HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Linhares, L. F. Articles by Martin, J. P. Search for Related Content PubMed Articles by Linhares, L. F. Articles by Martin, J. P. Agricola Articles by Linhares, L. F. Articles by Martin, J. P.

Carbohydrate Content of Fungal Humic Acid-type Polymers (Melanins)¹

ABSTRACT

The carbohydrate contents of a variety of fungal humic acid-type melanins ranged from 1.1 to 5.9%. Values were 1.7 to 2.6% for soil humic acids and 0.4% for Leonardite peat humic acid. Fungal culture medium polymers not precipitated by acid and fungal cells contained from 12 to 55% carbohydrates. The uronic acid content of all products was very low, ranging from essentially zero (not detected) to 1.1%. Stachybotrys atra was the only fungus where uronic acids were detected in all samples. Uronic acids were, however, present in all soils, the values ranging from 0.3 to 0.4%. Recovery of uronic acids after acid hydrolysis using galacturonic acid as a check gave low values. The necessity of eliminating interferring substances before the colorimetric determination of sugars and uronic acids in soil and fungal polysaccharide hydrolysates was demonstrated. Thin-layer chromatography of concentrated hydrolysates from the humic acid-type fungal melanins and soil humic acids showed the presence of glucose, galactose, mannose, and xylose in most of the samples. A mass spectrum of the pyrolysis fragments of Aspergillus glaucus sp. humic acid-type polymer showed definite series peaks related to polysaccharides, the most prominent, however, were related to proteins and phenolic substances.

¹ Contribution from Dept. of Soil and Environmental Sciences, Univ. of California, Riverside 92521 and Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Brazil.

² Visiting Professor of Microbiology from Univ. of Rio de Janeiro, Brazil, and Professor of Soil Science, Univ. of California, Riverside, respectively. The authors thank J. O. Ervin for technical laboratory assistance.

Received for publication July 28, 1978. Accepted for publication November 14, 1978.

This article has been cited by other articles:

				R. Hartenstein Sludge Decomposition and Stabilization Science, May 15, 1981; 212(4496): 743 - 749. [Abstract] [PDF]