title: Cellulose-pectin composite hydrogels: Intermolecular interactions and material properties depend on order of assembly.
abstract: Plant cell walls have a unique combination of strength and flexibility however, further investigations are required to understand how those properties arise from the assembly of the relevant biopolymers. Recent studies indicate that Ca2+-pectates can act as load-bearing components in cell walls. To investigate this proposed role of pectins, bioinspired wall models were synthesised based on bacterial cellulose containing pectin-calcium gels by varying the order of assembly of cellulose/pectin networks, pectin degree of methylesterification and calcium concentration. Hydrogels in which pectin-calcium assembly occurred prior to cellulose synthesis showed evidence for direct cellulose/pectin interactions from small-angle scattering (SAXS and SANS), had the densest networks and the lowest normal stress. The strength of the pectin-calcium gel affected cellulose structure, crystallinity and material properties. The results highlight the importance of the order of assembly on the properties of cellulose composite networks and support the role of pectin in the mechanics of cell walls.
authors.affiliation: ARC Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, 4072, Australia. Electronic address: patricia2011.ls@gmail.com.
authors.forename: Patricia
authors.initials: P
authors.lastname: Lopez-Sanchez
authors.affiliation: ARC Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, 4072, Australia; Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, New South Wales, 2232, Australia.
authors.forename: Marta
authors.initials: M
authors.lastname: Martinez-Sanz
authors.affiliation: School of Chemical Engineering, The University of Queensland, Brisbane, 4072, Australia.
authors.forename: Mauricio R
authors.initials: MR
authors.lastname: Bonilla
authors.affiliation: ARC Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, 4072, Australia.
authors.forename: Dongjie
authors.initials: D
authors.lastname: Wang
authors.affiliation: Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, New South Wales, 2232, Australia.
authors.forename: Elliot P
authors.initials: EP
authors.lastname: Gilbert
authors.affiliation: School of Chemical Engineering, The University of Queensland, Brisbane, 4072, Australia.
authors.forename: Jason R
authors.initials: JR
authors.lastname: Stokes
authors.affiliation: ARC Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, 4072, Australia.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Gidley
mesh_terms: D002473:Cell Wall; D002482:Cellulose / Q000737:chemistry*; D020100:Hydrogels / Q000138:chemical synthesis / Q000737:chemistry*; D010368:Pectins / Q000737:chemistry*; D053838:Scattering, Small Angle; D014961:X-Ray Diffraction
chemical_list: D020100:Hydrogels; D010368:Pectins; D002482:Cellulose
keywords: Cellulose; Mechanics; Pectin; SANS; SAXS; XRD