The Influence of Selected Novel Glucose -Based Polymers on Nutrient Digestion, Glycemic and Insulinemic Responses, Colonic Fermentation Characteristics, and Ileal and Colonic Microflora Concentrations in the Adult Canine and (Or) Human

Spears, Julie Kristine

Permalink

https://hdl.handle.net/2142/83584 Copy

Description

Title

The Influence of Selected Novel Glucose -Based Polymers on Nutrient Digestion, Glycemic and Insulinemic Responses, Colonic Fermentation Characteristics, and Ileal and Colonic Microflora Concentrations in the Adult Canine and (Or) Human

Author(s)

Spears, Julie Kristine

Issue Date

2005

Doctoral Committee Chair(s)

Fahey, George C., Jr.

Department of Study

Animal Sciences

Discipline

Animal Sciences

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

Biology, Animal Physiology

Language

eng

Abstract

The main objective of this research was to characterize the nutritional effects of including pullulans and 7-cyclodextrin in the diet of healthy adult canines and humans. Pullulan is a linear homopolysaccharide of glucose that is an alpha-1,6 linked polymer of maltotriose subunits. Pullulan is synthesized intracellularly and secreted by the fungus Aureobasidium pullulans . Cyclodextrins are cyclic oligosaccharides composed of alpha-1,4-glycosidic-linked glucose residues. There are three major types of cyclodextrins categorized by number of glucose molecules: alpha-, beta-, and gamma-cyclodextrins are composed of six, seven, and eight glucose units, respectively. Cyclodextrins are produced from hydrolyzed starch syrups via enzymatic conversion using cyclodextrin glycosyltransferases. Cyclodextrin glycosyltransferases are amylolytic enzymes produced naturally by various strains of Bacillus (e.g., B. macerans, B. circulans, and B. firmus). Both the digestible and fermentable portions of pullulans and gamma-cyclodextrin were evaluated. To accomplish this objective, Study 1 was designed to determine the effects of pullulans and gamma-cyclodextrin as components of a complete enteral diet on apparent ileal and total tract nutrient digestibility and fecal characteristics, and to determine the postprandial glycemic and insulinemic responses of pullulans in healthy, adult, nondiabetic dogs. Study 2 was designed to determine the postprandial glycemic and insulinemic response, carbohydrate malabsorption, and gastrointestinal tolerance of low molecular weight pullulan in nondiabetic, healthy, adult humans. Similar data exist on high molecular weight pullulan. Study 3 determined the effects of low doses of supplemental pullulan and gamma-cyclodextrin on food intake, apparent ileal and total tract nutrient digestibilities, microbial populations, and fecal characteristics of dogs. Study 4 was designed to evaluate the fermentation characteristics (gas and short-chain fatty acid production, pH change) of select glucose-based polymers by fecal microflora from healthy adult dogs and humans. Novel incompletely digestible, glucose-based nonstructural carbohydrates varied in their ability to affect nutrient digestion, fecal characteristics, glycemic index, colonic microflora, and fermentation characteristics. The variation in response was due to differences in chemical structure, molecular weight, degree of polymerization, bonding pattern, and stereochemistry. Functional ingredients will no doubt be a topic of increased importance as the links between nutrition and health of humans and companion animals are established and clarified.

Graduation Semester

2005

Type of Resource

text

Permalink

http://hdl.handle.net/2142/83584

Owning Collections