The food additive butylated hydroxyanisole minimally affects the human gut microbiome ex vivo
Johanna M. S. Lemons, Adrienne B. Narrowe, Jenni Firrman, Karley K. Mahalak, LinShu Liu, Stephanie Higgins, Ahmed M. Moustafa, Aurélien Baudot, Stef Deyaert, Pieter Van den Abbeele
Abstract
Butylated hydroxyanisole (BHA) continues to raise consumer concerns. All previous evaluations of this additive have failed to consider its effect on the gut microbiome, even though it enters the colon. An ex vivo model was used to assess the effect of BHA on microbial communities from 24 donors, aged infants to older adults. A dose of 0.35 g/L BHA elicited no statistically significant changes in the functional outputs or community structure for any age group. Although not large enough to affect community diversity, there were some significant decreases at the phylum level. Among the genes most significantly affected by treatment with BHA across age groups are those involved in lipopolysaccharide synthesis and bacterial electron transport encoded by Bacteroidota, Proteobacteria, and Verrucomicrobiota. Given what is known about the intracellular activity of BHA, these genes may hint at a mechanism behind BHA's evident, but minimally detrimental effect on the gut microbiota. • BHA did not reduce diversity or evenness of the gut microbiome for any age group. • Decreased levels of Bacteroidota and Proteobacteria coincided with BHA treatment. • A significant reduction in levels of Akkermansia occurred due to BHA treatment. • Overall, BHA caused a reduction in taxa carrying genes coding for LPS synthesis. • BHA has a minimal, yet significant impact on the gut microbiome.