Natural emulsifiers lecithins preserve gut microbiota diversity in relation with specific faecal lipids in high fat-fed mice

Synthetic emulsifiers promote metabolic syndrome and considerably alter gut microbiota. Data is lacking regarding natural emulsifiers like plant lecithins, a polar lipid-rich source of 18:3n-3 PUFA (ALA). For 13 weeks, male Swiss mice were fed ALA-replete semi-synthetic high-fat diet (HFD) including lecithin from rapeseed (RL) or soy, vs 2 HFD-controls devoid of lecithin (ALA-replete; low-ALA), vs Chow. Lecithins did not enhance HFDinduced adiposity nor increased inflammation, did not alter gut barrier markers and caecal bile acids, and contributed to n-3 PUFA status. Lecithins improved gut microbiota diversity. RL (10% in fat) even restored alpha-diversity similar to Chow, increased Lachnospiraceae NK4A136, Lactobacillus and Ruminococcaceae UCG-014 groups, and decreased Blautia genus bacteria. The abundance of most beneficial lecithin-enhanced bacteria was positively correlated to the amount of faecal polar lipid-bound ALA. These findings show that lecithins can beneficially affect the gut microbiota in association with changes in lipid residues in the distal gut.

Automated summary

The study found that natural emulsifiers such as plant lecithins, including those from rapeseed and soy, do not promote obesity and inflammation induced by high-fat diet. These lecithins also have no effect on gut barrier markers and caecal bile acids, and contribute to the status of n-3 PUFA. Moreover, they can improve gut microbiota diversity and increase the abundance of beneficial bacteria.