Brown powder, easy to absorb moisture. Lentinan is a substance that extract from the shiitake mushroom. This mushroom is one of the most popular edible mushrooms in the world, production globally being second only to the button mushroom Agaricus bisporus. Lentinan is a beta glucan and its structure is reported as a β(1-3) linked D-glucose with β(1-6) branching point. Lentinan interest is increasing because of its high nutritional value and medicinal properties, traditionally acknowledged by oriental cultures, especially in China and Japan. LENTINAN has been recognized in Japan and China as a food and medicine for thousands of years. Lentinan was isolated from edible shiitake mushrooms used in traditional Asian cooking and herbal medicine. Extracts of these mushrooms are now being incorporated into over-the-counter dietary supplements designed to improve the immune system.