Εξειδίκευση τύπου :	Άρθρο σε επιστημονικό περιοδικό
Τίτλος:	Unravelling the structural heterogeneity and diversity in rheological behavior of alkali-extractable wheat bran arabinoxylans using ammonia pretreatment
Δημιουργός/Συγγραφέας:	Mouzakitis, Christos-Konstantinos Kotsiou, Kali Pontikakos, Georgios Matzapetakis, Manolis [EL] Ζερβού, Μαρία[EN] Zervou, Maria Biliaderis, Costas G. Lazaridou, Athina
Χορηγός :	European Union
Ημερομηνία:	2024
Γλώσσα:	Αγγλικά
ISSN:	0268005X
DOI:	10.1016/j.foodhyd.2024.109888
Περίληψη:	The impact of ammonia solution (NH4OH) mild pretreatment (pH 9.5, 25 °C/0.5–2 h), followed by sodium hydroxide extraction (0.1 M NaOH, 60 °C/1–4 h), on the wheat bran (WB) arabinoxylan (AX) extractability, the molecular features of the isolated polysaccharides and their rheological behavior were investigated. AX isolates, obtained from WB treated solely with NH4OH, exhibited lower Mw and a lower degree of xylan backbone substitution (arabinose/xylose ratio), compared to those obtained by combined alkali treatments (NH4OH/NaOH), as evaluated by HPLC-SEC-RI, FTIR and 1H NMR analyses. Swelling of bran cell walls, caused by NH4OH, resulted in crevices of the outer bran tissue layers, thus increasing AX extraction yields, as the ammonia pretreatment and NaOH extraction times were extended. 2D DOSY NMR experiments revealed the presence of individual populations exhibiting discrete diffusional characteristics, while in most cases, each population was further subdivided into two sub-populations composed mainly of chains of either monosubstituted or disubstituted anhydro-xylosyl residues, with the latter diffusing more slowly. The steady-shear viscosities of 4% aqueous AX dispersions were positively correlated primarily to the AX Mw, and secondarily to the arabinose/xylose ratio. Dynamic rheometry revealed that extraction only with NH4OH or water provided AX isolates capable of gelification due to oxidative coupling of feruloyl residues covalently attached on AX chains, as evidenced by FTIR, 1H NMR, and further confirmed by 2D DOSY NMR. Overall, these findings elucidated the structural heterogeneity of AX isolates obtained under varying alkali extraction regimes, along with their diversified rheological behavior.
Τίτλος πηγής δημοσίευσης:	Food Hydrocolloids
Τόμος/Κεφάλαιο:	151
Θεματική Κατηγορία:	[EL] Βιοχημεία[EN] Biochemistry [EL] Αναλυτική χημεία[EN] Analytical chemistry [EL] Φασματοσκοπία[EN] Spectroscopy [EL] Βιοτεχνολογία[EN] Biotechnology
Λέξεις-Κλειδιά:	wheat bran arabinoxylan molecular characteristics ammonia pretreatment 2D NMR spectroscopy 2D DOSY NMR spectroscopy FTIR spectroscopy arabinoxylan rheological properties
EU Grant:	Competitiveness, Entrepreneurship and Innovation, under the call RESEARCH – CREATE – INNOVATE
EU Grant identifier:	Τ2ΕDΚ-00468
Κάτοχος πνευματικών δικαιωμάτων:	© 2024 Elsevier Ltd. All rights reserved.
Ηλεκτρονική διεύθυνση στον εκδότη (link):	https://doi.org/10.1016/j.foodhyd.2024.109888
Εμφανίζεται στις συλλογές:	Ινστιτούτο Χημικής Βιολογίας - Επιστημονικό έργο