Enzymatic release and initial pH as responses to final pH. Total glucose (filled blue diamonds) and xylose (filled red squares) release as responses to final pH. Additionally, the initial pH is compared to the final pH by plotting initial pH of the acidic treatments (open green triangles) and the alkaline treatments (open red circles) as responses to the final pH. Black lines indicate fitted linear regression correlation curves (the regression coefficients, R2, exceeded 0.97 in both cases). Releases in g/kg original wheat straw dry matter.