Scientists in Scotland have decoded how a species of seaweed is broken down by gut microbes in red abalone, a marine snail considered a delicacy in many countries.

The revelation is significant because it opens the door to the potential use of seaweed in abalone and other aquaculture to reduce reliance on fishmeal and other unsustainable feed ingredients, according to scientists at the University of Aberdeen's Institute of Biological and Environmental Sciences.

The study, led by Dr. Eirini Sarropoulou and published in the journal Frontiers in Microbiology, analyzed the digestive tracts of red abalone Haliotis rufescens to identify and characterize the microbial community responsible for digesting Palmaria palmata seaweed.

Using a range of molecular techniques, the team identified more than 700 operational taxonomic units (OTUs), which represent different types of bacteria and archaea, in the abalone guts.

Further analysis showed that the majority of the microbial community belonged to the Bacteroidetes and Firmicutes bacterial phyla, which are commonly associated with the digestion of complex carbohydrates such as those found in seaweed.

In addition, the researchers identified specific enzymes and metabolic pathways in the gut microbiota that are responsible for degrading seaweed polysaccharides, proteins and lipids.

This detailed understanding of the microbial digestion of seaweed is expected to support efforts to design and optimize sustainable aquafeeds for abalone and other marine species.

The study also highlights the potential for harnessing natural microbial processes to break down seaweeds and convert them into valuable products such as biofuels, pharmaceuticals and bioplastics.