Preparative Isolation of Anthraquinones from the Fungus Dermocybe sanguined Using Enzymatic Hydrolysis by the Endogenous β-Glucosidase

Abstract

Abstract A new and simple enzymatic method was developed for preparative isolation of anthraquinone pigments from Dermocybe sanguined. The endogenous β-glucosidase of the fungus was used to catalyze the hydrolysis of the O-glycosyl linkage in emodin- and dermocybin-1-β-ᴅ-glucopyranosides. The developed enzymatic method was found to be effective for the pigment isolation, as the hydrolysis occurred virtually completely, thus leading to a high pigment yield. Two fractions were obtained by the method: Fraction 1 (94% of the total pigment amount), containing almost exclusively the main pigments emodin and dermocybin, and Fraction 2 (6% ), containing the anthraquinone carboxylic 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 acetateethanol- formic acid (10:8:1:2, v/v/v/v) as eluent. The components on the chromatograms were detected and characterized by measurements on a densitometer-spectrophotometer. Combined gas chromatography-mass spectrometry was applied to determine the anthraquinone derivatives of Fraction 1 after methylation and acetylation.