Inhibitory effects of compounds with guaiacyl and syringyl structure, representing the structure of native lignin, were studied on model cultures of bacteria, yeasts, yeast-like microorganisms and moulds. Isoeugenol exhibited the most pronounced inhibitory effect on growth of the studied microorganisms.

Glucuronoyl esterase is a novel carbohydrate esterase recently discovered in the cellulolytic system of the wood-rotting fungus Schizophyllum commune on the basis of its ability to hydrolyze methyl ester of 4-O-methyl-D-glucuronic acid. This substrate was not fully corresponding to the anticipated function of the enzyme to hydrolyze esters between xylan-bound 4-O-methyl-D-glucuronic acid and lignin alcohols occurring in plant cell walls. In this work we showed that the enzyme was capable of hydrolyzing two synthetic compounds that mimic the ester linkages described in lignin-carbohydrate complexes, esters of 4-O-methyl-D-glucuronic and D-glucuronic acid with 3-(4-methoxyphenyl)propyl alcohol. A comparison of kinetics of hydrolysis of methyl and 3-(4-methoxyphenyl)propyl esters indicated that the glucuronoyl esterase recognizes the uronic acid part of the substrates better than the alcohol type. The catalytic efficiency of the enzyme was much higher with the ester of 4-O-methyl-D-glucuronic acid than with that of D-glucuronic acid. Examination of the action of glucuronoyl esterase on a series of methyl esters of 4-O-methyl-D-glucopyranuronosyl residues alpha-1,2-linked to xylose and several xylooligosaccharides suggested that the rate of deesterification is independent of the character of the carbohydrate part glycosylated by the 4-O-methyl-D-glucuronic acid.

The antimicrobial action of 11 compounds involving guaiacyl- and syringyl-like structures (low-molecular-weight part of lignin), gallic acid and its derivatives, cinnamic acid and its derivatives, veratric acid, anisic acid and crotonic acid (a total of 25 compounds) against bacteria, yeast-like organisms and protozoa was examined. Aromatic compounds modified in the C-side chain and aldehydes were effective preferentially against Trichomonas vaginalis, whereas against bacteria and yeast-like organisms eugenol was the most effective inhibitor.

Der Zerfallsmechanismus einiger monomerer Lignin‐Bauelemente (1–13) mit verschiedener Struktur der Seitenkette wird beschrieben.

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3-(4-Methoxyphenyl)propyl D-glucuronate, 3-(4-methoxyphenyl)propyl methyl 4-O-methyl-α-Dglucopyranosiduronate, 3-(4-methoxyphenyl)propyl 1,2,3,4-tetra-O-acetyl-α-D-glucopyranuronate and 3-(4-methoxyphenyl)propyl 1,2-(S):3,5-di-O-benzylidene-α-D-glucofuranuronate were prepared as a model substances for the ester lignin-saccharide bonds. Rates of acid-catalyzed hydrolysis of the prepared compounds in 1 M HCl in acetonitrile-water 3 : 1 at 20 °C have been measured by LC-DAD analysis and it showed the low stability of the ester bonds towards acid hydrolysis.

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O-Glycosidation of 3-(4-methoxyphenyl) propyl alcohol, benzyl alcohol and vanillin with totally unprotected D-glucose, performed in a heterogeneous media and promoted by anhydrous ferric chloride, afforded competent D-glucofuranosides as the major and D-glucopyranosides as the minor products of the reaction.