Simplified Colorimetric Determination of Glucosamine in the Tinder Conk Mushroom, Fomes fomentarius (Agaricomycetes)

Next to cellulose, chitin is the most abundant biopolymer on Earth and participates, in particular, in the assembly of the fungal cell walls. Easy monitoring of the amount of chitinous polymers could be advantageous during biotechnological cultivation and mushroom farming in order to control and optimize the production process. In this study, a modified colorimetric glucosamine (GlcN) assay was validated using high-performance anion exchange chromatography (HPAE) coupled with pulsed amperometric detection (PAD) following acid hydrolysis of the Fomes fomentarius cell walls. The average data obtained from both methods were well comparable. The HPAE-PAD analysis was suggested to be preferable because it had less data scattering, but it could be replaced with the simplified colorimetric GlcN screening in some cases such as low budgetary resources or an absence of suitable equipment, materials, or highly skilled staff. The robust, cost-effective colorimetric GlcN assay presented here can be readily requested, considering the rapidly growing market as well as the scientific and industrial potential of gourmet and medicinal mushrooms.