Measurement of β-glucan and other nutritional characteristics in distinct strains of <i>Agaricus subrufescens</i> mushrooms

Abstract

β-Glucan is a polysaccharide with anticancer properties, and it is present in the mushroom Agaricus subrufescens. The aim of this study was to compare two analytical methods to quantify β-glucan in mushrooms and analyze the nutritional characteristics, the concentration of phenolic compounds and the mineral composition, for A. subrufescens strains. An enzymatic extraction was performed, and β-glucan was quantified by spectrophotometry and high performance liquid chromatography (HPLC). No significant differences were found between the two methods of quantification of β-glucan. The CS7 and CS10 strains were found to have greater amounts of β-glucan, similar to the levels found in Pleurotus eryngii and Pleurotus-sajor-caju. Pleurotus ostreatus and Lentinula edodes samples contained even higher amounts of β-glucan. Significant differences were found in the nutritional characteristics for all parameters assessed, except for fat content. There was no difference between the strains with regard to phenolic compounds or certain mineral components. Fresh A. subrufescens mushrooms are not considered to be a high-protein food. However, they are a good source of fiber and minerals, in addition to being low in fat. Spectrophotometry presents the advantages of being quicker and lower in cost; this technique may be suggested as the standard for measurement of the β-glucan.

Keywords: β-Glucan, medicinal mushroom, royal sun mushroom, almond portobello.