Page 285 - Advances in Textile Biotechnology

11

Enzymatic functionalization of cellulosic fi bres
for textile and other applications: xyloglucan
as a molecular anchor

H. BRUMER, Royal Institute of Technology (KTH), Sweden

Abstract: The inherent recalcitrance of paracrystalline cellulose, which
restricts the performance and applications of cellulosic biofi bres, has
been circumvented by a biomimetic approach that avoids the limitations
inherent in direct chemical methods for cellulose modifi cation. The
unique ability of the plant enzyme xyloglucan endo-transglycosylase
(XET) to produce chemo-enzymatically functionalized xyloglucan (XG)
polysaccharides was harnessed together with the inherently strong
interaction of XG with cellulose to surface-anchor the XG derivatives.
An overview of the use of XG-XET technology in the functionalization

of diverse cellulosic substrates is presented. Specific examples are given
to highlight the potential of the system for future applications in textiles,
pulp and paper, and biomedicine.
Key words: xyloglucan, xyloglucan endo-transglycosylase, cellulose,

surface modification, biocomposites, biomimetics, functionalization.

11.1 Introduction

Increasing demand on global resources for the production of materials has
long sustained interest in diverse applications of biofibres, ranging from

paper and packaging to construction materials and textiles. Although syn-

thetic, petrochemical-derived fibres sometimes have distinct performance
advantages over their natural counterparts, wood pulp, cotton, and bast
fibres are often desired, or even preferred, in many industrial and consumer

products. In some cases, this is trivially because of economic considerations;

(ligno)cellulosic biofibres are often cost-competitive with respect to syn-
thetic alternatives. On the other hand, biofibres possess unique material and

tactile properties that are often favoured by consumers, in addition to the
general perception that these plant-derived materials are both natural and
sustainable.

The physical/chemical surface modification of cellulosic fibres is very

often performed to improve functional properties for specifi c applications
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