  We derive the first quantum gravitational corrections to the inflationary
power spectra for a general single-field scalar-tensor theory which includes a
non-minimal coupling to gravity, a non-standard scalar kinetic term and an
arbitrary potential of the scalar field. We obtain these corrections from a
semiclassical expansion of the Wheeler-DeWitt equation, which, in turn, governs
the full quantum dynamics in the canonical approach to quantum gravity. We
discuss the magnitude and relevance of these corrections, as well as their
characteristic signature in the inflationary spectral observables. We compare
our results to similar calculations performed for a minimally coupled scalar
field with a canonical kinetic term and discuss the impact of the non-minimal
coupling on the quantum gravitational corrections.
