Fig. 2

Comparison of the change in recalcitrance during enzymatic hydrolysis. a Each re-hydrolysis round consisted of hydrolysis with 7.5 FPU cellulase at 50 °C for 1 h followed by three washing rounds with distilled water. The hydrolysis of P. densiflora was complete at the end of 6th round, and the hydrolysis of Q. acutissima was complete at the end of the 9th round. Filter paper and Avicel released reducing sugars at the end of the 14th round. b The enzymatic degradation of wood fibers and ray parenchyma cells from Q. acutissima and tracheids (early and late tracheids) from P. densiflora are compared