Researchers have identified a high abundance of specific species of bacteria that help to break down plant polysaccharides in the gut of Indians1.
They found that in Indians who eat a fibre-rich diet, the majority of gut bacteria belong to Prevotella species. In contrast, in western populations on a low-fibre diet, Prevotella species originate in the mouth and are associated with gut disorders.
The researchers say this provides new insights into the roles of Prevotella species in carbohydrate and fibre metabolism.
Scientists at the Indian Institute of Science Education and Research in Bhopal analysed more than 2,200 genomes and 2.9 million genes of Prevotella species from Indian, western and non-western populations.
The researchers, led by Vineet K Sharma, detected the highest number of Prevotella copri in the gut of Indians. They identified specific regions in the P. copri genome that have genes, which help to metabolise complex plant polysaccharides.
An abundance of P. copri was also observed in other non-western populations who consumed a fibre-rich diet.
A higher number of bacterial species of oral origin, including Prevotella species, was found in the gut of western populations with a low-fibre diet.
The researchers say this could indicate the possibility of a mouth-gut axis in the link between Prevotella and gut inflammation in western populations.
The results could potentially be used to develop new prebiotics and probiotics for improving gut disorders, says Sharma.