Turmeric contains curcumin, a substance with powerful anti-inflammatory and antioxidant properties. Most studies use turmeric extracts that are standardized to include large amounts of curcumin. But the curcumin content of turmeric is just 3% by weight. Curcumin is poorly absorbed into the bloodstream. To improve this aspect, raw turmeric should be consumed with Black Pepper which contains piperine that enhances the curcumin absorption into the human blood stream. With piperine the absorption of curcumin by human blood stream improves by around 2000%.
You can find more information about benefits of Turmeric here.