Arabinogalactan is a constituent of a flowering plant. It is basically a proteoglycans, a combination of protein and sugar found in the cells. Arabinogalactan is found in a number of vegetable and fruits and it makes the immune systems strong. It helps in building healthy bacteria is our bodies. The fiber of arabinogalactan can be used as stabilizer, and also to lower down cholesterol levels and treat various infections. The side effects are rare and include bloating and flatulence.