Is it possible to use puree in a siphon whip?

Yes you can; you can do both sweet and savory foams.

I never did it (I don't have a siphon), but from what I can feel when eating foam/espuma is that the input purée needs to be quite fine; blend/purée and then pass through a fine mesh sieve.

Just google "foam espuma recipe" and you will find a lot of recipes.