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1.
Int J Biol Macromol ; 271(Pt 1): 132615, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38795900

ABSTRACT

A series of intricate and dynamic physiological healing processes are involved in the healing of skin wounds. Herein, a multifunctional hydrogel is firstly designed and constructed by L-arginine-grafted O-carboxymethyl chitosan (CMCA), catechol-modified oxidized hyaluronic acid (DOHA), and dopamine nanoparticles (pDA-NPs). pDA-NPs were loaded in hydrogel for inherently powerful antimicrobial properties and could be as a cross-linking agent to construct hydrogels. Raffinose (Raf) was further incorporated to obtain CMCA-DOHA-pDA2@Raf hydrogel for its function of modulating epidermal differentiation. The hydrogel has good physicochemical properties and could promote cell proliferation and migration, which shows superior hemostatic capabilities in animal models of hemorrhage. The hydrogel significantly promoted wound healing on rat skin defect models by upregulating VEGF and CD31 and decreasing IL-6 and TNF-α, stimulating neovascularization and collagen deposition in epithelial structures. This multifunctional hydrogel implies the potential to be a dynamic wound dressing.


Subject(s)
Chitosan , Dopamine , Hydrogels , Nanoparticles , Raffinose , Wound Healing , Wound Healing/drug effects , Animals , Hydrogels/chemistry , Hydrogels/pharmacology , Nanoparticles/chemistry , Dopamine/chemistry , Dopamine/pharmacology , Rats , Chitosan/chemistry , Chitosan/analogs & derivatives , Chitosan/pharmacology , Raffinose/chemistry , Raffinose/pharmacology , Cell Proliferation/drug effects , Hyaluronic Acid/chemistry , Hyaluronic Acid/pharmacology , Humans , Male , Cross-Linking Reagents/chemistry , Rats, Sprague-Dawley , Skin/drug effects , Cell Movement/drug effects
2.
Carbohydr Res ; 534: 108948, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37783055

ABSTRACT

Six oligosaccharides were discovered and isolated for the first time from Ziziphi Spinosae Semen. On the basis of spectroscopic analysis, their structures were determined to be verbascose (1), verbascotetraose (2), stachyose (3), manninotriose (4), raffinose (5), and melibiose (6). The prebiotic effect of the oligosaccharide fraction was assayed by eight gut bacterial growth in vitro, revealing a significant increase in cell density, up to 4-fold, for Lactobacillus acidophilus, Lactobacillus gasseri, and Lactobacillus johnsonii. The impact of six oligosaccharides with different degrees of polymerization (DPs) and structures on the growth of Lactobacillus acidophilus was evaluated. As a result, stachyose and raffinose demonstrated superior support for bacterial growth compared to the other oligosaccharides. This study explored the structure-activity relationship of raffinose family oligosaccharides (RFOs) and showed that the more the monosaccharide type, the more supportive the gut bacteria growth when oligosaccharides have the same molecular weight.


Subject(s)
Prebiotics , Semen , Raffinose/chemistry , Raffinose/metabolism , Semen/metabolism , Oligosaccharides/pharmacology , Oligosaccharides/metabolism , Melibiose
3.
Int J Biol Macromol ; 242(Pt 2): 124808, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37211074

ABSTRACT

Raffinose family oligosaccharides (RFOs) in food are the main factors causing flatulence in Irritable Bowel Syndrome (IBS) patients and the development of effective approaches for reducing food-derived RFOs is of paramount importance. In this study, polyvinyl alcohol (PVA)-chitosan (CS)-glycidyl methacrylate (GMA) immobilized α-galactosidase was prepared by the directional freezing-assisted salting-out technique, aimed to hydrolyze RFOs. SEM, FTIR, XPS, fluorescence and UV characterization results demonstrated that α-galactosidase was successfully cross-linked in the PVA-CS-GMA hydrogels, forming a distinct porous stable network through the covalent bond between the enzyme and the carrier. Mechanical performance and swelling capacity analysis illustrated that α-gal @ PVA-CS-GMA not only had suitable strength and toughness for longer durability, but also exhibited high water content and swelling capacity for better retention of catalytic activity. The enzymatic properties of α-gal @ PVA-CS-GMA showed an improved Km value, pH and temperature tolerance range, anti-enzymatic inhibitor (melibiose) activity compared to the free α-galactosidase and its reusability was at least 12 times with prolonged storage stability. Finally, it was successfully applied in the hydrolysis of RFOs in soybeans. These findings provide a new strategy for the development of α-galactosidase immobilization system to biological transform the RFOs components in the food for diet intervention of IBS.


Subject(s)
Chitosan , Irritable Bowel Syndrome , Humans , Raffinose/chemistry , Hydrolysis , alpha-Galactosidase/chemistry , Polyvinyl Alcohol/chemistry , Freezing , Oligosaccharides/chemistry , Hydrogels
4.
Acta Crystallogr D Struct Biol ; 79(Pt 2): 154-167, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36762861

ABSTRACT

The alkaline α-galactosidase AtAkαGal3 from Arabidopsis thaliana catalyzes the hydrolysis of α-D-galactose from galacto-oligosaccharides under alkaline conditions. A phylogenetic analysis based on sequence alignment classifies AtAkαGal3 as more closely related to the raffinose family of oligosaccharide (RFO) synthases than to the acidic α-galactosidases. Here, thin-layer chromatography is used to demonstrate that AtAkαGal3 exhibits a dual function and is capable of synthesizing stachyose using raffinose, instead of galactinol, as the galactose donor. Crystal structures of complexes of AtAkαGal3 and its D383A mutant with various substrates and products, including galactose, galactinol, raffinose, stachyose and sucrose, are reported as the first representative structures of an alkaline α-galactosidase. The structure of AtAkαGal3 comprises three domains: an N-terminal domain with 13 antiparallel ß-strands, a catalytic domain with an (α/ß)8-barrel fold and a C-terminal domain composed of ß-sheets that form two Greek-key motifs. The WW box of the N-terminal domain, which comprises the conserved residues FRSK75XW77W78 in the RFO synthases, contributes Trp77 and Trp78 to the +1 subsite to contribute to the substrate-binding ability together with the (α/ß)8 barrel of the catalytic domain. The C-terminal domain is presumably involved in structural stability. Structures of the D383A mutant in complex with various substrates and products, especially the natural substrate/product stachyose, reveal four complete subsites (-1 to +3) at the catalytic site. A functional loop (residues 329-352) that exists in the alkaline α-galactosidase AtAkαGal3 and possibly in RFO synthases, but not in acidic α-galactosidases, stabilizes the stachyose at the +2 and +3 subsites and extends the catalytic pocket for the transferase mechanism. Considering the similarities in amino-acid sequence, catalytic domain and activity between alkaline α-galactosidases and RFO synthases, the structure of AtAkαGal3 might also serve a model for the study of RFO synthases, structures of which are lacking.


Subject(s)
Arabidopsis , alpha-Galactosidase , alpha-Galactosidase/genetics , alpha-Galactosidase/chemistry , Raffinose/chemistry , Hydrolases , Phylogeny , Galactose
5.
Cells ; 10(6)2021 06 08.
Article in English | MEDLINE | ID: mdl-34201225

ABSTRACT

In human sperm cryopreservation, test yolk buffer and human serum albumin have been used as permeating macromolecular-weight cryoprotectants. In clinical reproductive medicine, human serum albumin is frequently used because of low risks of zoonoses and allergic reactions. However, the risk of allogeneic infectious diseases exists, and the supply may be unstable because human serum albumin is derived from human blood. Therefore, the development of xeno-free human sperm cryopreservative reagents that could overcome the aforementioned problems is warranted. We succeeded in developing a new xeno-free and defined sperm cryopreservation reagent containing glycerol, carboxylated poly-l-lysine, and raffinose. The cryopreservation reagent was not significantly different in terms of sperm motility, viability, and DNA fragmentation and was comparable in performance to a commercial cryopreservation reagent containing human serum albumin. Moreover, the addition of saccharides was essential for its long-term storage. These results may help elucidate the unknown function of macromolecular-weight permeating cryoprotective agents.


Subject(s)
Cryopreservation/methods , Cryoprotective Agents/chemistry , Specimen Handling/methods , Spermatozoa/cytology , Glycerol/chemistry , Humans , Male , Polylysine/chemistry , Raffinose/chemistry
6.
Int J Mol Sci ; 22(5)2021 Mar 02.
Article in English | MEDLINE | ID: mdl-33801421

ABSTRACT

Saccharides protect biostructures against adverse environmental conditions mainly by preventing large scale motions leading to unfolding. The efficiency of this molecular mechanism, which is higher in trehalose with respect to other sugars, strongly depends on hydration and sugar/protein ratio. Here we report an Infrared Spectroscopy study on dry amorphous matrices of the disaccharides trehalose, maltose, sucrose and lactose, and the trisaccharide raffinose. Samples with and without embedded protein (Myoglobin) are investigated at different sugar/protein ratios, and compared. To inspect matrix properties we analyse the Water Association Band (WAB), and carefully decompose it into sub-bands, since their relative population has been shown to effectively probe water structure and dynamics in different matrices. In this work the analysis is extended to investigate the structure of protein-sugar-water samples, for the first time. Results show that several classes of water molecules can be identified in the protein and sugar environment and that their relative population is dependent on the type of sugar and, most important, on the sugar/protein ratio. This gives relevant information on how the molecular interplay between residual waters, sugar and protein molecules affect the biopreserving properties of saccharides matrices.


Subject(s)
Lactose/chemistry , Myoglobin/chemistry , Raffinose/chemistry , Sucrose/chemistry , Trehalose/chemistry , Water/chemistry , Animals , Horses
7.
Int J Mol Sci ; 21(15)2020 Jul 29.
Article in English | MEDLINE | ID: mdl-32751348

ABSTRACT

The synthesis of complex oligosaccharides is desired for their potential as prebiotics, and their role in the pharmaceutical and food industry. Levansucrase (LS, EC 2.4.1.10), a fructosyl-transferase, can catalyze the synthesis of these compounds. LS acquires a fructosyl residue from a donor molecule and performs a non-Lenoir transfer to an acceptor molecule, via ß-(2→6)-glycosidic linkages. Genome mining was used to uncover new LS enzymes with increased transfructosylating activity and wider acceptor promiscuity, with an initial screening revealing five LS enzymes. The product profiles and activities of these enzymes were examined after their incubation with sucrose. Alternate acceptor molecules were also incubated with the enzymes to study their consumption. LSs from Gluconobacter oxydans and Novosphingobium aromaticivorans synthesized fructooligosaccharides (FOSs) with up to 13 units in length. Alignment of their amino acid sequences and substrate docking with homology models identified structural elements causing differences in their product spectra. Raffinose, over sucrose, was the preferred donor molecule for the LS from Vibrio natriegens, N. aromaticivorans, and Paraburkolderia graminis. The LSs examined were found to have wide acceptor promiscuity, utilizing monosaccharides, disaccharides, and two alcohols to a high degree.


Subject(s)
Fructans/chemistry , Fructose/chemistry , Gluconobacter oxydans/enzymology , Hexosyltransferases/chemistry , Oligosaccharides/chemistry , Sphingomonadaceae/enzymology , Amino Acid Sequence , Binding Sites , Biocatalysis , Burkholderiaceae/chemistry , Burkholderiaceae/enzymology , Fructans/biosynthesis , Fructose/metabolism , Gene Expression , Gluconobacter oxydans/chemistry , Hexosyltransferases/genetics , Hexosyltransferases/metabolism , Humans , Kinetics , Molecular Docking Simulation , Oligosaccharides/biosynthesis , Prebiotics/analysis , Protein Binding , Protein Conformation , Raffinose/chemistry , Raffinose/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Alignment , Sphingomonadaceae/chemistry , Structural Homology, Protein , Substrate Specificity , Sucrose/chemistry , Sucrose/metabolism , Vibrio/chemistry , Vibrio/enzymology
8.
Biomed Mater ; 15(5): 055018, 2020 08 28.
Article in English | MEDLINE | ID: mdl-32438354

ABSTRACT

Tissue regeneration often requires the use of biocompatible resorbable scaffolds to support the ingrowth of cells from neighboring tissues into a localized tissue defect. Such scaffolds must possess surface molecular cues that stimulate cells to populate the device, the first necessary condition for the formation of a healthy tissue. Chitosan is a natural polymer that has long been tested in biomedical applications because of its high biocompatibility, which can be further increased by modifying its formulation, e.g. adding D-(+) raffinose. We used this formulation in an ad hoc designed 3D printer to create regularly ordered scaffolds, which we then enriched with type IV collagen, an isoform of collagen that is exclusively found in basement membranes. Human epithelial A549 cells were then seeded on control scaffolds or on scaffolds coated with collagen, which was precipitated, or on scaffolds first collagenized and then exposed to either UVB or UVC radiation. Observations by the transmission light microscope, confocal microscope after staining with calcein-AM/propidium iodide, and by environmental scanning electron microscope revealed that collagen-enriched UV-treated scaffolds promoted the attachment of a higher number of cells, which covered a more extensive area of the scaffold, as also confirmed by alamar blue viability assay. Together these data confirm that coating 3D-printed scaffolds made of D-(+) raffinose-modified chitosan with type IV collagen and exposing them to UV light sensibly increases the cell compatibility of scaffolds, making them a better candidate to serve as a tool for the regeneration of epithelia.


Subject(s)
Biocompatible Materials/chemistry , Chitosan/chemistry , Collagen Type IV/chemistry , Epithelial Cells/metabolism , Printing, Three-Dimensional , Raffinose/chemistry , Tissue Scaffolds/chemistry , A549 Cells , Cell Adhesion , Coated Materials, Biocompatible/chemistry , Collagen/chemistry , Fluoresceins/chemistry , Humans , Materials Testing , Microscopy, Confocal , Polymers/chemistry , Propidium/chemistry , Regeneration , Temperature , Tissue Engineering
9.
Int J Biol Macromol ; 150: 1249-1257, 2020 May 01.
Article in English | MEDLINE | ID: mdl-31739012

ABSTRACT

An α-galactosidase designated as TAG was purified from the dried fruit bodies of Tremella aurantialba with 182.5-fold purification. The purification procedure involved ion exchange chromatography on Q-sepharose, DEAE-Cellulose, and Mono Q and gel filtration by FPLC on Superdex 75. The purified α-galactosidase was a monomeric protein with a molecular mass of 88 kDa. The optimal pH of TAG was 5.0 and more than 60% of the original enzyme activity remained at pH 2.0 and 3.0. Its optimal temperature was 54 °C with good thermo-stability, 30.8% of the original activity was retained after exposure to a temperature of 70 °C for 1 h. The metal ions Hg2+, Cu2+, Fe3+ and Mg2+ strongly inhibited the enzyme activity. The enzyme activity was found to be inhibited by N-bromosuccinimide indicating that tryptophan was essential to the catalytic activity of α-galactosidase. The enzyme completely hydrolysed stachyose and partially hydrolysed raffinose to galactose at 50 °C within 6 h as detected by thin layer chromatography and the dinitrosalicylic acid method and the content of reducing sugar reached 4.36 mg/mL.


Subject(s)
Basidiomycota/enzymology , Fungal Proteins , Oligosaccharides/chemistry , Raffinose/chemistry , alpha-Galactosidase , Enzyme Stability , Fungal Proteins/chemistry , Fungal Proteins/isolation & purification , Hot Temperature , Hydrolysis , Metals/chemistry , alpha-Galactosidase/chemistry , alpha-Galactosidase/isolation & purification
10.
Int J Biol Macromol ; 147: 1089-1098, 2020 Mar 15.
Article in English | MEDLINE | ID: mdl-31739059

ABSTRACT

Levan nanoparticles formation is a complicated phenomenon involving simultaneously polymeric reaction kinetics and nanoparticles self-assembly theory. These phenomena are studied in this work with experimental and computational methodologies. Specifically, the effect of different parameters on levan kinetics and nanoparticles production in a cell-free system environment have been studied. Results point out that 37 °C is the best temperature for synthesizing levan as well as the existence of a substrate inhibition effect for polymeric reaction. This work also highlights that raffinose can be used for producing and that an increase on the ratio enzyme-substrate increases the velocity of conversion. However, the previous experimental conditions did not produce an important effect on self-assembly formed levan nanoparticles (always 110 nm) as long as the required levan concentration (CAC) for nanoparticles reorganization is achieved. To have a better understanding of these results, a model was developed to explain numerically levan kinetics and nanoparticle self-assembly. This model was built by taking into account enzyme poisoning effect (also demonstrated experimentally) and a diffusion limited cluster model for the aggregation phenomenon. Simulation results fit properly experimental data and catalytic parameters as well as predicting accurately the value of CAC for producing its reorganization into nanoparticles by self-assembly.


Subject(s)
Fructans/chemistry , Nanoparticles/chemistry , Sugars/chemistry , Adenosine Triphosphate/chemistry , Bacillus subtilis , Carbohydrate Metabolism , Computer Simulation , Diffusion , Glucose/chemistry , Kinetics , Lactose/chemistry , Light , Particle Size , Polymers/chemistry , Raffinose/chemistry , Sucrose/chemistry , Temperature
11.
PLoS One ; 14(12): e0226183, 2019.
Article in English | MEDLINE | ID: mdl-31825976

ABSTRACT

The recent clinical application of perfusion technology for the machine preservation of donation after cardiac death (DCD) grafts has some advantages. Oxygenation has been proposed for the preservation of DCD liver grafts. The aim of this study is to clarify whether the use of HbV-containing preservation solution during the subnormothermic machine perfusion (SNMP) of the liver graft improves the graft function of DCD porcine livers in an ex vivo reperfusion model. Pig livers were excised after 60 minutes of warm ischemic time and were preserved under one of three preservation conditions for 4 hours. The preservation conditions were as follows: 4°C cold storage (CS group; N = 5), Hypothermic machine preservation (HMP) with UW gluconate solution (HMP group; N = 5), SNMP (21°C) with UW gluconate solution (SNMP group; N = 5), SNMP (21°C) with HbVs (Hb; 1.8 mg/dl) perfusate (SNMP+HbV group; N = 5). Autologous blood perfusion was performed for 2 hours in an isolated liver reperfusion model (IRM). The oxygen consumption of the SNMP and SNMP+HbV group was higher than the HMP groups (p < 0.05). During the reperfusion, the AST level in the SNMP+HbV group was lower than that in the CS, HMP and SNMP groups. The changes in pH after reperfusion was significantly lower in SNMP+HbV group than CS and HMP groups. The ultrastructural findings indicated that the mitochondria of the SNMP+HbV group was well maintained in comparison to the CS, HMP and SNMP groups. The SNMP+HbVs preservation solution protected against metabolic acidosis and preserved the liver function after reperfusion injury in the DCD liver.


Subject(s)
Hemoglobins/chemistry , Liver/pathology , Models, Animal , Organ Preservation/methods , Oxygen/chemistry , Adenosine/chemistry , Allopurinol/chemistry , Animals , Aspartate Aminotransferases/metabolism , Female , Glutathione/chemistry , Hemoglobins/metabolism , Hepatic Artery/physiology , Humans , Hydrogen-Ion Concentration , Insulin/chemistry , Lactic Acid/metabolism , Liver/metabolism , Liver Transplantation , Mitochondria/ultrastructure , Organ Preservation/instrumentation , Organ Preservation Solutions/chemistry , Oxygen/metabolism , Oxygen Consumption , Raffinose/chemistry , Swine , Temperature
12.
J Colloid Interface Sci ; 556: 616-627, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31494392

ABSTRACT

HYPOTHESIS: The development of functional and nutritional surfactants for the food industry remains a subject of great interest. Herein, therefore, we report on the design and synthesis of novel trisaccharide (raffinose) monoester-based surfactants in the expectation that they would display functional properties superior to certain disaccharide-based, commercially-deployed emulsifiers and thus have potential for industrial applications. EXPERIMENTS: The title esters were prepared by enzymatic methods and their properties as surfactants evaluated through determination of their HLB values, water solubilities, CMCs, foamabilities and foaming stabilities as well as through investigation of their impacts on the stability of oil-in-water emulsions over a range of storage times and under certain other conditions. FINDINGS: The emulsifying properties of 6-O-acylraffinose esters are dictated, in large part, by the length of the associated alkyl chains. The results of storage and environmental stress experiments revealed that the increasing length of alkyl chains enhances the stability of the derived emulsions. All the raffinose ester-stabilized oil-in-water emulsions displayed stratification effects under strongly acidic conditions (pH ≤ 4) or at high ionic strength (≥300 mM) while possessing reasonable resistance to variations in temperature. As such, a number of the raffinose monoesters showed greater stability to environmental stress than their commercially-deployed and sucrose-based counterparts. The structure-property profiles established through the present study provide a definitive guide for the development of raffinose esters as novel emulsifiers, particularly in the food industry.


Subject(s)
Emulsifying Agents , Fatty Acids/chemistry , Lipase/chemistry , Raffinose/chemistry , Emulsifying Agents/chemical synthesis , Emulsifying Agents/chemistry , Esters/chemical synthesis , Esters/chemistry , Molecular Structure
13.
Mol Biotechnol ; 61(9): 633-649, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31177409

ABSTRACT

Galactose oxidase catalyzes a two-electron oxidation, mainly from the C6 hydroxyl group of D-galactose, with the concomitant reduction of water to hydrogen peroxide. This enzyme is secreted by Fusarium species and has several biotechnological applications. In this study, a screening of galactose oxidase production among species of the Fusarium fujikuroi species complex demonstrated Fusarium subglutinans to be the main producer. The truncated F. subglutinans gaoA gene coding for the mature galactose oxidase was expressed from the prokaryotic vector pTrcHis2B in the E. coli Rosetta™ (DE3) strain. The purified recombinant enzyme presented temperature and pH optima of 30 °C and 7.0, respectively, KM of 132.6 ± 18.18 mM, Vmax of 3.2 ± 0.18 µmol of H2O2/min, kcat of 12,243 s-1, and a catalytic efficiency (kcat/KM) of 9.2 × 104 M-1 s-1. In the presence of 50% glycerol, the enzyme showed a T50 of 59.77 °C and was stable for several hours at pH 8.0 and 4 °C. Besides D-(+)-galactose, the purified enzyme also acted against D-(+)-raffinose, α-D-(+)-melibiose, and methyl-α-D-galactopyranoside, and was strongly inhibited by SDS. Although the F. subglutinans gaoA gene was successfully expressed in E. coli, its endogenous transcription was not confirmed by RT-PCR.


Subject(s)
Fusarium/enzymology , Galactose Oxidase/metabolism , Galactose/chemistry , Recombinant Proteins/metabolism , Amino Acid Sequence , Cloning, Molecular , Escherichia coli/genetics , Escherichia coli/metabolism , Fusarium/chemistry , Galactose/metabolism , Galactose Oxidase/chemistry , Galactose Oxidase/genetics , Gene Expression , Genetic Vectors/chemistry , Genetic Vectors/metabolism , Hydrogen-Ion Concentration , Melibiose/chemistry , Melibiose/metabolism , Methylgalactosides/chemistry , Methylgalactosides/metabolism , Models, Molecular , Oxidation-Reduction , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Raffinose/chemistry , Raffinose/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Sequence Alignment , Sequence Homology, Amino Acid , Substrate Specificity , Temperature
14.
PLoS One ; 14(5): e0216546, 2019.
Article in English | MEDLINE | ID: mdl-31091286

ABSTRACT

Copper radical alcohol oxidases belonging to auxiliary activity family 5, subfamily 2 (AA5_2) catalyze the oxidation of galactose and galactosides, as well as aliphatic alcohols. Despite their broad applied potential, so far very few AA5_2 members have been biochemically characterized. We report the recombinant production and biochemical characterization of an AA5_2 oxidase from Penicillium rubens Wisconsin 54-1255 (PruAA5_2A), which groups within an unmapped clade phylogenetically distant from those comprising AA5_2 members characterized to date. PruAA5_2 preferentially oxidized raffinose over galactose; however, its catalytic efficiency was 6.5 times higher on glycolaldehyde dimer compared to raffinose. Deep sequence analysis of characterized AA5_2 members highlighted amino acid pairs correlated to substrate range and conserved within the family. Moreover, PruAA5_2 activity spans substrate preferences previously reported for AA5 subfamily 1 and 2 members, identifying possible functional overlap across the AA5 family.


Subject(s)
Cloning, Molecular/methods , Oxidoreductases/genetics , Oxidoreductases/metabolism , Penicillium/enzymology , Raffinose/chemistry , Fungal Proteins/genetics , Fungal Proteins/metabolism , Galactose/chemistry , Galactosides/chemistry , High-Throughput Nucleotide Sequencing , Oxidation-Reduction , Penicillium/genetics , Phylogeny , Protein Engineering , Recombinant Proteins/metabolism , Sequence Analysis, Protein
15.
J Sci Food Agric ; 99(10): 4748-4760, 2019 Aug 15.
Article in English | MEDLINE | ID: mdl-30932192

ABSTRACT

BACKGROUND: Cross-linked enzyme aggregates (CLEAs) of α-galactosidase, partially purified from maize (Zea mays) flour, were prepared. The impact of various parameters on enzyme activity was examined to optimize the immobilization procedure. Biochemical characterization of the free and immobilized enzyme was carried out. Stability (thermal, pH, storage and operational stability) and reusability tests were performed. The potential use of the free enzyme and the CLEAs in hydrolysis processes of raffinose-type oligosaccharides present in soymilk was investigated. RESULTS: α-galactosidase CLEAs were prepared with 47% activity recovery under optimum conditions [1:5 (v/v) enzyme solution:saturated ammonium sulfate solution ratio; 7.5 mg protein and 0.1% (v/v) glutaraldehyde, 6 h, 4 °C, 150 rpm]. α-galactosidase CLEAs exhibited increased stability in comparison to the free enzyme. The CLEAs and the free enzyme showed a maximum activity at 40°C and their optimal pH values were5.5 and 6.0, respectively. Kinetic constants (KM , Vmax and kcat ) were calculated for the free enzyme and the CLEAs in the presence of p-nitrophenyl-α-d-galactopyranoside, stachyose, melibiose and raffinose. The effect of various chemicals and sugars on enzyme activity showed that both enzyme forms were significantly inhibited by HgCl2 and galactose. The CLEAs hydrolyzed 85% of raffinose and 96% of stachyose. CONCLUSION: The α-galactosidase CLEAs, with their satisfactory enzymatic characteristics, have much potential for use in the food and feed industry. © 2019 Society of Chemical Industry.


Subject(s)
Oligosaccharides/chemistry , Raffinose/chemistry , Soy Milk/chemistry , alpha-Galactosidase/chemistry , Biocatalysis , Cross-Linking Reagents/chemistry , Enzyme Stability , Enzymes, Immobilized/chemistry , Galactose/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Kinetics , Temperature
16.
Int J Biol Macromol ; 131: 1138-1146, 2019 Jun 15.
Article in English | MEDLINE | ID: mdl-30981775

ABSTRACT

Raffinose family oligosaccharides (RFOs) negatively affect nutritional value of legume-derived food and feed. It has been challenging to develop a high performance α-galactosidase excelled on catalytic efficiency, thermostability, pH stability and protease-resistance that could efficiently hydrolyze RFOs. In this study, the first GH family 27 α-galactosidase gene from Irpex lacteus was cloned. The gene had an open reading frame of 1314 bp interrupted by 12 introns. The recombinant α-galactosidase expressed in Pichia pastoris (rILgalA) had an apparent molecular mass of 64 kDa and was highly N-glycosylated. rILgalA was maximally active at pH 4.8 and 70 °C. It was stable over a broad pH range of 3-11, retained 90% of its activity after incubation at 60 °C for 10 h and exhibited strong resistance to digestive proteases. Unlike many other α-galactosidases, rILgalA was hyperactive on RFOs. Its specific activities toward melibiose, raffinose and stachyose were 644, 755 and 833 U mg-1, respectively. The corresponding Kcat/Km values were 120, 130 and 180 mM-1 s-1, which were the highest among reported α-galactosidases. rILgalA almost completely hydrolyzed raffinose and stachyose in soymilk at 60 °C in 30 min. These superior properties would make rILgalA an ideal remover of RFOs in food and feed industries.


Subject(s)
Basidiomycota/enzymology , Basidiomycota/genetics , Oligosaccharides/chemistry , Raffinose/chemistry , Soy Milk/chemistry , alpha-Galactosidase/chemistry , alpha-Galactosidase/genetics , Amino Acid Sequence , Cloning, Molecular , Enzyme Activation , Gene Expression , Hydrogen-Ion Concentration , Hydrolysis , Kinetics , Recombinant Proteins , Sequence Analysis, DNA , Substrate Specificity , alpha-Galactosidase/isolation & purification , alpha-Galactosidase/metabolism
17.
J Food Sci ; 83(11): 2827-2839, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30320406

ABSTRACT

Amorphous sucrose is a component of many food products but is prone to crystallize over time, thereby altering product quality and limiting shelf-life. A systematic investigation was conducted to determine the effects of two monosaccharides (glucose and fructose), five disaccharides (lactose, maltose, trehalose, isomaltulose, and cellobiose), and two trisaccharides (maltotriose and raffinose) on the stability of amorphous sucrose in lyophilized two-component sucrose-saccharide blends exposed to different relative humidity (RH) and temperature environmental conditions relevant for food product storage. Analyses included X-ray diffraction, differential scanning calorimetry, microscopy, and moisture content determination, as well as crystal structure overlays. All lyophiles were initially amorphous, but during storage the presence of an additional saccharide tended to delay sucrose crystallization. All samples remained amorphous when stored at 11% and 23% RH at 22 °C, but increasing the RH to 33% RH and/or increasing the temperature to 40 °C resulted in variations in crystallization onset times. Monosaccharide additives were less effective sucrose crystallization inhibitors relative to di- and tri-saccharides. Within the group of di- and tri-saccharides, effectiveness depended on the specific saccharide added, and no clear trends were observed with saccharide molecular weight and other commonly studied factors such as system glass transition temperature. Molecular level interactions, as evident in crystal structure overlays of the added saccharides and sucrose and morphological differences in crystals formed, appeared to contribute to the effectiveness of a di- or tri-saccharide in delaying sucrose crystallization. In conclusion, several di- and tri-saccharides show promise for use as additives to delay the crystallization kinetics of amorphous sucrose during storage at moderate temperatures and low RH conditions. PRACTICAL APPLICATION: Amorphous sucrose is desirable in a variety of food products, wherein crystallization can be problematic for texture and shelf-life. This study documents how different mono-, di-, and tri-saccharides influence the crystallization of sucrose. Monosaccharide additives were less effective sucrose crystallization inhibitors relative to di- and tri-saccharides. These findings increase the understanding of how different mono-, di-, and tri-saccharide structures and their solid-state properties influence the crystallization of amorphous sucrose and show that several di- and tri-saccharides have potential for use as sucrose crystallization inhibitors.


Subject(s)
Polysaccharides/chemistry , Sucrose/chemistry , Calorimetry, Differential Scanning , Cellobiose/chemistry , Crystallization , Food Analysis , Isomaltose/analogs & derivatives , Isomaltose/chemistry , Lactose/chemistry , Maltose/chemistry , Microscopy, Electron, Scanning , Molecular Structure , Raffinose/chemistry , Transition Temperature , Trehalose/chemistry , Trisaccharides/chemistry , Viscosity , X-Ray Diffraction
18.
Transplantation ; 102(10): e404-e412, 2018 10.
Article in English | MEDLINE | ID: mdl-30247450

ABSTRACT

BACKGROUND: Cold ischemia-reperfusion injury is unavoidable during organ transplantation, and prolonged preservation is associated with poorer function recovery. Cardiotrophin-1 (CT-1) is an IL-6 family cytokine with cytoprotective properties. This preclinical study in rats tested whether CT-1 mitigates cold renal ischemia-reperfusion injury in the context of the transplantation of long-time preserved kidneys. METHODS: Kidneys were flushed with cold (4°C) University of Wisconsin solution containing 0.2 µg/mL CT-1 and stored for several periods of time at 4°C in the same solution. In a second approach, kidneys were first cold-preserved for 6 hours and then were perfused with University of Wisconsin solution containing CT-1 (0, 16, 32, or 64 µg/mL) and further cold-preserved. Organ damage markers were measured in the kidneys at the end of the storage period. For renal transplantation, recipient consanguineous Fischer rats underwent bilateral nephrectomy and received a previously cold-preserved (24 hours) kidney as described above. Survival and creatinine clearance were monitored over 30 days. RESULTS: Cardiotrophin-1 in perfusion and preservation fluids reduced oxidative stress markers (superoxide anion and inducible nitric oxide synthase), inflammation markers (NF-κB and tumor necrosis factor-α), and vascular damage (vascular cell adhesion molecule-1) and activated leukemia inhibitory factor receptor and STAT-3 survival signaling. Transplantation of kidneys cold-preserved with CT-1 increased rat survival and renal function (ie, lower plasma creatinine and higher creatinine clearance) and improved kidney damage markers after transplantation (ie, lower superoxide anion, tumor necrosis factor-α, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 and higher NF-κB). CONCLUSIONS: Cardiotrophin-1 represents a novel therapeutic strategy to reduce ischemia-reperfusion and cold preservation injury to rescue suboptimal kidneys and, consequently, to improve the clinical outcomes of renal transplantation.


Subject(s)
Cytokines/therapeutic use , Kidney Transplantation/adverse effects , Organ Preservation/methods , Reperfusion Injury/prevention & control , Tissue and Organ Harvesting/methods , Adenosine/chemistry , Allografts/blood supply , Allografts/drug effects , Allopurinol/chemistry , Animals , Cold Ischemia/adverse effects , Cytokines/pharmacology , Disease Models, Animal , Glutathione/chemistry , Graft Survival/drug effects , Humans , Insulin/chemistry , Kidney/blood supply , Kidney/drug effects , Kidney Function Tests , Kidney Transplantation/methods , Male , Nephrectomy , Organ Preservation Solutions/chemistry , Perfusion/methods , Raffinose/chemistry , Rats , Rats, Inbred F344 , Reperfusion Injury/etiology , Tissue and Organ Harvesting/adverse effects
19.
Acta Biochim Pol ; 65(3): 383-389, 2018.
Article in English | MEDLINE | ID: mdl-30188963

ABSTRACT

An acidic α-galactosidase designated as hemp seed α-galactosidase (HSG) was purified from hemp (Cannabis sativa L.) seeds. By means of chromatographic procedures which involved chromatography on the cation-exchangers CM-cellulose and SP-Sepharose, chromatography on the anion-exchangers DEAE-cellulose and Q-Sepharose, and gel filtration on Superdex 75 using fast protein liquid chromatography, HSG was purified to electrophoretic homogeneity. Results of SDS-PAGE and gel filtration on FPLC Superdex 75 revealed that the enzyme was a monomeric protein with a molecular weight of 38 kDa. Sequences of the inner peptides of the α-galactosidase obtained by MALDI-TOF-MS showed that HSG was a novel α-galactosidase since there was a little similarity to the majority of α-galactosidases recorded in the literature. A pH of 3.0 and a temperature of 50°C were optimal for the activity of the enzyme. The activity of HSG was inhibited by the chemical modification with N-bromosuccinimide (NBS) reagent. HSG contained 16 tryptophan residues and two tryptophan residues on the surface, which were crucial to the α-galactosidase activity. The heavy metal ions Cd2+, Cu2+, Hg2+ and Zn2+ inhibited its activity. The Km and Vmax for the hydrolysis of pNPGal (4-nitrophenyl α-D-galactopyranoside) were respectively 0.008 mM and 68 µM min-1 mg-1. HSG also catalyzed the hydrolysis of raffinose and other natural substrates. Hence the α-galactosidase possesses a tremendous potential for food and feed industries in the elimination of indigestible oligosaccharides from leguminous products.


Subject(s)
Cannabis/enzymology , Raffinose/isolation & purification , Seeds/enzymology , alpha-Galactosidase/chemistry , Bromosuccinimide/chemistry , Chromatography, Liquid/methods , Electrophoresis, Polyacrylamide Gel , Enzyme Inhibitors/pharmacology , Hot Temperature , Hydrogen-Ion Concentration , Hydrolysis , Metals, Heavy/pharmacology , Molecular Weight , Nitrophenylgalactosides/chemistry , Raffinose/chemistry , Spectrometry, Mass, Electrospray Ionization , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Tryptophan/analysis , alpha-Galactosidase/antagonists & inhibitors , alpha-Galactosidase/isolation & purification
20.
Anal Chem ; 90(10): 6001-6005, 2018 05 15.
Article in English | MEDLINE | ID: mdl-29701986

ABSTRACT

A major problem limiting reproducible use of liquid extraction surface analysis (LESA) array sampling of dried surface-deposited liquid samples is the unwanted spread of extraction solvent beyond the dried sample limits, resulting in unreliable data. Here, we explore the use of the Droplet Microarray (DMA), which consists of an array of superhydrophilic spots bordered by a superhydrophobic material giving the potential to confine both the sample spot and the LESA extraction solvent in a defined area. We investigated the DMA method in comparison with a standard glass substrate using LESA analysis of a mixture of biologically relevant compounds with a wide mass range and different physicochemical properties. The optimized DMA method was subsequently applied to urine samples from a human intervention study. Relative standard deviations for the signal intensities were all reduced at least 3-fold when performing LESA-MS on the DMA surface compared with a standard glass surface. Principal component analysis revealed more tight clusters indicating improved spectral reproducibility for a human urine sample extracted from the DMA compared to glass. Lastly, in urine samples from an intervention study, more significant ions (145) were identified when using LESA-MS spectra of control and test urine extracted from the DMA. We demonstrate that DMA provides a surface-assisted LESA-MS method delivering significant improvement of the surface extraction repeatability leading to the acquisition of more robust and higher quality data. The DMA shows potential to be used for LESA-MS for controlled and reproducible surface extraction and for acquisition of high quality, qualitative data in a high-throughput manner.


Subject(s)
Arginine/isolation & purification , Diphenhydramine/isolation & purification , Liquid-Liquid Extraction , Raffinose/isolation & purification , Rhodamines/isolation & purification , Taurine/isolation & purification , Vitamin B 12/isolation & purification , Arginine/chemistry , Arginine/urine , Diphenhydramine/chemistry , Diphenhydramine/urine , Healthy Volunteers , Humans , Hydrophobic and Hydrophilic Interactions , Male , Mass Spectrometry , Raffinose/chemistry , Raffinose/urine , Rhodamines/chemistry , Rhodamines/urine , Surface Properties , Taurine/chemistry , Taurine/urine , Vitamin B 12/chemistry , Vitamin B 12/urine
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