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Polymeric Pickering emulsifiers may bring new insights to emulsion theory and practice due to their soft characters. Herein, a group of soft Pickering emulsifiers, chitosan-casein hydrophobic peptides nanoparticles (CS-CHP NPs) were prepared with a non-covalent anti-solvent procedure. The CS-CHP NPs provided the contact angles of 37.2°-87.4°, stabilizing O/W or W/O emulsions with enhanced thermal stability, endowing the emulsion with pH and CO 2 /N 2 responsiveness. The emulsifying behavior and mechanism presented by CS-CHP NPs were different from that of ordinary hard Pickering emulsifiers, where the appropriate contact angle was 37.2° instead of 87.4° for stabilizing O/W emulsions. Moreover, the nanoparticles possess antioxidant, antibacterial activities and excellent biocompatibility. DPPH and ABTS scavenging activity of the CS-CHP NPs were >220% of that of CS NPs. The last, the emulsion provided high-efficient encapsulation of curcumin, making the soft Pickering emulsifiers a group candidate for drug delivery in food, cosmetics and pharmaceutical industry., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Crosslinking with genipin increases the acidic stability of chitosan-based materials, opening an opportunity to explore new applications. In this work, the viability of using chitosan-genipin solutions on cellulose-based materials coating was studied. Non-calendered paper and cardboard were used as raw materials. Different number of chitosan-genipin coating layers (1, 3, 6, 20, and 30) were applied and their influence on the materials mechanical, physicochemical, and barrier properties was studied. The small thickness and basis weight of non-calendered paper resulted in an inefficient adhesion of chitosan-genipin coating to the cellulose fibers. However, in cardboard, chitosan-genipin created a dense layer onto the cellulosic-fibers surface without impairing their mechanical properties. It conferred a greenish color, whose intensity increased with the layers number. The chitosan-genipin coating decreased the cardboard air and water vapor permeability up to 71 % and 52 %, respectively, and acted as a physical barrier for cardboard compounds leaching, being suitable for covering cellulose-based materials., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The aim of this study was to investigate the effects of ultrasound degradation on the physicochemical, rheological and antioxidant properties of Sargassum pallidum polysaccharides (SpPS). The results indicated that the ultrasound irradiation could significantly decrease the average molecule weight (MW), and particle size (Z avg ) of native SpPS. The degradation pattern of SpPS was closely fitted to the first-order polymer degradation (random chain scission). The primary structure of SpPS before and after ultrasound degradation was not changed, and scanning electron microscopy (SEM) analysis showed that the morphology of SpPS was different from those of the degraded SpPS fractions. Rheological analysis indicated that the degraded SpPS solutions exhibited lower apparent viscosities than native SpPS solution at the same concentration, while the elasticity of the degraded fractions at a certain extent was enhanced. Furthermore, appropriately degraded SpPS fractions exhibited stronger DPPH and ABTS scavenging activity., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

To investigate and compare the preliminary structural characteristics and biological activity in vitro of polysaccharides from Sagittaria sagittifolia L. (SSs) by different extration methods, three polysaccharides (SSW, SSU, and SSP) were obtained with hot water, ultrasound-assisted, and subcritical water extraction. Their structural features were elucidated using High Performance Liquid Chromatography (HPLC), Gas Chromatography (GC), Scanning Electron Microscopy (SEM), Infrared Spectroscopy (IR), Atomic Force Microscopy (AFM), Zeta Potential and Congo red methods. Furthermore, the antioxidant activity and immunostimulatory effects were investigated in vitro. Molecular weight and monosaccharide composition analysis exhibited that SSW (2275.0 kDa), SSU (148.7 kDa), and SSP (1984.0 kDa) were heteropolysaccharide with dramatically different monosaccharide species and mole ratios. In addition, SSP exhibited stronger antioxidant activity in vitro and more potent immunomodulatory activity than SSW and SSU. SSP has greater potential to be explored as biologicalagents for use in complementary medicine or functional foods., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Carboxymethyl cellulose (CMC) based novel functional films containing Chinese chives root extract (CRE) at different concentrations (1, 3 and 5 % in w/w) were successfully fabricated. It was revealed by SEM that higher extract concentration triggered the formation of agglomerates within the film. Tensile strength of the films was decreased from 30.91 to 16.48 MPa. Thickness of films was increased from 43 to 84 μm, while decrease in water solubility from 77.51-52.91 %, swelling degree from 55.74 to 40.37 %, and water vapor permeability from 5.76 to 1.17 10 -10 gm -1 s -1  Pa -1 was observed. DPPH and ABTS radical scavenging ability of CMC-CRE films was increased from 0 to 58 % and 82 %, respectively. CMC-CRE5 film showed the highest biodegradability of 58.14 %. The film prepared by the addition of CRE into CMC also exhibited good antioxidant and antimicrobial activity indicating that it could be developed as a bio-composite food packaging material for the food industry., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

A water-soluble neutral polysaccharide (SDQCP-1) was isolated from fruit bodies of Cordyceps militaris cultivated on hull-less barley. SDQCP-1 was composed of mannose, glucose and galactose in the mole ratio of 13.3:1.0:9.7, with an average molecular weight of 19.3 kDa. Based on results from methylation analysis, GC-MS and NMR, SDQCP-1 was elucidated to be a glucogalactomannan with a backbone composed of (1→2)-α-D-Manp (48.4 %) and (1 → 4)-β-D-Glcp (1.2 %) residues. Its side chains were branched at O-6 position of (1→2)-α-D-Manp mainly by (1 → 2)-β-D-Galf or (1 → 6)-α-D-Manp residues which were terminated mainly with α-D-Galf, α-D-Galp residues. Besides exhibiting a good antioxidant capacity with an ORAC FL value of 24.7 mmol Trolox/g and a TEAC value of 202.4 μmol Trolox/g, SDQCP-1 also could stimulate macrophages to release NO, TNF-α, IL-6, and IL-10, and mainly induced M1 polarization of macrophages. The findings indicated that SDQCP-1, from C. militaris cultivated on hull-less barley, could be used as potential natural antioxidant and immunomodulator in functional foods or medicine., (Copyright © 2020 Elsevier Ltd. All rights reserved.)