Effect of dried distillers grains with solubles (DDGS) on cholesterol metabolism and xanthophylls bioavailability in rats

Abstract

Dried distillers grain with solubles (DDGS), a co-product generated from the fuel ethanol industry, contain the same nutrients found in corn, except for starch, which has been fermented to ethanol and carbon dioxide. The U.S. Fuel ethanol industry has experienced a rapid increase in production in the past decades with 5 million metric tons produced in 2000 to 42.5 million metric tons produced in 2013 [1]. Currently, DDGS is primarily used as a feed ingredient for livestock and poultry [2], and it has been recognized as an excellent source of energy, amino acids, water-soluble vitamins and minerals for poultry, swine . Considering its high concentration of nutrients, it may have a great potential value as an ingredient in human foods. Therefore we examined several potential human health benefits of DDGS. Specifically, the effect of feeding DDGS, as well as a corn bran fraction and DDGS soluble fraction, on liver cholesterol, total fat, oxidative stress and xanthophyll bioavailability in rats was examined. The results showed that diets containing DDGS and DDGS co-products decreased liver cholesterol, increased bile acids and total neutral sterol excretion, and promoted intestinal fermentation. However, there was no evidence that these products decreased oxidative stress. Due to lack of sensitivity in the methods used, we were unable to assess xanthophylls bioavailability.