Lignins preparation

The electrophoretic analyses of our various lignin samples has thus yielded results, which could not be obtained as yet by any other method. As in the case of proteins, electrophoresis supplies us with valuable information on the purity and homogeneity of the lignin preparations. The main limitation to a wider application of this method to lignin lies in the comparatively close mobility of all the samples thus far investigated (100). 

The next question is which criteria are suitable to indicate unequivocally similarities or distinctions betw een lignin preparations. In practice, physical, analytical and chemical degradative techniques are used to characterize lignins. 

Degradation of Polyaeric Lignin Preparations by Lignin Peroxidases... 

Solvolysis lignin prepared with 2,2-dimethoxypropane (24). c Wood meal singly labeled with 14C was employed. This estimation was made on the basis of radioactivity and UV absorbance (25). 

At this point, it must be emphasized that, based on previous structural analysis of isolated lignins (27), appropriate lignin model compounds and synthetic dehydrogenatively polymerized (DHP) lignin preparations (28-... 

Its nature as a lignin component is confirmed by its elemental composition and IR-spectrum compared with corresponding data for a milled wood lignin preparation, Table I and Figure 12. 

Figure 1. Ultraviolet-visible spectral concomitants of dissociation and oxidative cleavage of kraft lignin preparation during incubation at 0.047 gL 1 in aqueous 0.10 M NaOH between (1) 0 h and (5) 1340 h.

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