidase activities, chromatic values, peroxide radical scavenging capacities (PSCs), cellular antioxidant activities (CAAs), and anthocyanin profiles were evaluated in blueberry puree following TP and HHP treatments. Nine anthocyanins were identified and cyanidin glycosides were the most abundant compounds in the blueberry puree sample. Petunidin-3-O-arabinoside, malvidin-3-O-galactoside, and malvidin-3-O-glucoside concentrations increased at temperatures of 70–90 °C (TP) and a pressure of 300 MPa (HHP). The highest total anthocyanin concentration (503.5 μg/mL) and PSC (13.45 µg VCE/mL) were observed following the TP (90 °C) treatment. Furthermore, a positive correlation was observed between the anthocyanin content and PSC (R2 = 0.655, P

This research established an optimized method for the extraction and enrichment of flavonoids from R. corchorifolius fruit. Under the optimized extraction conditions, 12 flavonoids (1–12) were isolated, of which six (2–4, 9–10, 12) were obtained from R. corchorifolius for the first time. Compound 4 showed significant α-glucosidase (4.96 μM) and α-amylase (8.04 μM) inhibitory effects. Molecular modeling revealed that compound 4 exhibits strong binding with the active sites of α-glucosidase and α-amylase. Lineweaver-Burk plot analysis and surface plasmon resonance revealed the possible dynamic binding mechanism of the flavonoids with α-glucosidase and α-amylase. The enriched flavonoids and compound 4 showed significant hypoglycemic effects in mice administered a high dose of glucose. In this study, a variety of flavonoids with hypoglycemic activity were found for the first time, revealing the rich chemical composition of R. corchorifolius fruit and highlighting the potential value of R. corchorifolius fruit flavonoids as dietary supplements.

The processing stability and antioxidant capacity of blueberry anthocyanins (ANs) in the presence of whey protein isolate (WPI) were examined. WPI was found to enhance both the stability and antioxidant activity of ANs during processing and simulated in vitro digestion, especially at a concentration of 0.15 mg·mL−1. Fluorescence and ultraviolet-visible absorption spectroscopy showed that ANs were primarily stabilized by hydrophobic forces between WPI and malvidin-3-O-galactoside (M3G), the major anthocyanin monomer. Circular dichroism and Fourier-transform infrared spectroscopy confirmed that the structure of WPI changed and the microenvironments of certain amino acid residues were modulated by non-covalent binding to M3G; furthermore, fewer α-helices and more β-sheets were formed. Molecular docking studies revealed that WPI, especially immunoglobulin (IgG), contributed the most to ANs stability via hydrogen bonds and hydrophobic forces according to molecular docking scores (−141.30 kcal/mol). These results provided an important fundamental basis for improving the stabilities of ANs in milk systems.

This study aimed to examine the interaction mechanism between xylitol (XY) and whey protein isolate (WPI) using multispectral techniques and molecular docking. Additionally, we investigated the effect of XY on WPI functionality using the method of fluorescent probe, high-speed dispersion and differential scanning calorimetry. The fluorescence quenching results such as quenching constants, binding constants and thermodynamic parameters showed strong susceptibility to interacting of WPI and its fractions to XY and the sequence was: α-lactalbumin (α-La) > bovine serum albumin (BSA) > β-lactoglobulin (β-Lg). Docking results revealed that XY was bound to the residues of aromatic cluster II in α-La, the hydrophobic cavity of β-Lg and the subdomain IIA of BSA through hydrogen bonding and van der Waals forces, resulting in conformational changes in secondary structures of proteins, which converted α-helix to β-turn and random coils. Further, XY increased thermal stability and emulsifying properties and reduced surface hydrophobicity and zeta-potential of WPI.