초록
<P><B>Abstract</B></P> <P>The objective of this work was to study the suitability of the pretreated vine shoots as a source of lignin and to determine its structural features. The best conditions to achieve the aim of this work were 12% NaOH, 124°C and 105min, as they permitted a removal of 67.7% of the lignin present in the pretreated vine shoots and the obtaining of a solid with a 69.4% of glucan. This delignified solid was subjected to an enzymatic hydrolysis achieving a conversion of glucan to glucose close to 100%. The characterization of lignins extracted from pretreated vine shoots was carried out for the first time and the following techniques were employed: a quantitative acid hydrolysis, HPSEC, TGA, FTIR and Pyrolysis-GC/MS. With this proposal, products from the main fractions of the vine shoots (hemicellulosic oligosaccharides, lignin fragments and cellulosic substrates) could be obtained separately, being potentially suitable for further applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Alkali delignification of pretreated vine shoots allowed to remove a 67.7% of lignin. </LI> <LI> Lignins extracted under alkali conditions were characterized in depth. </LI> <LI> The S/G was similar in all the lignins and it ranged between 2.22 and 3.07. </LI> <LI> Enzymatic hydrolysis of delignified solid yielded a 100% of glucan to glucose. </LI> <LI> An integral biorefinery of the vine shoots can be achieved with the proposed approach. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>