There is not. However, some of the levels might have some special effects, to make them looking more visually appealing. Anyway, I never had a problem Knytt Stories looking pixelated. Moreover, it is intended, most of the levels are pixelart based. For example the Knytt Stories Plus mod does support integer scaling (2x) to actually prevent the game looking blurry on fullscreen...
EDIT: Like egomassive said, this way the game is much better than any aliasing. Additionally, there is also a separate utility "Scaler" for the original Knytt Stories and other MMF games and that does the same thing.