Da die verholzte Zellwand ein sehr komplexes Gebilde darstellt, wurde untersucht, ob ihre blaue Primarfluoreszenz als spezifische Nachweisreaktion fur Verholzung uberhaupt gelten kann.

Fluoreszenzmikroskopische Untersuchungen an verholzten Zellwänden

Chapter viii – the elementary composition and constituent groups of lignin

The various ways in which lignin may be isolated are briefly described with special emphasis on those methods which allow of a separation under mild conditions. Although the problem of the isolation of the bulk of lignin in a chemically unaltered state is not completely solved as yet, encouraging results have recently been obtained by grinding wood powder in a non-swelling solvent and extracting the lignin with dioxan („Bjorkman-lignin”). The analytical composition of this product is given. The question of the structure of lignin is treated in thelight of our present knowledge and is based on the results of numerous investigations. Only those having immediate connection with the structural problems could be taken into account. The work has been divided into two parts: one dealing with the determination of the substituents on the aromatic nuclei (following oxidative and reductive degradations), the other giving information on the structural features of the three carbon atoms in the side chains. In connection with the latter, the most important lignin reactions are briefly discussed as those reactions take place in the non-aromatic portion of lignin. The probable-pathway of lignin biosynthesis is outlined. The first part describes the stages which result in the transformation of carbohydrates into molecules having a phenyl-propane skeleton (C6−C3.) The second part deals with the laboratory transformation of the latter into an artificial lignin by enzymatic oxidation reactions and polymerization reactions.

Über die Isolierung, Struktur und Biosynthese des Lignins

Chapter xiv – the hydrolysis of lignin

Nach Kratzl unterscheiden wir die durch Farbstoffe zustandekommenden Holzfarbungen und die Holzfarbreaktionen, bei denen ungefarbte Agentien das Lignin chemisch verandern. Bei den Holzfarbreaktionen sind es entweder Oxydationsvorgange (Maule, Jayme) oder Reaktionen mit z. B. Phenolen (Wiesnersche Phloroglucin-Salzsaurereaktion) und Aminen.

Vergleichende Versuche über Verholzungsreaktionen und Fluoreszenz

http://link.springer.com/content/pdf/10.1007/BF00898853.pdf

F. Rettenbacher

Papers

ber das Bauprinzip der Seitenketten der Ligninsulfosuren: IV. Mitteilung zum Nachweis einer Coniferylaldehydstruktur