Effect of Fiber Drink Consumption Containing Glucomannan and Isomaltooligosaccharide on Digesta Profile and Gut Microbiota

Dietary fibers have long been recognized for their numerous health benefits, including supporting gut health, aiding in weight management, and reducing the risk of cardiovascular disease. Glucomannan, derived from konjac and porang tubers, has gained attention for its diverse health-promoting properties. However, its application in beverages is limited due to its high viscosity. Combining glucomannan with isomaltooligosaccharide (IMO) is suggested to synergistically enhance functionality, particularly improving gastrointestinal health. This study investigates the functional effects of porang glucomannan and isomaltooligosaccharide-containing fiber drinks (GIFD) on body weight, feed intake, digesta profiles (digesta weight, moisture content, pH) and gut microbiota using in vivo method. Twenty-four male Sprague Dawley rats were divided into 4 groups, including control, inulin, and 2 doses of glucomannan and isomaltooligosaccharide fiber drink (GIFD). Rats were fed with AIN-93M. Adaptation was carried out for 5 days followed by 28 days of intervention. Results indicate that GIFD consumption led to reduced feed intake, likely due to increased satiety effects and glucomannan’s gel-forming ability, resulting in lower body weight gain compared to other groups. While GIFD did not significantly alter digesta weight and moisture contents, it significantly decreased pH values. Analysis of short-chain fatty acids (SCFAs) showed a shift in propionic acid levels, suggesting a beneficial effect on weight control. Moreover, GIFD treatment reduced abundance percentages of enteric bacteria like E. coli and Clostridium, possibly due to increased SCFA production. However, GIFD consumption did not significantly alter sIgA concentration, although there was a trend towards increased levels in GIFD-2, suggesting potential immunomodulatory effects. Overall, it was indicated that porang glucomannan and IMO-containing fiber drinks has the potential to be used as beverages to support body weight regulation and to help maintaining digestive tract health. HIGHLIGHTS Glucomannan and isomaltooligosaccharide-containing fiber drinks (GIFD) reduced feed intake. Consumption of GIFD induced the shift of molar proportion of SCFAs suggesting beneficial health effect. GIFD treated groups showed lower abundance percentages of coli and Clostridium compared to control. GIFD is potential to be developed as weight management product. GRAPHICAL ABSTRACT