Earth-to-marine-to-earth virtuous cycle: Harnessing residual biomass of animal origin for terrestrial-marine integrated circular economy (ONE EARTH)

Project Information

ONE EARTH

Grant agreement ID: 101135559

DOI

10.3030/101135559

EC signature date 13 May 2024

Start date 1 June 2024

End date 31 May 2028

Funded under

• Food, Bioeconomy Natural Resources, Agriculture and Environment

Total cost

€ 3 999 971,25

EU contribution

€ 3 999 970,75

Coordinated by

ALMA MATER STUDIORUM - UNIVERSITA DI BOLOGNA
Italy

Periodic Reporting for period 1 - ONE EARTH (Earth-to-marine-to-earth virtuous cycle: Harnessing residual biomass of animal origin for terrestrial-marine integrated circular economy (ONE EARTH))

Reporting period: 2024-06-01 to 2025-11-30

Summary of the context and overall objectives of the project

Several industrial sectors require large and steadily increasing amounts of biological ingredients, which are currently mostly obtained through intensive livestock production and fish farming. These practices exert significant pressure on the environment and generate substantial quantities of organic waste. The overall objective of the ONE EARTH project is to develop and assess sustainable and feasible solutions to replace key ingredients derived from intensive farming by exploiting abundant, readily available, and currently underutilized animal-derived farm residues.

Cheese whey (CW), the most abundant by-product of the dairy industry, fish scales (FS) and bones (FB), and chicken feathers (CF) were identified as target residues, while dietary long-chain polyunsaturated fatty acids (PUFAs) and protein fractions represent the target ingredients. Indeed, PUFAs, commonly sourced from aquaculture and overfishing, as well as proteins providing essential amino acids, are crucial components of human and animal diets and key ingredients for food and feed products. Furthermore, they can be used in the formulation of high-value, non-edible chemicals of interest to the fertilizer, cosmetic, personal care and adhesive sectors.

ONE EARTH promotes the interconnection of aquatic and terrestrial farming systems through integrated circular value chains, valorising terrestrial biomass for aquaculture inputs and marine biomass for terrestrial products. In particualr, CW is used for the biotechnological production of PUFAs for fish feed, while CF and FB are exploited as protein sources for cosmetics, personal care products, and bioadhesives. PUFA production involves sequential fermentation processes generating a CO2-rich gaseous effluent, which is further utilised for cultivating PUFA-accumulating algae. CF and FS are processed through microbial, enzymatic, and chemical hydrolysis, while FB are treated via an innovative thermochemical process, together with organic residues from other project units, to produce phosphorus-rich fertilizers.

Dedicated tests in relevant environments will assess the safety and quality of developed products, as well as the economic, environmental, and social sustainability of the integrated value chains. Compliance with regulations and standards will also be evaluated to identify opportunities for industrial uptake and new business development.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Three PUFA production strategies were established and evaluated by testing yeasts, bacteria, and algae as potential biological PUFA accumulators.
Yeasts and bacteria were screened for their ability to grow on pretreated CW, which was preliminarily fermented to generate an effluent rich in volatile fatty acids (VFAs). Once one yeast and one marine bacteria were identified as promising PUFA producers, their growth was tested on fermented CW and they were able to convert VFAs into PUFAs efficiently. Notably, the bacterial strain was also able to produce the long-chain C20 eicosapentaenoic acid (EPA), which is a key component in fish feed formulations.

In parallel, algae were cultivated in an innovative membrane-based photobioreactor using a CO2-rich stream mimicking CW pre-fermentation off-gas. The developed process exerted improved performance compared with those of conventional photobioreactors, and the tested algal strain showed effective PUFA accumulation comparable to yeast-based processes.

Given PUFA sensitivity to heat and oxidation, mild and selective enzymatic esterification was applied to improve stability and functionality of target ingredients. Microbial PUFA-rich oils were successfully converted into fatty acid alkyl esters using lipase enzymes, and obtained esters will be employed in the formulation of products for cosmetic and personal care applications.

Protein fractions were obtained from CF and FS via microbial, enzymatic, and chemical hydrolysis. Bacteria from extreme environments (marine and desert ecosystems) produced non cytotoxic hydrolysates with high protein content as well as antimicrobial and antioxidant and enzymatic activities. Moreover, a cost-effective membrane-based post hydrolysis treatment enabled the separation of distinct bioactive fractions, including antioxidant compounds and enzymes, allowing their potential use in different and specific end-product formulations.

Several proteolytic enzymes were also effectively employed for CF hydrolysis, yielding peptide fractions with different molecular weights and, consequently, diverse application potential. A feasible protocol was developed to allow the direct addition of proteolytic enzymes to CF solutions without the need for intermediate purification steps.

Finally, chemical hydrolysis approaches were evaluated using both acidic and alkaline treatments. Alkaline hydrolysis proved more effective, enabling faster processing and the production of longer protein fragments. Novel strategies aimed at achieving more selective chemical protein cleavage are currently under development.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Once PUFA and protein-rich fractions are obtained from selected residual biomass, they can be used as ingredients in the formulation of target end products. This approach includes product testing and validation, as well as the evaluation of technical feasibility. In parallel, the economic, social, and environmental sustainability of the associated value chains must be assessed. Finally, the development of policy recommendations represents a key requirement for the development and evaluation of biorefinery approaches aligned with the project objectives.

The formulation of fish feed, bioadhesives, and cosmetic and personal care products requires defined critical quantities of ingredients. Therefore, scaling up the processes for PUFA and protein fraction production is essential to supply end users with the required raw materials.

Assessments of the environmental impacts associated with the production of final products are currently essential, as environmental sustainability is a prerequisite for market commercialization. In addition, Life Cycle Costing (LCC) analyses will be conducted to evaluate total product costs from inception to end-of-life. Through these analyses, the project’s final products will be benchmarked against existing alternatives in order to assess their market potential. Potential social benefits will also be considered in terms of societal advancement and innovation.

Relevant legislation, standards, and industry guidelines influencing the technologies and products developed within the ONE EARTH project will also be reviewed. Furthermore, safety and health aspects related to the conversion of residual biomasses of animal origin into high-value ingredients will be further investigated. Accordingly, the authorizations required for market access will be evaluated.

the logical framework of the project highlighting biomass transformation routes and value chains