cerevisiae to successfully ferment pentose
and hexose sugars.
The contribution of microbial-derived saccharides to the carbohydrate composition of soil can he estimated using quotients of sugar monomers because microorganisms synthesise little if any pentoses, while the pentoses xylose and arabinose are ubiquitous constituents of plant cells (Oades 1984).
With increasing soil depth, the ratios of hexoses to pentoses as well as the concentrations of neutral sugars and uronic acids did not show a clear trend (Fig.
The Bw3 horizon showed a minimum of non-cellulosic carbohydrates with low ratios of hexoses to pentoses.
However, the ratios of hexoses to pentoses in bulk soil samples and alkaline extracts showed similar trends with increasing soil depth.
Thus, kidney transplantation lowers pentosidine concentrations to nearly normal ; this suggests that some pentosidine precursor, perhaps a pentose
or dicarbonyl sugar, is not efficiently excreted and accumulates in serum.
Recognizing the large amount of sugars in corn cobs and other agricultural residues, Dunning and Lathrop hydrolyzed hemicellulose with mild sulfuric acid treatments, forming a solution of mostly pentoses.
After successfully finding ways to break down corn fiber into hexoses and pentoses, the researchers' next challenge is to identify or develop strains of microorganisms that will convert both of these sugar types to ethanol as efficiently as bakers' yeast makes it commercially from hexoses.
The ratio of C in the 93-60 ppm region to that in the 113-93 ppm region was between 4 and 5 in most fractions, indicating a mixture of pentoses and hexoses.
This occurred because, whereas the model assumed that the carbohydrate component was 100% hexose, there were always pentoses present.
In this study, the ratio was [is less than] 5 in all fractions (except those treated with HF), suggesting the presence of pentoses and hexoses but no melanoidins.