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Regular intake of fucosylated oligosaccharides has been associated with several benefits for human health, particularly for new-borns. Since these biologically active molecules can be found naturally in human milk, research efforts have been focused on the alternative synthetic routes leading to their production. In particular, utilization of fucosidases to perform stereoselective transglycosylation reactions has been widely investigated. Other reasons that bring these enzymes to the spotlight are their role in viral infections and cancer proliferation. Since their involvement in the pathogenesis of these diseases have been widely described, fucosidases have become a target in newly developed therapies. Finally, activity disorders of biologically important fucosidases can lead to health problems such as fucosidosis. What is common for both mechanisms is the interaction between the enzyme and substrates in and around the active site. Therefore, this review will analyse different substrate structures that have been tested in terms of their interaction with fucosidases active sites, either in synthesis or inhibition reactions. The published results will be compared from this perspective. [ABSTRACT FROM AUTHOR]

In recent years, the synthesis of human milk oligosaccharides, particularly fucooligosaccharides, has been investigated. These oligosaccharides provide protection against gastrointestinal diseases for newborns, among other functionalities. α-L-fucosidase from Thermotoga maritima of GH29 family has been reported to produce fucooligosaccharides by means of a transfucosylation reaction. However, the interaction between acceptor and donor substrates, and the enzyme has been little studied. For that reason, and due to the importance of fucooligosaccharides, the present study proposes a theoretical synthesis route employing α-L-fucosidase from T. maritima, lactose as acceptor substrate and pNP-fucose as fucosyl donor. A molecular docking study was carried out using crystallographic structure of α-L-fucosidase from Protein Data Bank. By simulating the theoretical synthesis with T. maritima fucosidase, it was observed that lactose interacts with the enzyme in regions other than the active site. However, it is approaching the active site when the fucose is in the position to form the enzyme-substrate complex. This finding may explain the transfucosylation yield documented in the literature when the proportion of fucosyl acceptor substrate increases concerning that of the donor substrate. [ABSTRACT FROM AUTHOR]

Agroindustrial by-products derived from fruit processing are an important source of biocompounds that can be used as functional food ingredients. The objective of this work was to evaluate cactus pear and pineapple peel flours as an alternative carbon source during fermentation using bacteria with probiotic potential. The total fibre content of both flours was over 60%, with total soluble carbohydrate content around 20%, indicating a good carbon source for lactic acid bacteria. Kinetic parameters indicate that peel flours are a suitable carbon source because the lactic acid bacteria grow (mean growth rate constant, k, values close to glucose, 1.52 h) and acidify the culture media (maximum acidification rate, Vmax, approximately 1.60 pH × 10−3 min−1). There was no difference in prebiotic potential or prebiotic activity score for both the peel flours. Pediococcus pentosaceus performs better during fermentation. In this respect, cactus pear and pineapple peel flours can be used as functional ingredients due to their fermentable properties. [ABSTRACT FROM AUTHOR]

Abstract: An exopolysaccharide (EPS) producing strain of Streptococcus thermophilus was evaluated for the production of Panela cheese using two total solids milk (TSM) concentrations (12.5 and 17.5g/100mL). This ropy strain increased cheese yield; nevertheless, with 12.5 TSM the increment was higher than with 17.5 TSM. Analysis of cheese composition showed that with 12.5 TSM, the ropy strain increased moisture, but did not change the fat or non fat solids on dry weight basis (dwb), suggesting that the increment of the yield is only due to water retention. In 17.5 TSM cheeses the ropy strain caused an increase in the moisture and fat (dwb), suggesting that besides water retention, fat also contributed to the yield. The difference in yield increment could be explained by cheese composition: higher fat content creates a more hydrophobic environment, which would expel more water than the cheese with lower fat content. Electron microscopy showed EPS attached to the protein matrix of the cheeses. In 17.5 TSM cheeses EPS was observed around the milk fat globules (MFG), confirming that higher TSM causes EPS to bind the MFG besides binding the protein matrix, retaining fat within the cheese. Sensory evaluation demonstrated that ropy cheeses were softer and creamier. [Copyright &y& Elsevier]

Abstract: The activity of Kluyveromyces lactis β-galactosidase increased when it was measured in the presence of either β-lactoglobulin or bovine serum albumin, whereas α-lactalbumin showed no effect on enzyme activity. Heating β-lactoglobulin further increased β-galactosidase activity. Affinity chromatography assays demonstrated that lactase bound specifically to β-lactoglobulin, resulting in enzyme activation. Heating β-lactoglobulin in the presence of lactose resulted in a reaction between the protein and the sugar (lactolation), which diminished the binding capacity of the protein to the enzyme and therefore its activating effect. It was concluded that β-lactoglobulin raises lactase activity through two different mechanisms, one of which depends on the release of sulfhydryl groups by heat treatment from the denatured protein, and the other a result of the ability of the native protein to bind the enzyme. [Copyright &y& Elsevier]

In Mexico, whey is discarded into drains without treatment, which represents an environmental problem. It is known that whey is a mixture of nutrients that increase biochemical demand (BOD) and chemical oxygen demand (COD), exceeding the limits established by national and international standards. Some uses of whey have been proposed to reduce the negative impact it produces on the environment. Some of these uses are the production of high‐value raw materials, separation of macromolecules of industrial interest, and the generation of energy, among others. The integral use of waste under a biorefinery scheme represents a viable alternative for the use of this waste. In this way, the chemical composition of the waste can be used to recover compounds with high added value. The main objective of this review is to propose a dairy whey biorefinery to use components of commercial interest. This biorefinery process involves three stages: the first is the separation of lactoferrin using a polyacrylamide matrix (PAM) impregnated with copper; the second is lactic fermentation using the residue resulting from the separation of lactoferrin, from which lactic acid, hydrolyzed proteins, and probiotics will be obtained. Finally, in the third stage, the residue from the previous stage can be used to generate biogas. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]