Figure 4

Effect of extractives from forbs on enzymatic deconstruction of CS. Water and solvent-soluble materials were extracted from the indicated forbs or from CS. The total heights of the bars indicate the total Glc measured in each sample following enzymatic digestion of each CS sample by C/HTec2, added at 10 mg/g glucan for 48 hours at 50°C. The different shadings indicate the amount of Glc originating from free Glc that was present in the extractives added to each reaction (light bars), the Glc released by the enzymes due to the enzymatic digestion of the CS biomass (black bars), and the Glc released upon digestion of soluble biomass components that were present in the extractives added to the reactions (medium grey bars). Reduction of polymeric Glc yields from the CS (black bars) compared to the no-extractives control (38.2% Glc yield) indicates the degree of enzyme inhibition by the extractives from each plant species. The differences in digestibility of GR, QA, and CS were significantly different from the CS alone at P < 0.05. AHP, alkaline hydrogen peroxide; CS, corn stover; Glc, total glucose; GR, goldenrod; LQ, lamb’s quarters; MW, milkweed; QA, Queen Anne’s lace.