Lead acetate Lignin

The breakdown of furan aldehydes leads to the formation of formic and levulinic acid. Moreover, acetic acid is formed during the degradation of hemicellulose. Partial breakdown of lignin can generate a variety of phenolic compounds (23), which also inhibit S. cerevisiae (14,15). In contrast to furan aldehydes and aliphatic acids, the toxic effect of specific phenolic compounds is highly variable (15). Different raw materials and different approaches to prepare lignocellulose hydrolysates will result in different concentrations of the fermentation inhibitors (16,17). 

The pathways of carbon flow in eukaryotes are more complex than in prokaryotes, mainly because the C2 units produced within mitochondria can be exported (e.g. for lipid biosynthesis) only as part of a citrate unit produced in the citric acid cycle. The branch point in carbon flow to either isoprene or acetate can lead to additional isotopic fractionation. In general, it seems that n-alkyl hpids in a particular organism are depleted in 13C by c. 1.5%o relative to isoprenoids produced from the same substrate (Hayes 1993). In higher plants, the phenolic precursors of lignin derive from glucose (Fig. 2.29), so it is not surprising that the carbon isotopic composition of lignin reflects the major photosynthetic pathway involved (C3 or C4 Benner et al. 1987). 

Misc with water, methanol, ethanol, acetone, acetic acid, dioxane, ethylene glyco], U.S.P. glycerol, phenol, Very slightly sol in ether, benzene. Dissolves casein, glucose, zein, tannins, starch, lignin, polyvinyl alcohol, cellulose acetate, nylon, the chlorides nf copper, lead, zinc, tin, cobalt, iron, aluminum, nickd, the acetates of the alkali metals, some inorganic sulfates and nitrates. LDg, i.p. in mice, rats 4.6, 5.7 g/kg, Pham-Huu-Chanh tt al, Toxicol. Appt Pharmacol 26, 596 (1973). 

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