A simplified method for preparing linear isomalto-oligosaccharides

Will isomalto-oligosaccharides, a well-established functional food in Asia, break through the European and American market? The status of knowledge on these prebiotics

This critical review article presents the current state of knowledge on isomalto-oligosaccharides, some well known functional oligosaccharides in Asia, to evaluate their potential as emergent prebiotics in the American and European functional food market. It includes first a unique inventory of the different families of compounds which have been considered as IMOs and their specific structure. A description has been given of the different production methods including the involved enzymes and their specific activities, the substrates, and the types of IMOs produced. Considering the structural complexity of IMO products, specific characterization methods are described, as well as purification methods which enable the body to get rid of digestible oligosaccharides. Finally, an extensive review of their techno-functional and nutritional properties enables placing IMOs inside the growing prebiotic market. This review is of particular interest considering that IMO commercialization in America and Europe is a topical subject due to the recent submission by Bioneutra Inc. (Canada) of a novel food file to the UK Food Standards Agency, as well as several patents for IMO production.

Immunochemical and related interactions with dextrans reviewed in terms of improved structural information

Structurally diverse dextrans from Leuconostoc mesenteroides and related bacteria have been used extensively in fundamental immunochemical studies such as induction and characterization of anti-dextran antibodies, as well as in studies of their interaction with pneumococcal antisera, normal bovine serum, concanavalin A, dextran-binding myeloma immunoglobulins and hybridoma antibodies. The inherent lack of specificity of structural data obtained by POSA and general lack of insight into other limitations of these analyses has often led to inaccurate and superficial interpretations. Proper interpretation of past and future studies necessitates pointing out previous inadequacies of dextran structural data and detailing more recently acquired structural information on the dextrans. Unambiguous terminology has been achieved by a new system of linkage symbols that includes the designation of structural positions, such as (1----3; l)- and (1----3; b) as linear-chain and branch-point positions, respectively. Results of immunological studies are reviewed. Improved interpretations and correlations are made on the basis of structural data from MSA and several other techniques which have become available on the dextrans.

p-Nitrophenyl alpha-D-glucopyranoside, a new substrate for glucansucrases

p-Nitrophenyl alpha-D-glucopyranoside has been shown to be a substrate for the glucansucrases of various strains of Leuconostoc mesenteroides and Streptococcus mutans. The products from a digest of p-nitrophenyl alpha-D-glucopyranoside with L. mesenteroides B-512F dextransucrase were found to include dextran, a series of p-nitrophenyl isomaltodextrin glycosides, and p-nitrophenyl nigeroside. The kinetics of the reaction were non-Michaelis-Menten, possibly because p-nitrophenyl alpha-D-glucopyranoside has a dual role in the reaction as both a D-glucosyl donor and acceptor.