Purpose: To identify the structures of cellulose-extract derivative (CED) formed by heating
Lentinus edodes
cellulose in water surroundings that can efficiently inhibit aflatoxin production by
Aspergillus flavus
.
Methods: CED was purified on Sepharose CL-6B columns, and then structurally characterized using
amino acid analyzer, gas chromatography, Fourier transform infrared spectroscopy, and polyacrylamide
gel electrophoresis.
Results: CED completely inhibited aflatoxin AFB1 production by
A. flavus at concentrations ≥ 100 μg/
mL. Chemical analysis indicated that CED contained 82 % carbohydrate and 18 % protein and has a
molecular weight of approximately 24 kDa. Monosaccharide component analysis indicates that glucose
was the predominant monosaccharide of CED. Analysis by Smith degradation and enzymatic hydrolysis
indicate that there were only (1, 4)-glycosidic linkages in the CED polysaccharide chains. The protein
backbone of CED contained 15 kinds of amino acid with higher levels of glutamic acid, aspartic acid,
leucine and alanine.
Conclusion: CED was identified as a complex of peptide and polysaccharide structures possessing β-
(1, 4)-glucan backbones, and it provides a theoretical basis for developing polysaccharide preparations
to control aflatoxin contamination with medical and food science applications.
