A chitosan-glucose derivative (ChG) with lower antimicrobial activity against whey native probiotic yeast K. marxianus VM004 was synthesized by the Maillard reaction. The ChG derivative was ...characterized by FT-IR, 1H NMR, and SLS to determine the structure, deacetylation degree (DD), and molecular weight (Mw). In addition, we evaluated the antioxidant, cytotoxic, and antimicrobial activities of ChG. ChG was then used for microencapsulation of K. marxianus VM004 by spray drying. The microcapsules were characterized by evaluating their encapsulation yield, encapsulation efficiency, morphology, tolerance to the gastrointestinal tract, and viability during storage. The results indicated that a non-cytotoxic product with lower MW and DD and higher antioxidant activity than native chitosan was obtained by the Maillard reaction. The yeast ChG microcapsules exhibited an encapsulation efficiency >57 %, improved resistance to gastrointestinal conditions, and enhanced stability during storage. These results demonstrate that ChG may be a promising wall material for the microencapsulation of probiotic yeasts.
•Chitosan-glucose derivative (ChG) did not show antimicrobial activity against yeast.•ChG is not-cytotoxic and shows higher antioxidant activity than native chitosan.•Mw and deacetylation degree of ChG decreases by approximately 10 %.•Microencapsulation in ChG improved resistance to the gastrointestinal conditions.•Crosslinking microcapsules improves tolerance to the intestinal tract and storage stability.
The agro-industry produces numerous byproducts that are currently underused, and its waste contributes to environmental pollution. These byproducts represent an important and economical source of ...bioactive ingredients, which can promote the sustainable development of high-value-added functional foods. In this context, micro- and nanoencapsulation systems allow for the incorporation and stabilization of the bioactive agents in foods. This perspective will review recent advances in the use of agro-industrial byproducts as a source of bioactive agents. In addition, the latest advances in micro- and nanoencapsulation to improve the stability, solubility, and bioaccessibility of bioactive agents as functional food ingredients are exposed.
Abstract
Bacteriocins from Gram-positive bacteria have been proposed as natural food preservative and there is a need for large-scale production for commercial purposes. The aim of the present work ...is to evaluate whey, a cheese industrial by-product, for the production and microencapsulation of enterocin CRL35. Whey proved to be a promising basal medium for bacterial growth although the bacteriocin production was quite low. However, it could be much favored with the addition of yeast extract at concentrations as low as 0.5%. Besides improving bacteriocin production, this peptide was successfully microencapsulated by spray drying using whey protein concentrate and a chitosan derivative as wall materials. Microcapsules averaging 10 ± 5 μm diameter were obtained, with good structural integrity and high antimicrobial activity with a stability of at least 12 weeks at 4°C. In summary, sustainable bacteriocin production and microencapsulation was achieved recycling whey or its derivatives. In addition, the formulation owns high antimicrobial activity with a long shelf life. The development of a food preservative may represent a green solution for handling whey.
The production of enterocin CRL35 in whey and yeast extract followed by microencapsulation represents a green solution for industrial byproducts, obtaining an efficient food preservative with long shelf life.
Summary
The aim of this study was to develop and evaluate the bioactive properties and storage stability of microcapsules (MCs) obtained by co‐encapsulation of the potential probiotic yeast
...Kluyveromyces marxianus
VM004 and peanut skin polyphenolic extract (PSE) by spray drying, using whey protein concentrate (WPC) and water‐soluble chitosan (WSCh) as wall materials. The results showed that the selected wall materials provided protection to yeast during spray drying, storage, and simulated gastrointestinal conditions, obtaining better results for WPC and higher concentrations of PSE. Moreover, all formulations demonstrated cytoprotective effects against menadione‐induced oxidative stress in normal rat ileum epithelial cells (IEC‐18) at all concentrations and storage temperatures evaluated. These results suggest that the obtained MCs could be potential functional food ingredients, considering their antioxidant, cytoprotective, and potential probiotic properties.
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•Water-soluble chitosans were obtained by Maillard reaction with glucose or lactose.•Chit derivatives enable immobilization of glucose oxidase and lactate oxidase.•A highly efficient ...glucose biosensor was obtained by assembling G-Chit and GOx.•The analytical response was tested in milk samples with negligible matrix effects.
In this work we demonstrate for the first time the advantages of using water-soluble chitosan polycation obtained by Maillard reaction with glucose (G-Chit) or lactose residues for the immobilization of glucose oxidase (GOx) and lactate oxidase by the layer-by-layer adsorption method onto carbon paste electrodes. Besides its solubility in enzyme-compatible media, these polymers have a suitable charge density for electrostatic adsorption and allow adequate charge transfer at the electrode-solution interface. Based on the analysis of the effect of the type of chitosan derivative on the enzymatic response; we built an efficient biosensor based on G-Chit and GOx. The multilayered structure made of three bilayers of G-Chit and GOx showed the best performance; the biosensor exhibits a sensitivity of (12.4 ± 0.3) µA mM−1 cm−2 in a glucose concentration range from 180 µM to 1.75 mM. In addition, the analytical response of this biosensor was tested in milk samples with negligible effects of the matrix. The results confirm the suitability of these chitosan derivatives for the adsorption of enzymes and the construction of supramolecular structures. The favorable environment for the enzymatic activity results in bioelectrodes with fast responses for quantification of glucose even in a complex matrix like milk.
The objective was to evaluate the technological processing (protection strategies and storage conditions) influence on viability, on probiotic properties and adsorbent aflatoxin B1 capacity of ...S. boulardii RC009. Also, the yeast biological safety was evaluated. Lyophilisation (DL) and encapsulation + lyophilisation (EL) were conducted. Yeast protected with maltodextrin (M) or WPC stored at 4 °C reduced 1 and 2 log the viability, respectively. Yeast protected with M stored at 25 °C reduced 1 log after 70 d; with WPC the viability significantly reduced 3 log after 30 d. Technological processing improved the coaggregation’s capacity with pathogens and DL process allowed the greatest AFB1 adsorption. S. boulardii 106 cells/mL were no toxic to Vero cells (p˂0.05). Saccharomyces boulardii RC009 protected with M or WPC maintained viability after technological processing. It possesses a great capacity for AFB1 adsorption and probiotic properties and could be considered a candidate with proven safety for functional food products development.
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•Commercial refinery syrup was a good substrate for Saccharomyces boulardii growth.•Maltodextrin and WPC were efficient protectors in ensuring the yeast viability.•The lyophilised yeast achieved high percentages of AFB1 adsorption.•Saccharomyces boulardii cells were non-toxic in Vero cells up to 106 CFU/mL.
Whey is the main byproduct of the cheese industry. While the composition is variable, it retains up to 55% of milk nutrients. The beneficial features of whey indicates a promising source of new ...potentially probiotic strains for the development of food additives destined for animal production. The aim of this study was to identify Kluyveromyces spp. isolated from whey, to study some probiotic properties and to select the best strain to be encapsulated using derivatised chitosan. Kluyveromyces marxianus strains (VM003, VM004 and VM005) were isolated from whey and identified by phenotypic and molecular techniques. These three yeast strains were able to survive under gastrointestinal conditions. Moreover, they exhibited weak auto-aggregation and co-aggregation with pathogenic bacteria (Salmonella sp., Serratia sp., Escherichia coli and Salmonella typhimurium). In general the K. marxianus strains had a strong antimicrobial activity against pathogenic bacteria. The potential probiotic K. marxianus VM004 strain was selected for derivatised-chitosan encapsulation. Material treated with native chitosan exhibited a strong antimicrobial activity of K. marxianus, showing a total growth inhibition at 10 min exposure. However, derivatised-chitosan encapsulation showed a reduced antimicrobial activity. This is the first study to show some probiotic properties of whey-native K. marxianus, in vitro. An encapsulation strategy was applied using derivatised chitosan.
•Water-soluble chitosan-lactose derivatives were synthesized by Maillard reaction.•Derivatives with lower Mw, DD and greater solubility than chitosan were obtained.•Antioxidant activity of ...derivatives was greater than or equal to that of chitosan.•Derivatives were not cytotoxicity against epithelial cells of the rat ileum IEC-18.
In this study, water-soluble chitosan (Ch) derivatives were synthesized by the Maillard reaction between Ch and lactose. The Ch derivatives were characterized by FT-IR, 1H-NMR and SLS to determine their structure, degree of deacetylation (DD), and molecular weight (Mw). The solubility at physiological pH, the in vitro antioxidant activity against hydroxyl radical, anion superoxide radical and ABTS cation radical, and the cytotoxicity against epithelial cells of the rat ileum (IEC-18) were also evaluated. The Maillard reaction, derivatives with lower Mw and DD and greater solubility than Ch were obtained. The biological properties of the derivatives were dependent on the concentration, Mw and DD, with antioxidant activity greater than or equal to that of Ch and non-cytotoxic in a wide range of concentrations. The results indicate that Ch derivatization with lactose produces new water-soluble polysaccharides, with antioxidant activity and non-cytotoxic, which can be used as biomaterials for food and pharmaceutical applications.
The aim of this work was to develop antifungal films from whey protein isolate (WPI) added with low quantities of a water soluble derivative of chitosan (WSCh), which was obtained through a Maillard ...reaction with glucosamine hydrochloride. Glycerol was used as plasticizer and sodium tripolyphosphate was added to neutralize WSCh charges, at a working pH of 6.4, to avoid coacervation due to the opposite charges interaction of both biopolymers. Nevertheless, this WSCh derivative also acted as a crosslinking agent mainly through hydrogen bonding with whey proteins, which generated a decrease in the films' solubility and elongation. Possibly a conformational change of the WPI proteins increased the films' surface hydrophobicity (with contact angles greater than 90°), but there were no increases in their mechanical resistance or in barrier to water vapor. WPI/WSCh films showed excellent fungistatic and barrier effects against the growth of fungus strains associated with food spoilage. Aspergillus niger was 100% inhibited when a suspension containing 1 × 103 spores/mL was inoculated on the films' surface (barrier effect), while Penicillium roqueforti was the strain more resistant to WSCh activity. The obtained results suggest interesting properties of these materials to use them as active edible coatings.
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•WPI edible films were activated with low concentrations of water soluble chitosan (WSCh).•WSCh was prepared by Maillard reaction with glucosamine hydrochloride.•Films presented notable fungistatic effects against strains of food spoilage fungi.•WSCh crosslinked protein films through hydrogen bonds.•Studied formulations seemed to have excellent properties as food active coatings.
Background: A crucial aspect of electrochemical enzymatic biosensor development is the immobilization of the enzymes, as it directly influences the sensitivity of the bioelectrode. Among the ...different methods used to incorporate enzymes on the surface of the transducers, layer-by-layer (LbL) self-assembly based on electrostatic interaction with polyelectrolytes of opposite charge stands out due to its simplicity and reproducibility. Aims: The aim of the work was to develop an electrochemical glucose biosensor by LbL assembly of a new functionalized chitosan polycation and the enzyme glucose oxidase (GOx). Methods: Chitosan was chemically functionalized with glucose by the Maillard reaction. The resulting polycation, named G-Chit, is soluble in the medium compatible with the enzyme. The bioelectrode was obtained by alternating adsorption of G-Chit and GOx onto carbon paste electrodes. By selecting the number of bilayer of G-Chit/GOX, the enzyme concentration, and the pH, the electroanalytical performance of the biosensor was optimized. The electrochemical responses were characterized by cyclic voltammetry and chronoamperometry. Results: Under optimized experimental conditions, the biosensor exhibited a sensitivity of (0.81 ± 0.03) µA mM-1 in a glucose concentration range of (0.18 to 1.75) mM. Discussion: Results indicated that catalytic response increases both with the number of G-Chit/GOx bilayers and the enzyme concentration, obtaining the best responses for 3 bilayers and 2 mg mL-1, respectively, while the optimum working pH value was 7.0. Conclusions: The analytical response of the biosensor was tested in milk samples with negligible matrix effects, suggesting a potential application in other dairy products. Results show that G-Chit appears promising for the immobilization of enzymes.
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