Characterization of the transformations of lignocellulosic structures upon degradation in planted soil

Biorenewable thermosetting copolymer based on soybean oil and eugenol

“…High-performance bismaleimide resin has also been synthesized utilizing eugenol and succinic acid [39]. On the other hand, even though nowadays eugenol is extracted from clove, studies have shown that eugenol can potentially be obtained from pyrolysis [40,41] or depolymerization [42] of lignin. Because of the low cost and abundance of lignin, the price of eugenol can be dramatically decreased if an economical pathway of obtaining eugenol from lignin is developed.…”

Upgrading of Lignin-Derived Compounds: Reactions of Eugenol Catalyzed by HY Zeolite and by Pt/γ-Al2O3

“…For example, Telysheva et al [8] obtained phenol, guaiacol (2-methoxyphenol), substituted guaiacols, 4-allyl-2-methoxyphenol (eugenol), 4-hydroxy-3-methoxybenzaldehyde (vanillin), and substituted vanillin from pyrolytic Kraft lignin. These compounds can be converted catalytically into useful fuel components and chemicals, as shown in several recent investigations [9][10][11][12][13][14][15][16][17][18][19].…”

Formation Mechanisms of Humic Substances in the Environment

“…Most of these browning reactions involve carbonyl -amine reactions that result in the formation of highly colored high -and low -molecular -weight polymers (Hidalgo and Zamora, 2000 ). Quinones are produced during the decomposition of lignin and by the oxidation of polyphenols; they are highly unstable and very reactive in aqueous media (Stevenson, 1994 ;Filley et al, 2002 ;Telysheva et al, 2007 ). They readily combine with amine, sulfydryl, phenol, indole and imidazole groups of amino acids, peptides, and proteins to give even more intensely colored products than simple quinones or phenol polymers (Bittner, 2006 ).…”

“…The phenols could then be utilized as substrates by microbes to form ketoacids via deoxygenases; however, it has been shown that less than 1% lignin carbon is incorporated into new biomass . The phenols can also become substrates for synthetic humifi cation reactions Yavmetidinov et al, 2003 ;Telysheva et al, 2007 ). Polyphenols are the most reactive biomolecules in participating in polymerization and polycondensation humifi cation reactions, especially in the presence of enzymes such as laccase and abiotic catalysts, such as Fe and Mn oxides .…”

“…Polyphenols are the most reactive biomolecules in participating in polymerization and polycondensation humifi cation reactions, especially in the presence of enzymes such as laccase and abiotic catalysts, such as Fe and Mn oxides . Telysheva et al (2007) studied the degradation of lignin in planted soils using a range of chemical and spectroscopic analytical techniques. They found that initially the carbohydrate component of the lignin was preferentially degraded, followed by the oxidative decomposition of the lignin moieties which involved removal of side chains (demethylation and demethoxylation).…”