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Different methods of isolating arabinoxylans (AXs) from triticale were performed to investigate the extraction methods' effects on the physiological functions of the AXs. Structural, antioxidant, and hypoglycemic activities were determined. The molecular weights (MWs) of enzyme- or water-extracted AXs were lower than those of alkali-extracted AXs. Opposite trends were shown by the arabinose–xylose ratio. Enzyme-extracted AXs exhibited higher glucose adsorption capacity and hydroxyl radical-scavenging efficiency than alkali-extracted AXs. The α-amylase inhibition ability, DPPH radical-scavenging capacity, and metal-chelating activity of alkali-extracted AXs were higher than those of enzyme-extracted AXs. Water-extracted AXs had the highest glucose dialysis retardation index. In conclusion, extraction methods can influence the physiological function of AXs through their structural features. AXs with higher MWs and esterified ferulic acid (FA) levels had higher antioxidant ability, whereas AXs with higher solubility and free FA level exhibited higher hypoglycemic activity. [ABSTRACT FROM AUTHOR]

Citrus pectin (CP) and two pectins with distinct molecular weights (CP-1 and CP-2) were prepared using ultrasound-assisted H 2 O 2 /ascorbic acid reaction, and their structural, anticancer, and immunostimulatory properties were investigated. Based on the methylation and nuclear magnetic resonance analyses, the structure of CP-2 was determined to be composed of an α-1,4-linked homogalacturonan backbone that exhibited high levels of O-6 methylation. In addition, both CP-1 and CP-2 induced apoptosis in various cancer cell lines, while CP exhibited minimal impact. All tested CPs activated RAW264.7 cells, promoting the production of nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 by upregulating the expression of TNF-α, IL-6, and inducible NO synthase genes. Among them, CP-2 exhibited the highest immunostimulatory activity closely linked with its molecular weight. Furthermore, we found that CP-2 could activate RAW264.7 macrophages through NOD-like receptor (NLR) signaling pathways involving nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. In summary, the results of this investigation will enhance the comprehension of the structure-function correlation of CP, furthering its application within the functional food industry. • Citrus pectin (CP) and two molecular-weight pectins (CP-1 and CP-2) were prepared. • The structural and biological properties of the CPs were systematically examined. • The immunoregulatory mechanism of CP-2 was elucidated via proteomics analysis. • The findings contribute to revealing the structure-activity relationship of CPs. [ABSTRACT FROM AUTHOR]

Arabinoxylan (AX) has many beneficial health effects that are closely related to its structural characteristics. The current study aimed to investigate the effects of molecular weight (Mw) and degree of substitution (DS) on the antioxidant and hypoglycemic activities of triticale bran AX and its hydrolysates in vitro. At low and similar Mw, the antioxidant activity of AX was inversely proportional to its DS. When DS was close, the antioxidant activity of AX was inversely proportional to its Mw at high DS, but the opposite result was found at low DS. As for the hypoglycemic performance, when DS was similar, the hypoglycemic activity of AX was proportional to its Mw. At low and similar Mw, the α-glucosidase inhibitory ability and glucose adsorption ability of AX was positively correlated with DS, whereas the α-amylase inhibitory ability and glucose delayed absorption ability showed the opposite results. Mw and DS had significant effects on the antioxidant and hypoglycemic activities of AX, and these two factors often need to be combined to explain the varied effects under different conditions. • Bioactivities of AX were closely correlated to their Mw and DS. • At low and similar Mw, the antioxidant activity of AX was inversely proportional to its DS. • At similar DS, the antioxidant activity of AX was inversely proportional to its Mw at high DS, but opposite at low DS. • At similar DS, the hypoglycemic activity of AX was directly proportional to its Mw. [ABSTRACT FROM AUTHOR]

Recently, chitosan film has been widely used to extend the shelf life of food. In this study, high, medium and low molecular weight of chitosan were used as raw materials to prepare a series of films (C1–C27) by controlling the content of chitosan and glycerol, and their mechanical properties, water vapor permeability (WVP), oxygen transmittance (OP), morphology and antibacterial properties were characterized as well. The results indicated that all films had film-forming properties. Among them, the film C16 with high molecular weight, high chitosan content and 50% glycerol/chitosan (w/w) exhibited the excellent transparency (91.2%), elongation at break (28.948%), tensile strength (77.963 MPa), WVP (1.46 × 10−12gcm/cm2·sPa), smooth morphology, denser structure and antibacterial property (Staphylococcus aureus and Escherichia coli). Meanwhile, the preservation properties of chitosan films were evaluated by strawberry preservation. Almost all the studied films had better preservation effect than the commercially available PE films, especially of which the film C16 was the best compared with others. It maintained the physical and chemical parameters (weight loss ratio, total soluble solids, titratable acidity, total ascorbic acid and color change) of strawberry most obviously. Hence, chitosan films had great potential for the industrial application of fruit preservation. [ABSTRACT FROM AUTHOR]

The formation and characterization of conjugates of soybean protein isolate (SPI) and dextran with varying molecular weights (4, 10, and 70 kDa) and their effects on quality of glucono-δ-lactone (GDL)-induced tofu were investigated. The extent of glycosylation was negatively related to the molecular weight of dextran. Thus, the SPI-dextran4 conjugate exhibited a darker color and a biggest decrease in whiteness from 70.49 to 45.51. SPI-dextran70 conjugate exhibited an increased surface hydrophobicity and free sulfhydryl content. Volume-average diameter of SPI-dextran70 conjugate-added soymilk and gel strength of the corresponding tofu ranged from 10.34 to 11.24 μm and 0.068 to 0.083 N, respectively, which were lesser than those of the control (11.12 μm and 0.133 N). However, SPI-dextran10 conjugate incubated for 6 days and SPI-dextran4 conjugate incubated for 2 days increased the gel strength of tofu to 0.146 and 0.143 N, respectively. Conjugates-added tofu exhibited an increased water holding capacity and a discontinuous and loose microstructure, but a lowered whiteness and a color change to yellow. Results demonstrated that the selection of dextran with an appropriate molecular weight and controlling the glycosylation degree were capable of improving the quality of SPI-dextran conjugate-added GDL-induced tofu. • Soybean protein isolate (SPI)-dextran (4, 10, 70 kDa) conjugates were prepared. • Molecular weight of dextran affected the physicochemical properties of conjugates. • SPI-dextran70 conjugates reduced particle size of soymilk and gel strength of tofu. • Impact of SPI-dextran4/10 conjugates on gel strength of tofu depended on reaction time. • The addition of conjugates enhanced the water holding capacity of tofu. [ABSTRACT FROM AUTHOR]