From the Manufacturer’s Label:
Support for Healthy Aging
pTeroPure® Pterostilbene is 99% pure pterostilbene, a compound that occurs naturally in small amounts in fruits such as blueberries, huckleberries and grapes. Pterostilbene is similar in structure to the healthy compound resveratrol.
Manufactured by Source Naturals
Contains No: Yeast, dairy, egg, gluten, soy, wheat, sugar, starch, salt, preservatives or artificial color, flavor or fragrance.