Digestibilnost β-laktoglobulina nakon njegovog unakrsnog povezivanja dejstvom lakaze iz Trametes versicolor i polifenola iz jabuke

beta-Lactoglobulin (BLG) is an important nutrient of dairy products and an important allergen in cow's milk allergy. The aim of this study was to investigate the potential of laccase to cross-link BLG in the presence of an apple phenolic extract (APE) and to characterize the obtained products for their digestibility by pepsin and pancreatin. The composition of the apple phenolics used for cross-linking was determined by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). The apple phenolic extract contained significant amounts of quercetin glycosides, catechins and chlorogenic acid. The laccase cross-linked BLG in the presence of apple phenolics. The polymerization rendered the protein insoluble in the reaction mixture. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of the cross-linking reaction mixture revealed a heterogeneous mixture of high molecular masses (cross-linked BLG), with a fraction of the BLG remaining monomeric. Enzymatic processing of BLG by laccase and apple polyphenols as mediators can decrease the biphasal pepsin pancreatin digestibility of the monomeric and cross-linked protein, thus decreasing its nutritional value. In addition, reduced BLG digestibility can decrease its allergenic potential. Apple polyphenols can find usage in the creation of new, more functional food products, designed to prevent obesity and hypersensitivity-related disorders.β-Laktoglobulin (BLG) je važan nutrijent mlečnih proizvoda i važan alergen kod alergija na kravlje mleko. Cilj ove studije je bilo ispitivanje potencijala lakaze da unakrsno poveže BLG u prisustvu fenolnog ekstrakta jabuke (APE), kao i karakterizacija dobijenih proizvoda sa aspekta njihove digestibilnosti pepsinom i pankreatinom. Kompozicija fenola jabuke korišćenih za unakrsno povezivanje određena je pomoću LC-ESI-MS. Fenolni ekstrakt jabuke sadrži znatne količine glikozida kvercetina, katehine i hlorogensku kiselinu. BLG je unakrsno povezan lakazom u prisustvu fenola jabuke, pri čemu je polimerizacija učinila BLG nerastvornim u reakcionoj smeši. SDS-PAGE analiza pokazala je da reakciona smeša sadrži heterogenu smešu velikih molekulskih masa (unakrsno povezan BLG), kao i deo zaostalog monomernog BLG. Enzimsko procesovanje BLG lakazom, u prisustvu polifenola jabuke kao medijatora, može smanjiti bifaznu pepsin-pankreatinsku digestibilnost kako monomernog, tako i unakrsno povezanog BLG, i na taj način smanjiti njegovu nutritivnu vrednost. Takođe, smanjena digestibilnost BLG može smanjiti njegov alergeni potencijal. Polifenoli jabuke mogu se koristiti za kreiranje novih, funkcionalnijih prehrambenih proizvoda, dizajniranih za prevenciju kako gojaznosti, tako i bolesti vezanih za preosetljivost

Sojne razlike u toksičnosti antagoniste vitamina K varfarina kod pacova

Warfarin (3-(alpha-acetonylbenzy1)-4-hydroxy coumarin) is a vitamin K (VK) antagonist that inhibits vitamin K-dependent (VKD) processes, such as blood coagulation. It also exerts an influence on some non-VKD-related activities. In this study, the effect of sub-acute (30-day) oral warfarin (2 and 1 mg L-1) intake on hematological parameters was examined in two rat strains, Albino Oxford (AO) and Dark Agouti (DA), that differ in their sensitivity to certain chemicals. Greater susceptibility to the anticoagulant effect of 2 mg L-1 of warfarin was observed in AO rats and was associated with an increase in the relevant hematological parameters in this strain. Although both strains responded to 2 mg L-1 of warfarin with quantitative changes in the peripheral blood leukocytes, differential bone marrow and lung responses were observed. Strain-related differences in the pro-inflammatory activity of peripheral blood granulocytes and in mononuclear cell IFN-gamma production were observed. Recognition of differences in quantitative and qualitative effects of oral warfarin on processes other than hemostasis might be of relevance for those humans who are on warfarin therapy.Varfarin (3-α-acetonilbenzil)-4–hidroksikumarin) je antagonist vitamina K (VK) koji inhibira procese zavisne od ovog vitamina, uključujući koagulaciju krvi. Osim toga, on ispoljava i aktivnosti koje ne zavise od vitamina K kao što su anti-tumorska i imunomodulatorna aktivnost. U ovom radu je ispitan efekat subakutnog (30 dana) oralnog unosa varfarina na hematološke parametre i aktivnost leukocita periferne krvi kod dva soja pacova Albino Oxford (AO) i Dark Agouti (DA) koji se raz- likuju u osetljivosti na iste hemijske agense. Kod jedinki AO soja zapažena je veća smrtnost nakon konzumiranja doze od 4 mg L–1 kao i veća osetljivost na antikoagulantno dejstvo varfarina pri nižim dozama (2 mg L–1) koje je praćeno povećanjem nekih hematoloških parametara. Iako kod jedinki oba soja dolazi do povećanja broja neutrofilnih leukocita periferne krvi pri dozi od 2 mg L–1, promene u osnovnim proinflamatornim aktivnostima ovih ćelija su zapažene samo kod jedinki DA soja. Promene u broju neutrofilnih leukocita u krvi DA jedinki su praćene povećanjem broja granulocitnih prekursora u koštanoj srži, dok prisustvo neutrofila u plućima AO jedinki ukazuje na razmenu ćelija između periferne krvi i plućnog intravaskularnog pula ćelija. Diferencijalne sojno–zavisne promene u aktivnosti mononuklearnih ćelija periferne krvi su takođe zapažene. Razlike u efektu oralno unetog varfarina mogu da imaju implikacije za osobe na oralnoj varfarinskoj terapiji

Comparison of 2D proteomic maps revealed properties of Ambrosia artemisiifolia sub-pollen particles accounting for more severe asthma symptoms than its whole pollen grains

Aims and scopes: It is known that sub-pollen particles (SPP) cause more severe symptoms of asthma than its whole pollen grain counterparts, due to its smaller size and ability to penetrate deeper into the lungs. To reveal other possible causes of such more severe asthma symptoms induced by Ambrosia artemisiifolia SPP, its sub-pollen particle and pollen grain proteomes were characterized and compared. Experimental description: Protein extract of short ragweed (Ambrosia artemisiifolia) pollen and its SPP were prepared and subjected to denaturing 2-D electrophoresis. Pollen proteome spots were excised a er colloidal coomassie blue brillinat (cCBB) staining and in gel digested for liquid chromatography coupled with high resolution LTQ Orbitrap XL hybrid mass spectrometry. Parallel to that, cCBB stained gels were analyzed and quanti ed with laser scanner Typhoon 7000 series and Image 2D Master Platinum 7.0 soware (GE Healthcare, USA). Results: ere is statistically signi cant di erence between the contents of major allergen Amb a 1.05 subgroup in the ragweed whole pollen grains and SPP, the latter being richer in Amb a 1.05 (2 times), in major allergen Amb a 11 (5 times), in minor allergens Amb a 4 (7 times) and Amb a 6 (4 times). e 30 kDa basic antigen group in SPP (8 times more abundant) needs further investigation. sia artemisiifolia allergens, Amb a 1.05 and Amb a 11, minor allergens Amb a 4 and Amb a 6 which could contribute to more severe asthma symptoms caused by SPP

Green tea catechins of food, supplements facilitate pepsin digestion of major food allergens, but hampers their digestion if oxidized by phenol oxidase

The in vitro gastric digestion of several food allergens (beta-lactoglobulin (BLG), alpha-lactalbumin (LA) and peanut allergens (PE)) in the presence of a catechin-enriched polyphenol extract of green tea (GTC), oxidized polyphenols and phenol oxidase processed food allergens and GTC was investigated. Pepsin-resistant proteins, such as BLG, major peanut allergens, Ara h 1 and Ara h 2, degrade faster in the presence of catechin-enriched green tea polyphenols. Phenol oxidase polymerized GTC affected adversely protein digestion of BLG and LA, but not digestion of PE proteins. Protecting effect of polyphenols correlated well with the ability of proteins to form insoluble complexes with oxidized catechins. Cross-linking of proteins and polyphenols further extended the half-lives of BLG and LA in the in vitro digestion by pepsin. Catechin-enriched green tea polyphenols of food supplements facilitate pepsin digestion of major food allergens, but hamper their digestion if oxidized and polymerized by phenol oxidase. (c) 2012 Elsevier Ltd. All rights reserved

Peanut protein structure, polyphenol content and immune response to peanut proteins in vivo are modulated by laccase

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Digestibility and allergenicity of beta-lactoglobulin following laccase-mediated cross-linking in the presence of sour cherry phenolics

beta-Lactoglobulin (BLG) is an important nutrient of dairy products, but it represents a serious health risk in patients allergic to milk. Sour cherry (Prunus cerasus L) extract (SCE) is frequently added as a natural food colour in composite foods, such as fruit yogurt, ice creams, frappes and milkshakes. The aim of this study was to investigate the potential of laccase to cross-link BLG in the presence of an SCE and to characterise the obtained products for their bioactivity. Laccase cross-linked BLG in the presence of sour cherry phenolics. In a basophil-activation assay, the allergenicity of the cross-linked protein was shown to decrease in all nine cow's milk-allergic patients, while digestibility of the remaining monomeric BLG in simulated conditions of the gastrointestinal tract increased. Tryptic peptides became immediately available in BLG treated by laccase and laccase/SCE. The hydrolysates obtained by trypsin digestion of BLG/laccase/SCE showed an increase of 57% in radical-scavenging activity, compared to the control BLG. Enzymatic processing and usage of natural phenolic extracts as mediators of enzymatic reaction may improve BLG safety and the availability of peptides following digestion, while conserving its bioactivity

Composition of polyphenol and polyamide compounds in common ragweed (Ambrosia artemisiifolia L.) pollen and sub-pollen particles

Phenolic composition of Ambrosia artemisiifolia L. pollen and sub-pollen particles (SPP) aqueous extracts was determined, using a novel extraction procedure. Total phenolic and flavonoid content was determined, as well as the antioxidative properties of the extract. Main components of water-soluble pollen phenolics are monoglycosides and malonyl-mono- and diglycosides of isorhamnetin, quercetin and kaempferol, while spermidine derivatives were identified as the dominant polyamides. SPP are similar in composition to pollen phenolics (predominant isorhamnetin and quercetin monoglycosides), but lacking small phenolic molecules ( lt 450 Da). Ethanol-based extraction protocol revealed one-third lower amount of total phenolics in SPP than in pollen. For the first time in any pollen species, SPP and pollen phenolic compositions were compared in detail, with an UHPLC/ESI-LTQ-Orbitrap-MS-MS approach, revealing the presence of spermidine derivatives in both SPP and pollen, not previously reported in Ambrosia species. (C) 2014 Elsevier Ltd. All rights reserved