Free radical studies of lignin, lignin degradation products and soil humic acids

Details Free radical studies of lignin, lignin degradation products and soil humic acids Free radical studies of lignin, lignin degradation products and soil humic acids

Oct 1964

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1964gecoa..28.1615s&link_type=abstract

Geochimica et Cosmochimica Acta, vol. 28, Issue 10-11, pp.1615-1622

Mathematics

Logic

1

Scientific paper

Native lignin, various lignin preparations and a variety of humic acids isolated from soil and lignite have been shown to contain stable organic free radicals by means of electron paramagnetic resonance spectrometry. The radical species are not contaminants, but an integral part of the natural polymers. Chemical and EPR spectral evidence suggests that the radical species is an ortho- or para-semiquinone, which is coexistent with quinhydrone and quinone moieties. Although the nature of the stable free radical appears to be the same in lignins and humic acids, the concentration of these species varies considerably. Thus, the unpaired electron spin concentration increases from low values in native lignin to intermediate values in lignin preparations and finally to relatively high values in soil humic acids and leonardite. These results are significant because 1. (1) they lend experimental support to present theories regarding the free radical mechanism of the biological degradation of lignin; 2. (2) they illustrate a technique (EPR spectrometry) which may provide valuable information on the structures of humic acids; and 3. (3) they provide a basis for future studies of subtle structural changes in lignin and humic acids.

Affiliated with

Also associated with

No associations

Rating

Free radical studies of lignin, lignin degradation products and soil humic acids does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Free radical studies of lignin, lignin degradation products and soil humic acids, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Free radical studies of lignin, lignin degradation products and soil humic acids will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1609858