Heterogeneously deacetylated chitosans possess an unexpected regular pattern favoring acetylation at every third position
Résumé
Chitosans are promising biopolymers for diverse applications, with material properties and bioactivities depending i.a . on their pattern of acetylation (PA). Commercial chitosans are typically produced by heterogeneous deacetylation of chitin, but whether this process yields chitosans with a random or block-wise PA has been debated for decades. Using a combination of recently developed in vitro assays and in silico modeling surprisingly revealed that both hypotheses are wrong; instead, we found a more regular PA in heterogeneously deacetylated chitosans, with acetylated units overrepresented at every third position in the polymer chain. Compared to random-PA chitosans produced by homogeneous deacetylation of chitin or chemical N -acetylation of polyglucosamine, this regular PA increases the elicitation activity in plants, and generates different product profiles and distributions after enzymatic and chemical cleavage. A regular PA may be beneficial for some applications but detrimental for others, stressing the relevance of the production process for product development.
Domaines
PolymèresOrigine | Fichiers éditeurs autorisés sur une archive ouverte |
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