Abstract

To examine whether two forms of lipid-based nutrient supplements (LNS) or a micronutrient-fortified corn-soy blend were associated with development of the gut microbiota in Malawian infants, to assess the microbiota profiles at the age of 6 and 18 months, and to follow the changes during the 12-month period.

This was a sub-study of a 4-arm randomized controlled trial conducted in rural Malawi. Infants at the age of 6 months were randomized to receive no supplement during the primary follow-up period (control), 54 g/day of micronutrient-fortified LNS with milk protein base (Milk-LNS), 54g/day of micronutrient-fortified LNS with soy protein base (Soy-LNS), or 71 g/day of micronutrient-fortified corn-soy blend for 12 months. Stool samples were collected at baseline (6 months) and end-of-trial (18 months). The 16S rRNA gene was amplified and subjected to multiplex sequencing.

A total of 213 infants had paired microbiota data at 6 and 18 months of age. The Dirichlet-Multinomial test showed no significant difference in microbiota profile between the four intervention groups at either age (each P>0.10). Bifidobacterium longum was most abundant at both ages. Lactobacillus ruminis, Shigella and Salmonella were present. The abundance of Prevotella and Faecalibacterium increased with age (each P<0.001), while Bifidobacteriaceae and Enterobacteriaceae exhibited significant decrease (each P<0.001).

Nutritional supplementation by LNS or corn-soy blend for twelve months did not affect the gut microbiota profile in the rural Malawian context.