Did you buy a Juicer or a blender? Juicer wouldn't really help, they basically extract the sugar waste and throw away the pulp which contains the bulk of the vitamins and minerals. The juices tend to be sweet (as packed with sugar) which feeds the bad bacteria...so basically the opposite of what you want to happen.
Blender is better. it keeps the nutrient rich pulp and can be more vegetable based so not as high in sugar, but the pulp can be quite fiberous, and encourages bowel movements in people with colons, so for us the effects can be quite strong.
I believe blending veg is good anti inflammatory for the bowel and would help keep pouchitis away, but you would get more bathroom visits due to teh fibre and not sure if it would help existing pouchitis.
personally im a blender and it has its uses..but has sideaffects too