Development of chitosan-based edible film incorporated with purified flavonoids from Moringa oleifera: Structural, thermal, antibacterial activity and application.

Purified flavonoids (PF) from Moringa oleifera leaves were incorporated in chitosan (CS) polymer at different concentrations (0.5-4%) to produce a novel edible film. The physical, structure, mechanical, and bio-functional characterizations of the film were evaluated. The incorporation of PF significantly (p < 0.05) improved the thickness, solubility, swelling, and color of CS-films. Incorporating 4% of Moringa oleifera purified flavonoids (MOPF) improved the water vapor permeability from 8.85 to 2.47 g-1 s-1 Pa-1, and increased the film surface heterogeneity observed by SEM. Results also indicated that PF enhanced the mechanical properties and thermal stability of CS-films. The FTIR results indicated alterations in the CS-MOPF composite films' characteristics. Additionally, the incorporation of MOPF increased the antioxidation capacity. Furthermore, 4% of MOPF inhibited the activity of pathogenic bacteria in packed beef burgers. These results suggest that CS-MOPF composite films with enhanced technological and bio-functional properties could be industrially applied to increase the shelf-life of packaged foods.

Positive effects of extracellular polysaccharides from Paecilomyces hepiali on immune-enhancing properties by regulating gut microbiota in cyclophosphamide-induced mice.

Paecilomyces hepiali is a precious health-care edible medicinal fungus with rich polysaccharides and exhibits various biological activities. Polysaccharides from P. hepiali fermentation broth (PHP) exhibits good immunomodulatory activity; however, the mechanism underlying PHP-mediated regulation of immunity and gut microbiota remains unclear. To reveal the mechanisms, PHP of different doses were used to intervene cyclophosphamide (CTX)-induced immunosuppressive model mice. The results revealed that PHP facilitated the secretion of serum cytokines, increased the mRNA and protein expression of TLR4/NF-κB signaling pathway. Furthermore, it improved the physical barrier function of the intestine by upregulating the expression of tight junction proteins. PHP increased the proliferation of beneficial bacteria, including, Actinobacteriota, Alistipes, Candidatus_Saccharimonas and unclassified_Clostridia_vadinBB60_group, and reduced the abundance of Proteobacteria, Deferribacterota, Mucispirillum and Escherichia_Shigella, promoted the production of short-chain fatty acids, which were positively associated with immune traits. Thus, as an immune enhancer, PHP has the potential to regulate the intestinal immune response in immunosuppressed mice through modulating gut microbiota.

Enhanced physical properties, antioxidant and antibacterial activity of bio-composite films composed from carboxymethyl cellulose and polyvinyl alcohol incorporated with broccoli sprout seed extract for butter packaging.

This study investigated the development of biodegradable films made from a combination of carboxymethyl cellulose (CMC), Polyvinyl alcohol (PVA), and purified extract of broccoli sprout seed (BSSE). The films were characterized for their color, physical properties, surface morphology, crystallinity, mechanical properties, and thermal properties. The addition of BSSE up to 1.4 % to the film matrix imparted opaque color and increased opacity up to 3.652. The films also became less moisture-absorbent 8.21 %, soluble 19.16 %, and permeable to water vapor 1.531 (× 10-10 g.m-1 s-1 pa-1). By utilizing 0.7 % from BSSE inside films, the surface of the films became smoother but became rough with higher concentrations 2.1 % of BSSE. Fourier transform infrared (FT-IR) analysis showed that there was physical interaction between the BSSE extract and the PV/CM matrix. The films showed good thermal stability, and the incorporation of BSSE improved their ability to preserve the acidity, TBARS, peroxide value, and total color differences of butter during cold storage.

Polysaccharides from Brassica rapa root: Extraction, purification, structural features, and biological activities. A review.

Brassica rapa (B. rapa) roots are attracting increased attention from nutritionists and health-conscious customers because of their remarkable performance in supplying necessary nutrients. Polysaccharides are major biologically active substances in B. rapa roots, which come in a variety of monosaccharides with different molar ratios and glycosidic bond types. Depending on the source, extraction, separation, and purification methods of B. rapa roots polysaccharides (BRP); different structural features, and pharmacological activities are elucidated. Polysaccharides from B. rapa roots possess a range of nutritional, biological, and health-enhancing characteristics, including anti-hypoxic, antifatigue, immunomodulatory, hypoglycemic, anti-tumor, and antioxidant activities. This paper reviewed extraction and purification methods, structural features, and biological activities as well as correlations between the structural and functional characteristics of polysaccharides from the B. rapa roots. Ultimately, this work will serve as useful reference for understanding the connections between polysaccharide structure and biological activity and developing novel BRP-based functional foods.

Composition, Structure, and Techno-Functional Characteristics of the Flour, Protein Concentrate, and Protein Isolate from Purslane (Portulaca oleracea L.) Seeds.

One potential avenue to increase the production of valuable protein ingredients for the food industry is developing vegetable proteins from non-traditional plant sources. In the present study, the composition, structure and techno-functional characteristics of defatted purslane flour (DF), protein concentrate (PC), and protein isolate (AP) were investigated. The results revealed that DF, PC, and PI contained low levels of moisture, ash, and fat. However, there were significant differences (P < 0.05) in protein content between DF, PC, and PI (32.9, 60.8 and 90.9%, respectively). The techno-functional characteristics of purslane proteins were enhanced by processing purslane flour into PC and PI products. Furthermore, the ratios of total essential amino acids to total amino acids in purslane protein samples were well above that stated for ideal food proteins. SDS-PAGE analysis indicated three subunits of protein in DF, PC, and PI. Scanning electron microscopy revealed that DF exhibited a compact-like structure; PC had a small, flaky, but porous type of particle, and PI had an intact flake-like structure. The FTIR analysis revealed that some alterations in the secondary structure of protein were occurred. In summary, purslane proteins can be considered new functional food ingredients with different nutritional and technological characteristics.

Immobilization of ß-Glucosidase from Thermatoga maritima on Chitin-functionalized Magnetic Nanoparticle via a Novel Thermostable Chitin-binding Domain.

Enzyme immobilization is a powerful tool not only as a protective agent against harsh reaction conditions but also for the enhancement of enzyme activity, stability, reusability, and for the improvement of enzyme properties as well. Herein, immobilization of ß-glucosidase from Thermotoga maritima (Tm-ß-Glu) on magnetic nanoparticles (MNPs) functionalized with chitin (Ch) was investigated. This technology showed a novel thermostable chitin-binding domain (Tt-ChBD), which is more desirable in a wide range of large-scale applications. This exclusive approach was fabricated to improve the Galacto-oligosaccharide (GOS) production from a cheap and abundant by-product such as lactose through a novel green synthesis route. Additionally, SDS-PAGE, enzyme activity kinetics, transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR) revealed that among the immobilization strategies for Thermotoga maritime-ß-Glucosidase thermostable chitin-binding domain (Tm-ß-Glu-Tt-ChBD) on the attractive substrate; Ch-MNPs had the highest enzyme binding capacity and GOS production ratio when compared to the native enzyme. More interestingly, a magnetic separation technique was successfully employed in recycling the immobilized Tm-ß-Glu for repetitive batch-wise GOS without significant loss or reduction of enzyme activity. This immobilization system displayed an operative stability status under various parameters, for instance, temperature, pH, thermal conditions, storage stabilities, and enzyme kinetics when compared with the native enzyme. Conclusively, the GOS yield and residual activity of the immobilized enzyme after the 10th cycles were 31.23% and 66%, respectively. Whereas the GOS yield from native enzyme synthesis was just 25% after 12 h in the first batch. This study recommends applying Tt-ChBD in the immobilization process of Tm-ß-Glu on Ch-MNPs to produce a low-cost GOS as a new eco-friendly process besides increasing the biostability and efficiency of the immobilized enzyme.