Bio-Based Hydrogels Composed of Humic Matter and Pectins of Different Degree of Methyl-Esterification

Molecules

Davide Savy¹  Assunta Nuzzo¹  Alessandro Piccolo¹  VincenzoDi Meo²  Pierluigi Mazzei³ 

[1] Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l’Ambiente, l’Agroalimentare ed i Nuovi Materiali (CERMANU), Università di Napoli Federico II, Via Università 100, 80055 Portici (NA), Italy;Dipartimento di Agraria, Università di Napoli Federico II, Via Università 100, 80055 Portici (NA), Italy;Dipartimento di Farmacia (DIFARMA), Università di Salerno, Via Giovanni Paolo II 132, 84084 Fisciano (SA), Italy;

关键词: hydrogels;    humic substances;    compost;    release;    low and high degree of pectin methylation;    NMR;   

DOI  :  10.3390/molecules25122936

来源: DOAJ

【 摘 要 】

We prepared humo-pectic hydrogels through ionotropic gelation by crosslinking natural pectins of different degree of methyl-esterification with either humic substances (HS) extracted from cow manure compost or humic-like substances (HULIS) from depolymerized lignocellulose biorefinery waste. The hydrogels were characterized by solid-state ¹³C-NMR spectroscopy, scanning electron microscopy, spectroscopic magnetic resonance imaging and rheological analyses. Their ability to work as controlled release systems was tested by following the release kinetics of a previously incorporated model phenolic compound, like phloroglucinol. Our results indicated that the release properties of hydrogels were influenced by the molecular composition of HS and HULIS and by the different degrees of methyl-esterification of pectins. The hydrogel made by the high methoxyl pectin and HS showed the fastest rate of phloroglucinol release, and this was attributed not only to its morphological structure and crosslinking density but also to the least formation of ionic interactions between phloroglucinol and the polysaccharidic chains. Our study suggests that the efficiency of novel humo-pectic hydrogels as sustainable carriers of agroproducts to crops is related to a careful choice of the characteristics of their components.

【 授权许可】

Unknown