Ductile keratin films from deep eutectic solvent-fractionated feathers.

Feathers, an industrial by-product, are a valuable source of keratin that could be used, for example, in the preparation of films for biomedical and packaging applications. However, the utilisation of feather keratin requires scalable processes to convert feathers into a feasible keratin stream. This paper shows how deep eutectic solvent (DES) fractionated feathers could be converted into strong films.

Comparison of enzymatic and pH shift methods to extract protein from whole Baltic herring (Clupea harengus membras) and roach (Rutilus rutilus).

This study aimed to establish the differences between enzymatically extracted hydrolysates and pH shifted protein isolates from whole Baltic herring and roach in terms of polypeptide patterns, functionality, sensory properties, microbial quality, yield, and composition. Alkaline extraction resulted in the highest yields, whereas the hydrolysates showed the highest protein contents. The hydrolysates showed higher protein solubility (86.

Green process to regenerate keratin from feathers with an aqueous deep eutectic solvent.

Poultry feathers, a source of keratin, are a significant side stream from the food industry, for which valorization is essential considering the circular economy aspects. For this, ecofriendly processes are the tools that allow the easy and feasible transformation of the feathers. Deep eutectic solvents (DESs) are generally considered as inexpensive, relatively simple, mild and environmentally friendly solvents which can dissolve proteins from protein-rich biomasses.

The impact of fermentation with exopolysaccharide producing lactic acid bacteria on rheological, chemical and sensory properties of pureed carrots (Daucus carota L.).

Fermentation with lactic acid bacteria (LAB) offers a natural means to modify technological and nutritional properties of foods and food ingredients. This study explored the impact of fermentation with different exopolysaccharide (EPS) producing LAB on rheological, chemical and sensory properties of puréed carrots in water, as a vegetable model, with the focus on texture formation. The screening of 37 LAB strains for starter selection revealed 16 Lactobacillus, Leuconostoc and Weissella strains capable of EPS (dextran, levan, and/or β-glucan) production in the carrot raw material.

Impact of total solid content and extraction pH on enzyme-aided recovery of protein from defatted rapeseed (Brassica rapa L.) press cake and physicochemical properties of the protein fractions.

Pectinase treatment was used to facilitate protein recovery from defatted rapeseed (Brassica rapa) cold-pressing residue in water-lean conditions and without pH adjustment. Effect of extraction pH on protein yield and physiochemical properties of the protein concentrates was assessed. Enzymatic hydrolysis of carbohydrates was feasible at high (40%) solid content and improved protein recovery at pH 6.

Effect of enzyme-aided cell wall disintegration on protein extractability from intact and dehulled rapeseed (Brassica rapa L. and Brassica napus L.) press cakes.

Cell-wall- and pectin-degrading enzyme preparations were used to enhance extractability of proteins from rapeseed press cake. Rapeseed press cakes from cold pressing of intact Brassica rapa and partially dehulled Brassica napus seeds, containing 36-40% protein and 35% carbohydrates, were treated with pectinolytic (Pectinex Ultra SP-L), xylanolytic (Depol 740L), and cellulolytic (Celluclast 1.5L) enzyme preparations.

Structural changes and allergenic properties of β-lactoglobulin upon exposure to high-intensity ultrasound.

Scope: The aim of this work was to investigate the effects of high-intensity ultrasound (sonication), on the structure and allergenicity of the major cow's milk allergen, beta-lactoglobulin (BLG).

Methods And Results: Structural changes upon sonication of BLG were monitored by circular dichroism spectroscopy, tryptophan emission fluorescence, hydrophobic dye and retinol binding, as well as digestibility and phenol-oxidase cross-linking capacity. Allergenicity was monitored in individual patients' sera, basophil activation test, and skin prick testing in 41 cow's milk allergy patients.

Digestibility and allergenicity assessment of enzymatically crosslinked beta-casein.

Crosslinking enzymes are frequently used in bioprocessing of dairy products. The aim of this study was to examine the effects of enzymatic crosslinking on IgE binding, allergenicity and digestion stability of beta-casein (CN). beta-CN was crosslinked by transglutaminase, tyrosinase, mushroom tyrosinase/caffeic acid and laccase/caffeic acid.

Crosslinking food proteins for improved functionality.

Different possibilities for protein crosslinking are examined in this review, with special emphasis on enzymatic crosslinking and its impact on food structure. Among potential enzymes for protein crosslinking are transglutaminase (TG) and various oxidative enzymes. Crosslinking enzymes can be applied in cereal, dairy, meat, and fish processing to improve the texture of the product.

Oxidation of peptides and proteins by Trichoderma reesei and Agaricus bisporus tyrosinases.

The capability of a novel tyrosinase from Trichoderma reesei (TrTyr) to catalyse the oxidation and oxidative cross-linking of l-tyrosine (l-Y) and tyrosine side-chains in GYG and EGVYVHPV peptides, in bovine serum albumin (BSA) and beta-casein proteins as well as in proteinaceous wool fibres was studied by oxygen consumption measurement, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), reverse phase high-performance liquid chromatography (RP-HPLC), matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and fluorescence microscopy. TrTyr was compared to the well-characterised tyrosinase from Agaricus bisporus (AbTyr) in terms of oxidation and cross-linking. According to the results obtained TrTyr was capable of cross-linking peptides and proteins more efficiently than AbTyr.

Production in Trichoderma reesei of three xylanases from Chaetomium thermophilum: a recombinant thermoxylanase for biobleaching of kraft pulp.

Three endoxylanase genes were cloned from the thermophilic fungus Chaetomium thermophilum CBS 730.95. All genes contained the typical consensus sequence of family 11 glycoside hydrolases.

Tyrosinase-catalyzed grafting of sericin peptides onto chitosan and production of protein-polysaccharide bioconjugates.

The capability of Agaricus bisporus tyrosinase to catalyze the oxidation of tyrosine residues of silk sericin was studied under homogeneous reaction conditions, by using sericin peptides purified from industrial wastewater as the substrate. Tyrosinase was able to oxidize about 57% of sericin-bound tyrosine residues. The reaction rate was higher than with silk fibroin, but lower than with other silk-derived model peptides, i.

Enhanced production of cellobiohydrolases in Trichoderma reesei and evaluation of the new preparations in biofinishing of cotton.

In the search for suitable cellulase combinations for industrial biofinishing of cotton, five different types of Trichoderma reesei strains were constructed for elevated cellobiohydrolase production: CBHI overproducers with and without endoglucanase I (EGI), CBHII overproducers with and without endoglucanase II (EGII) and strains overproducing both CBHI and CBHII without the major endoglucanases I and II. One additional copy of cbh1 gene increased production of CBHI protein 1.3-fold, and two copies 1.