Chemical characterization of four wild edible mycorrhizal mushrooms: the same geographical origin, but a great biodiversity

The present work reports the chemical characterization of four wild edible mycorrhizal mushrooms fi-om two different genus: Leccinum molle (Bon) Bon, Leccinum vulpinum Watling, Suillus granulatus (L.) Roussel and Suillus luteus (L. : Fries) Gray. This characterization was an attempt to find some compounds of interest, namely reducing sugars, unsaturated fatty acids, vitamin E and phenolic compounds, the two latter, known for their antioxidant capacity as scavengers of free radicais. The antioxidant potential of the species was also evaluated. Both Leccinum species and the S. granulatus revealed the presence of the reducing sugar fructose. However, mannitol and trehalose were the main free sugars quantified in the studied samples. Unsaturated fatty acids were the predominant fatty acids class, and R- and ytocopherol were the main isoforms of vitamin E found in the studied species. More differences between the species were observed in the phenolic acids profiles. These compounds are known as sccondary meíabolites associated wiíh stressful conditions. Therefore, since mushrooms are strongly influenced by the surrounding envíronment, it is natural that such differences occur, even among species of the same genus. Ali the species revealed antioxidant properties, being the lower £ 50 values observed for the P-carotene bleaching inhibition. Overall, the studied edible mycorrhizal species can be directly included in the diet in order to take advantage of the present bioactive compounds (i. e. vitamins, unsaturated fatty acids, reducing and/or other biologically active sugars). In addition to taking advantage of these products of the primary metabolism, it is also possible to take advantage of secondary metabolites which also possess, among others, antioxidant properties.