ISOLATION, PURIFICATION AND CHEMICAL CHARACTERIZATION OF ALKALI-EXTRACTABLE POLYSACCHARIDES FROM THE CELL WALLS OF TALAROMYCES SPECIES

摘要

From the alkali-extractable material from cell walls of some species of Talaromyces a water-extractable (F1S) and a water-unextractable F1I) fraction were obtained. Fraction F1S (representing 2.5-12.5% of the cell wall) was filtered through Sepharose CL-6B in order to purify polysaccharides that were individually studied for chemical composition and structure. According to the structure of these polysaccharides, the species investigated could be grouped as follows: T. stipitatus, T. bacillisporus and T. macrosporus had as their main component a heteropolysaccharide containing beta-(1-->2) and beta-(1-->5) galactofuranosyl residues; in T. wortmannii and T. rotundus the most abundant component was a polysaccharide with beta-(1-->2) and beta-(1-->3)-linked galactofuranose; T. luteus contained in fraction F1S a single polysaccharide, identified as a highly branched galacto-gluco-mannan. Fraction F1I was identified as an a-glucan in most of the species. These results reflect the complexity of the genus and could have chemotaxonomic value.