It needn't be just a process to produce carbohydrates and sugars-
Granted that there may be room for all sorts of other frameworks, but carbon provides a pretty good basis for life. It's one of the most promiscuous of the lighter elements and can form all sorts of complex molecules. Even with very different life-forms, it's possible to imagine that a lot of the basic chemistry might be the same.
Seems I've seen either a Website or documentary lately that postulated animals that used sunlight to produce food. They looked like big mushrooms, but were mobile and competed for sun-lit real estate. Does that ring a bell?
Yeah, it was a documentary (I think on National Geographic) that postulated some possible life forms around other types of star systems. The animation was kind of cheesy. I enjoyed it a bit, but was a bit put-off that they only seemed to have 2-3 life-forms per planet. I'm guessing that just about any biosphere capable of generating large creatures is going to be quite rich in species.