pH-dependent complexation of lysozyme with low methoxyl (LM) pectin

Abstract : In order to understand the effect of pH on the formation of electrostatic complexes between lysozyme and low methoxyl (LM) pectin, mixtures were prepared at a fixed lysozyme concentration (0.714g.L−1) by progressive addition of LM pectin (from 0 to 4g.L−1). Turbidity analysis allowed to determine specific conditions of pH and lysozyme/LM pectin ratio for optimal complex aggregation. The intrinsic fluorescence enhancement observed upon binding of LM pectin to lysozyme was correlated with the formation of intermolecular aggregates. Conversely, the intrinsic fluorescence decrease observed at higher LM pectin amounts was correlated with the dissociation of intermolecular aggregates. UV absorption spectroscopy showed modifications in lysozyme conformation during both the aggregation phase and the dissociation phase. The role of electrostatic interactions in the formation of lysozyme/LM pectin complexes is discussed in relation to the overall structure and the charge density profile of the two biopolymers.
Document type :
Journal articles
Complete list of metadatas

https://hal-univ-lyon1.archives-ouvertes.fr/hal-02187817
Contributor : Laure-Hélène Davoine <>
Submitted on : Thursday, July 18, 2019 - 10:30:23 AM
Last modification on : Thursday, July 25, 2019 - 4:42:05 PM

Identifiers

Collections

Citation

Nadia Oulahal, Adem Gharsallaoui, Chedia Ben Amara, Pascal Degraeve. pH-dependent complexation of lysozyme with low methoxyl (LM) pectin. Food Chemistry, Elsevier, 2017, Special Issue: 9th International Conference on Water in Food, 236, pp.127-133. ⟨10.1016/j.foodchem.2017.03.124⟩. ⟨hal-02187817⟩

Share

Metrics

Record views

6