Structural Elements of Lignin

Studies of a Lignin-Carbohydrate Complex. Pt. I. The Isolation of a Water Soluble Lignin-Carbohydrate Complex from Alkali Extraction ofEucalyptus obliqua

“…It was found (see below) that during acid hydrolysis a portion of lignin was also degraded simultaneously with the separation of carbohydrates. A number of workers (Adler 1961;Adler/ Lundquist 1963;Lundquist/Miksche 1965;Nimz 1967) reported the degradation of lignin into lower molecular weight compounds during acid hydrolysis. Thus it is suggested that the difference in methoxyl contents between insoluble alkali lignin and the hydrolysed product was due in part to the degradation of lignin molecule during acid hydrolysis of the lignincarbohydrate complex.…”

Roles of the Enantioselective Glutathione S -Transferases in Cleavage of β-Aryl Ether

“…These compounds were degraded to vanillate or syringate, and they were further degraded via the protocatechuate 4,5-cleavage pathway (8,13,16,17,19). In the process of lignin degradation, the cleavage of ␤-aryl ether is the indispensable step, because this intermolecular linkage is the most abundant in lignin (50 to 70%) (1). We have already isolated the ligDFEG gene cluster of S. paucimobilis SYK-6, which is involved in the degradation of ␤-aryl ether ( Fig.…”

Studies on a Lignin-Carbohydrate Complex. Pt. II. Characterisation of the Water-Soluble Lignin-Carbohydrate Complex

“…The infra-red spectroscopic examinations of the acetyl derivatives of the lignincarbohydrate complex and its hydrolysed product showed similar results. Adler (1961) demonstrated that the model compounds carrying oc-methyl and -guaiacyl ether groups were hydrolysed with acid at the α-position. The observed values of the acetoxy protons of the acetylated LCC and acetylated hydrolysed product (ΑΗΡ) are higher than the calculated values obtained from microanalysis, as shown in Table 5.…”