Scan Science and Technology
Contact Leading Edge Experts & Companies
Amadori Products
The Experts below are selected from a list of 1698 Experts worldwide ranked by ideXlab platform
Zbigniew Szewczuk – One of the best experts on this subject based on the ideXlab platform.
-
Intramolecularly stapled amphipathic peptides via a boron–sugar interaction
Chemical Communications, 2020Co-Authors: Monika Kijewska, Piotr Stefanowicz, Łukasz Jaremko, Mariusz Jaremko, Mateusz Waliczek, Angelika Czerwińska, Samah Al-harthi, Grzegorz Wołczański, Abdul-hamid Emwas, Zbigniew SzewczukAbstract:Amadori Products (deoxyfructosyllysine derivatives) that can selectively interact with phenylboronic acids and borate ions were synthesized. The intramolecular interactions between the fructosyl moiety and phenylboronic acid incorporated into various positions of the peptide chain were investigated using high-resolution mass spectrometry (HR–MS), circular dichroism (CD), and nuclear magnetic resonance (NMR).
-
DOI: 10.1007/s13361-014-0857-4 RESEARCH ARTICLE Selective Detection of Carbohydrates and Their Peptide Conjugates by ESI-MS Using Synthetic Quaternary Ammonium Salt Derivatives of Phenylboronic Acids
, 2016Co-Authors: Zbigniew SzewczukAbstract:Abstract. We present new tags based on the derivatives of phenylboronic acid and apply them for the selective detection of sugars and peptide-sugar conjugates in mass spectrometry. We investigated the binding of phenylboronic acid and its quaternary ammonium salt (QAS) derivatives to carbohydrates and peptide-derived Amadori Products by HR-MS and MS/MS experiments. The formation of complexes between sugar or sugar-peptide conjugates and synthetic tags was confirmed on the basis of the unique isotopic distribution resulting from the presence of boron atom. Moreover, incorporation of a quaternary ammonium salt dramatically improved the efficiency of ionization in mass spectrometry. It was found that the formation of a complex with phenylboronic acid stabilizes the sugar moiety in glycated peptides, resulting in simplification of the fragmentation pattern of peptide-derived Amadori Products. The obtained results suggest that derivatization of phenylboronic acid as QAS is a promising method for sensitive ESI-MS detection of carbohydrates and their conjugates formed by non-enzymatic glycation or glycosylation
-
Comparison of modification sites in glycated crystallin in vitro and in vivo
, 2016Co-Authors: Martyna Kielmas, Piotr Stefanowicz, Alicja Kluczyk, Monika Kijewska, Jolanta Oficjalska, Bożena Gołębiewska, Zbigniew SzewczukAbstract:Abstract Glycation ofα-crystallin is responsible for age- and diabetic-related cataracts, which are the main cause of blind-ness worldwide. We optimized the method of identification of lysine residues prone to glycation using the combination of LC-MS, isotopic labeling, and modified synthetic peptide standards with the glycated lysine derivative (Fmoc-Lys(i,i-Fru,Boc)-OH). The in vitro glycation of bovine lens α-crystallin was conducted by optimized method with the equi-molar mixture of [12C6]- and [ 13C6]D-glucose. The in vivo glycation was studied on human lens crystallin. The glycated protein was subjected to proteolysis and analyzed using LC-MS. The results of in vitro and in vivo glycation of α-crystallin reveal a different distribution of the modified lysine residues. More Amadori Products were detected as a result of the in vitro reaction due to forced glycation conditions. The developed method allowed us to identify the glycation sites in crystallin from eye lenses obtained from patients suffering from the cataract. We identified K166 in the A chain and K166 in the B chain of α-crystallin as major glycation sites during the in vitro reaction. We found also two in vivo glycated lysine residues: K92 in the B chain and K166 in the A chain, which are known as locations for Amadori Products. These modification sites were confirmed by the LC-MS experiment using two synthetic standards. This study demonstrates the applicability of the LC-MS methods com-bined with the isotopic labeling and synthetic peptide stan-dards for analysis of post-translational modifications in the biological material
Vincenzo Fogliano – One of the best experts on this subject based on the ideXlab platform.
-
the quantification of free Amadori compounds and amino acids allows to model the bound maillard reaction Products formation in soybean Products
Food Chemistry, 2018Co-Authors: Antonio Dario Troise, Vincenzo Fogliano, Markus Wiltafsky, Paola VitaglioneAbstract:The quantification of protein bound Maillard reaction Products (MRPs) is still a challenge in food chemistry. Protein hydrolysis is the bottleneck step: it is time consuming and the protein degradation is not always complete. In this study, the quantitation of free amino acids and Amadori Products (APs) was compared to the percentage of blocked lysine by using chemometric tools. Eighty thermally treated soybean samples were analyzed by mass spectrometry to measure the concentration of free amino acids, free APs and the protein-bound markers of the Maillard reaction (furosine, Ne-(carboxymethyl)-l-lysine, Ne-(carboxyethyl)-l-lysine, total lysine). Results demonstrated that Discriminant Analysis (DA) and Correlated Component Regression (CCR) correctly estimated the percent of blocked lysine in a validation and prediction set. These findings indicate that the measure of free markers reflects the extent of protein damage in soybean samples and it suggests the possibility to obtain rapid information on the quality of the industrial processes.
-
Evolution of protein bound Maillard reaction end-Products and free Amadori compounds in low lactose milk in presence of fructosamine oxidase i
Food Chemistry, 2016Co-Authors: Antonio Dario Troise, Martina Buonanno, Alberto Fiore, Simona Maria Monti, Vincenzo FoglianoAbstract:Thermal treatments and storage influence milk quality, particularly in low lactose milk as the higher concentration of reducing sugars can lead to the increased formation of the Maillard reaction Products (MRPs). The control of the Amadori Products (APs) formation is the key step to mitigate the Maillard reaction (MR) in milk. The use of fructosamine oxidases, (Faox) provided promising results. In this paper, the effects of Faox I were evaluated by monitoring the concentration of free and bound MRPs in low lactose milk during shelf life. Results showed that the enzyme reduced the formation of protein-bound MRPs down to 79% after six days at 37 °C. Faox I lowered the glycation of almost all the free amino acids resulting effective on basic and polar amino acids. Data here reported corroborate previous findings on the potentiality of Faox enzymes in controlling the early stage of the MR in foods.
-
Amadori Products formation in emulsified systems.
Food Chemistry, 2016Co-Authors: Antonio Dario Troise, Claire C. Berton-carabin, Vincenzo FoglianoAbstract:The formation of Amadori Products (APs) is the key step determining the development of the Maillard reaction (MR). The information on the chemical behaviour of the reaction between amino acids and reducing sugars in emulsions during thermal treatments is scanty and mainly focused on volatile compounds. The aim of this work was to investigate the formation of APs from glucose and two amino acids with different partition coefficients (phenylalanine and leucine) in emulsions. Two submicron oil-in-water (O/W) emulsions consisting of water, tricaprylin and Tween 20 were prepared, thermally treated and the formation of fructose-phenylalanine (Fru-Phe) and fructose-leucine (Fru-Leu) was monitored by mass spectrometry. The concentration of Fru-Phe in submicron emulsions was similar to that in water, while Fru-Leu was reduced up to 47% in the emulsions. These data indicated that partition coefficient of amino acids, determining the reactants location, can substantially influence the MR and the final quality of foods.
Antonio Dario Troise – One of the best experts on this subject based on the ideXlab platform.
-
the quantification of free Amadori compounds and amino acids allows to model the bound maillard reaction Products formation in soybean Products
Food Chemistry, 2018Co-Authors: Antonio Dario Troise, Vincenzo Fogliano, Markus Wiltafsky, Paola VitaglioneAbstract:The quantification of protein bound Maillard reaction Products (MRPs) is still a challenge in food chemistry. Protein hydrolysis is the bottleneck step: it is time consuming and the protein degradation is not always complete. In this study, the quantitation of free amino acids and Amadori Products (APs) was compared to the percentage of blocked lysine by using chemometric tools. Eighty thermally treated soybean samples were analyzed by mass spectrometry to measure the concentration of free amino acids, free APs and the protein-bound markers of the Maillard reaction (furosine, Ne-(carboxymethyl)-l-lysine, Ne-(carboxyethyl)-l-lysine, total lysine). Results demonstrated that Discriminant Analysis (DA) and Correlated Component Regression (CCR) correctly estimated the percent of blocked lysine in a validation and prediction set. These findings indicate that the measure of free markers reflects the extent of protein damage in soybean samples and it suggests the possibility to obtain rapid information on the quality of the industrial processes.
-
Encapsulation of ascorbic acid promotes the reduction of Maillard reaction Products in UHT milk
Food & Function, 2016Co-Authors: Antonio Dario Troise, Daniele Vitiello, Catherine Tsang, Alberto FioreAbstract:The presence of amino groups and carbonyls renders fortified milk with ascorbic acid particularly susceptible to the reduction of available lysine and to the formation of Maillard reaction Products (MRPs), as Ne-(carboxyethyl)-L-lysine (CEL), Ne-(carboxymethyl)-L-lysine (CML), Amadori Products (APs) and off-flavors. A novel approach was proposed to control the Maillard reaction (MR) in fortified milk: ascorbic acid was encapsulated in a lipid coating and the effects were tested after a lab scale UHT treatment. Encapsulation promoted a delayed release of ascorbic acid and a reduction in the formation of MRPs. Total lysine increased up to 45% in milk with encapsulated ascorbic acid, while reductions in CML, CEL and furosine ranged from 10% to 53% compared with control samples. The effects were also investigated towards the formation of amide-AGEs (advanced glycation end Products) by high resolution mass spectrometry (HRMS) revealing that several mechanisms coincide with the MR in the presence of ascorbic acid.
-
Evolution of protein bound Maillard reaction end-Products and free Amadori compounds in low lactose milk in presence of fructosamine oxidase i
Food Chemistry, 2016Co-Authors: Antonio Dario Troise, Martina Buonanno, Alberto Fiore, Simona Maria Monti, Vincenzo FoglianoAbstract:Thermal treatments and storage influence milk quality, particularly in low lactose milk as the higher concentration of reducing sugars can lead to the increased formation of the Maillard reaction Products (MRPs). The control of the Amadori Products (APs) formation is the key step to mitigate the Maillard reaction (MR) in milk. The use of fructosamine oxidases, (Faox) provided promising results. In this paper, the effects of Faox I were evaluated by monitoring the concentration of free and bound MRPs in low lactose milk during shelf life. Results showed that the enzyme reduced the formation of protein-bound MRPs down to 79% after six days at 37 °C. Faox I lowered the glycation of almost all the free amino acids resulting effective on basic and polar amino acids. Data here reported corroborate previous findings on the potentiality of Faox enzymes in controlling the early stage of the MR in foods.