Goji berries (Lycium barbarum, wolfberry) grow on an evergreen shrub found in temperate and subtropical regions in China, Mongolia and in the Himalayas in Tibet. They are in the nightshade (Solonaceae) family. Goji berries are usually found dried. They are shriveled red berries that look like red raisins. Goji berries are rich in antioxidants, particularly carotenoids such as Beta-carotene and zeaxanthin. One of zeaxanthin's key roles is to protect the retina of the eye by absorbing blue light and acting as an antioxidant. Goji berries have been used for 6,000 years by herbalists in China, Tibet and India to: protect the liver, help eyesight, improve sexual function and fertility, strengthen the legs, boost immune function, improve circulation, and to promote longevity.

Wu HT, He XJ, Hong YK, Ma T, Xu YP, Li HH. Chemical characterization of Lycium barbarum polysaccharides and its inhibition against liver oxidative injury of high-fat mice. 1. Int J Biol Macromol. 2010 Jun;46(5):540-3. Epub 2010 Mar 1.

In this study, we investigated chemical structure of Lycium barbarum polysaccharides and its modulatory effect on oxidative stress in high-fat mice. The polysaccharides mainly contained xylose and glucose. Little amount of rhamnose, mannose and galactose was observed. The Lycium barbarum polysaccharides had IR bands at 800-1200 cm(-1), 1450-1800 cm(-1), 2500-3000 cm(-1), and 3200-3600 cm(-1), which were distinctive absorptions of polysaccharides. Rats are fed with high-fat diet for 2 months. Results showed that blood and liver antioxidant enzymes activities and GSH level in model mice significantly decreased, and MDA level significantly increased (P<0.01) compared to normal control mice. Administration of Lycium barbarum polysaccharides significantly increased antioxidant enzymes activities and decreased MDA level in mice (P<0.01) compared to model group.