Commercialization of PDMA (Partially Digested Macroalgae) to decarbonize animal feeds by improved control of macroalgae fermentation processes

Farmed marine macroalgae present a carbon negative opportunity for feedstuff production as theydo not require land conversion fertilizers or freshwater. Macroalgae are already used in smallquantities in some animal diets but the complex polysaccharides are largely indigestible. Trials atOcean Era have shown that the microbes from herbivorous reef fish can be used as the inoculum fordeconstruction of macroalgae for aquaculture feeds. The project objective is to identify microbesthat are key to fermentation of tropical macroalgal species as Partially Digested Macroalgae(PDMA) - a partial dietary replacement for aquaculture feeds. We will test a range of microbialisolates to optimize a reproducible fermentation process for deconstructing macroalgae intonutritionally beneficial feedstuffs. Reducing PDMA to a consistent efficient process could providean economic engine for expanded seaweed farming reduce aquaculture feed costs and carbonfootprint. Our proposed work is in line with SBIR Phase I Topic Area 8.8 Biofuels and BiobasedProducts; New Non-food Biobased Products from New Industrial Crops. The focus of the proposedwork is microbial biomass conversion for development of new aquafeed from tropical macroalgae.We will ferment cultured macroalgae with varying combinations of previously-isolated microbesand then conduct feed trials with tilapia. Growth of tilapia will be used to evaluate effectiveness ofeach PDMA additive. With appropriate demonstration and scaling PDMA could make a significantcontribution towards the decarbonization of aquaculture and global greenhouse gas reductiontargets. By establishing a controlled repeatable process we will be able to license these processesto agribusiness.