Human faecal microbiota develops the ability to degrade type 3 resistant starch during weaning

Area of Science:

• Microbiology
• Gastroenterology
• Nutritional Science

Background:

• Human colonisation by bacteria begins at birth, with feeding type significantly shaping early microbiota composition.
• Microbiota diversification occurs during weaning, eventually resembling adult gut flora.
• Investigating the capacity of colonic microbiota across different age groups to ferment resistant starch (RS) is crucial for understanding digestive health.

Purpose of the Study:

• To determine the fermentative capabilities of human colonic microbiota from various age groups using resistant starch (RS).
• To compare the fermentation of RS type 3 (RS-3) and lactulose by infant, adult, and elderly gut microbiota in vitro.

Main Methods:

• Faecal samples were collected from breast-fed infants, formula-fed infants, weaned infants, adults, and the elderly.
• A standardized in vitro batch fermentation method was employed to assess fermentability.
• Metabolite production and substrate degradation were measured to evaluate fermentation efficiency, using RS-3 and lactulose as substrates.

Main Results:

• Human microbiota across all tested age groups efficiently fermented lactulose.
• Resistant starch type 3 (RS-3) was resistant to fermentation by microbiota from both breast-fed and formula-fed infants.
• Microbiota from weaned infants demonstrated complete RS-3 degradation, albeit at a slower rate than adults; fermentation slightly decreased in the elderly.

Conclusions:

• Human fecal microbiota universally ferments lactulose effectively in vitro.
• The capacity to degrade resistant starch type 3 (RS-3) is acquired during the weaning period.
• Further research is needed to explore potential health benefits associated with RS-3 fermentation and short-chain fatty acid production during weaning.