Fig. 8

Molar conversion yields of HMF and levulinic acid from insoluble material untreated, swollen in TFA, and gelatinized in TFA for wild-type (WT) and transgenic poplar lines with and without catalytic delignification (CDL). a Milled poplar particles. b CDL-treated poplar particles. c Milled particles swollen in TFA at –20°C for 15 h. d CDL-treated particles swollen in TFA at –20°C for 15 h. e Milled particles swollen in TFA at –20°C for 15 h, then heated to 55°C for 4 h. f CDL-treatment particles swollen in TFA at –20°C for 15 h, then heated to 55°C for 4 h. WT = (Populus tremula × P. alba cv. INRA 717-1B4), high S-lignin = pAtC4H:AtF5H1, high G-lignin = pAtC4H:PtF5H2 RNAi, and high OH-G-lignin = p35S:PtCOMTa RNAi. Monolignol distributions are provided in Table 1. Control particles and never-dried TFA-treated materials (50 or 75 mg) were suspended in 2 ml of 100 mM each of maleic acid and AlCl₃ and reacted at 180 °C for 15 minutes. Values are the means ± S.D. of three determinations.