Microbial and algal alginate gelation characterized by magnetic resonance
► Magnetic resonance techniques are used to quantify differences in the physical gelation of alginate from microbes and algae. ► Differences in water diffusion, T1, and T2 magnetic relaxation times are monitored as the gel forms and ages. ► O-Deacetylated alginate from Pseudomonas aeruginosa FRD1153...
Gespeichert in:
Veröffentlicht in: | Journal of biotechnology 2012-10, Vol.161 (3), p.320-327 |
---|---|
Hauptverfasser: | , , , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | ► Magnetic resonance techniques are used to quantify differences in the physical gelation of alginate from microbes and algae. ► Differences in water diffusion, T1, and T2 magnetic relaxation times are monitored as the gel forms and ages. ► O-Deacetylated alginate from Pseudomonas aeruginosa FRD1153 forms the most rigid and heterogeneous gel. ► Bacterial alginates form a more rigid and heterogeneous gel than algal alginate. ► Bacterial alginates contract and expel water more than algal alginate indicating larger molecular stress during gelation.
Advanced magnetic resonance (MR) relaxation and diffusion correlation measurements and imaging provide a means to non-invasively monitor gelation for biotechnology applications. In this study, MR is used to characterize physical gelation of three alginates with distinct chemical structures; an algal alginate, which is not O-acetylated but contains poly guluronate (G) blocks, bacterial alginate from Pseudomonas aeruginosa, which does not have poly-G blocks, but is O-acetylated at the C2 and/or C3 of the mannuronate residues, and alginate from a P. aeruginosa mutant that lacks O-acetyl groups. The MR data indicate that diffusion-reaction front gelation with Ca2+ ions generates gels of different bulk homogeneities dependent on the alginate structure. Shorter spin–spin T2 magnetic relaxation times in the alginate gels that lack O-acetyl groups indicate stronger molecular interaction between the water and biopolymer. The data characterize gel differences over a hierarchy of scales from molecular to system size. |
---|---|
ISSN: | 0168-1656 1873-4863 |
DOI: | 10.1016/j.jbiotec.2012.04.016 |