Preparative isolation of anthraquinones from the fungus Dermocybe sanguinea using enzymatic hydrolysis by the endogenous beta-glucosidase

A new and simple enzymatic method was developed for preparative isolation o f anthraquinone pigments from Dermocybe sanguinea. The endogenous beta-gluc osidase of the fungus was used to catalyze the hydrolysis of the O-glycosyl linkage in emodin- and dermocybin-1-beta-D-glucopyranosides. The developed enzymatic method was found to be effective for the pigment isolation, as t he hydrolysis occurred virtually completely, thus leading to a high pigment yield. Two fractions were obtained by the method: Fraction 1 (94% of the t otal pigment amount), containing almost exclusively the main pigments emodi n and dermocybin, and Fraction 2 (6%), containing the anthraquinone carboxy lic acids. A 10.5 kg amount of fresh fungi yielded 56 g of Fraction 1 and 3 .3 g of Fraction 2 anthraquinones. The anthraquinones in each fraction were separated by thin-layer chromatography using toluene-ethyl acetate-ethanol -formic acid (10:8:1:2, v/v/v/v) as eluent. The components on the chromatog rams were detected and characterized by measurements on a densitometer-spec trophotometer. Combined gas chromatography-mass spectrometry was applied to determine the anthraquinone derivatives of Fraction 1 after methylation an d acetylation.