In our experiment, we used an enzyme-based test kit by Megazyme© Ltd. (Bray, Wicklow County, Ireland). The previously described method is expected to deliver reliable results for beta-glucan content determination (Bak et al., 2014 and Chatterjee et al., 2013).
Very recently, McCleary and Draga (2016)published very valuable data about beta-glucans in different mushroom species. Different alternative methods (e.g. GEM assay) are compared to the Megazyme© assay kit with different optimization steps. The study shows that the Megazyme© method seems to be the most reliable method due to a hydrolysis step (with HCl or H2SO4) combined with enzymatic incubation (McCleary & Draga, 2016). This work also showed that sulfuric acid instead of hydrochloric acid can be used for dissolving mushroom probes for optimal measurement of total glucan content. HCl and H2SO4 behave similarly, but for some species (Gandoderma lucidum and Poria cocos – not investigated in this study) H2SO4 seems to result in higher beta-glucan values due to a better dissolving of the mushroom samples.