Complex sentence: The complexation probably occurs in the duodenum, because the acidic conditions in the stomach itself lead to protonation of the tomatine, and the protonated form of tomatine does not bind to cholesterol.
Split into simpler sentences: The complexation probably occurs in the duodenum, because the acidic conditions in the stomach leads to protonation of the tomatine. The protonated form of tomatine does not bind to cholesterol.