Submitted to: American Chemistry Society Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 7/1/2002
Publication Date: N/A
Citation: N/A Interpretive Summary: We have made new carbohydrates from sugar, corn, or soybeans. These carbohydrates were found to have "prebiotic" activity, which means they enhance the growth of beneficial bacteria from the lower intestines of humans and other animals, without supporting the growth of harmful bacteria. Although most of the hard scientific evidence is still undergoing review, prebiotics are believed to be useful in human foods by promoting improved digestion and nutrient absorption, reducing the likelihood of diarrhea in infants and travelers, and possibly reducing other diseases of the colon. They may also play similar roles in animal nutrition. Several "prebiotic" carbohydrates are now on the market in Asia and Europe, but they are relatively new to U.S. markets. Most of the current products are not made from U.S. commodity crops, whereas these new products may be made from U.S. commodities such as sugar, corn, or soybeans. This research will have an impact on starch and sugar processors, food companies, feed manufacturers, livestock producers, and consumers in general.
Technical Abstract: Alternansucrase synthesizes an alpha-(1-3),alpha-(1-6)-D-glucan via glucosyl transfer from sucrose. It also synthesizes oligosaccharides containing both types of linkages when acceptor sugars are present. We have used alternansucrase to synthesize oligosaccharides from maltose, maltodextrins, maltitol, cellobiose, raffinose, melibiose, lactose, gentiobiose, and other carbohydrate acceptors. Analysis of the products shows that alternansucrase is better at catalyzing acceptor reactions when compared to dextransucrase and that the structures of the products differ. Whereas dextransucrase generally makes only a single product from any given acceptor, alternansucrase often makes two or more, and in higher yields. Several of these oligosaccharide acceptor products have been isolated and tested for their ability to support the growth of probiotic bacteria, including selected strains of Bifidobacterium spp. and Lactobacillus spp. Certain acceptor products supported growth of probiotic strains but did not serve as substrates for undesirable bacteria such as Salmonella choleraesuis, Clostridium perfringens, or Escherichia coli.