Fig. 3

Lignin, glucuronoarabinoxylan (GAX), and glucan (cellulose) removal after 7 weeks of fungal growth. Cs Ceriporiopsis subvermispora, Pe Pleurotus eryngii, Le Lentinula edodes. Compositional analysis by using quantitative ¹³C-IS py-GC–MS (lignin) and constituent monosaccharide analysis after H₂SO₄ hydrolysis (carbohydrates). Average and standard deviation of analytical triplicates on pooled biological triplicates. It is important to take some limitations of the methods used for carbohydrate quantification into consideration. First, the hydrolysis of polysaccharides to constituent monosaccharides does not allow cellulose and fungal β-glucan to be distinguished. Cellulose determination was, however, not expected to be largely affected, since fungal biomass was present in minor amounts only, as estimated from ergosterol content [13]. Second, fungal-treated cellulose and glucuronoarabinoxylan (GAX) were expected to be more completely acid-hydrolyzed than untreated material, thereby resulting in underestimation of the amount of degraded carbohydrates