Fig. 2

Effect of pretreatment on xylan yields from poplar variants. Five process conditions are shown. A sugar release from enzymatic hydrolysis for 120 h without prior pretreatment; B HTPH at 140 °C for 264.4 min (logR₀ = 3.6); C HTPH at 160 °C for 68.1 min (logR₀ = 3.6); D HTPH at 180 °C for 17.6 min (logR₀ = 3.6); and E HTPH at 180 °C for 44.1 min (logR₀ = 4.0). Co-hydrolysis for all HTPH conditions was performed for 24 h at an enzyme loading of 75 mg cellulase protein + 25 mg xylanase protein per gram glucan + xylan in raw biomass. Open circles represent rare variants, solid circles represent the low lignin comparator (GW-11012), solid squares represent the high lignin comparator (BESC-316), and the triangle and polygon represent BESC-97 and GW-9762 comparators, respectively. BESC standard is shown with a black star. The square inside the box plot represents the mean of the population. All samples except BESC standard were part of the descriptive box plot statistics