Ya-Ferm

The industrial production of soap in Germany still relies heavily on imported raw materials, particularly tropical oils. As an alternative, regional waste-to-resource strategies offer a promising path forward. This project proposes the use of Yarrowia lipolytica, a robust oleaginous yeast capable of producing lipids and other industrially relevant compounds via biofermentation.
The organic waste used in this model is municipal waste collected from private households. The residual liquids, often byproducts of food preparation and biomass breakdown, are rich in organic matter suitable for microbial cultivation.In Germany, liquid waste from municipal organic streams is handled through several channels: some is reintegrated into composting facilities, some directed to biogas production, and some processed in wastewater treatment plants, where residuals may eventually be incinerated. A portion may end up in landfills or be later leached from landfill sites by rainfall.
This limits their full potential, as the carbon-rich liquids are commonly diverted for one-time energy recovery. A circular approach—if physically and economically viable—could instead enable their reintegration into biological processes, aligning better with long-term sustainability goals.
Conventional biofabrication already plays a dominant role in global chemical production: 99% of the world’s citric acid is made through fermentation using Aspergillus niger, a pathogenic mold. This compound appears everywhere—beverages, detergents, skincare, and even pharmaceuticals—demonstrating how microbial processes have long reached the mainstream of consumption. The use of microorganisms to generate ingredients is no longer niche; it is foundational to modern manufacturing.Unlike A. niger, Y. lipolytica is non-toxic, safe to handle, and does not require sterile conditions. It can metabolize a wide array of substrates—including sugars, fats, glycerol, hydrocarbons, and agricultural residues— and produce saturated and unsaturated fatty acids, organic acids, polyols like

erythritol, aroma molecules, terpenes, lipases, and other biochemicals.Depending on the nutrient input, fermentation conditions (such as pH, oxygen saturation, and temperature) can be tuned to guide metabolic pathways and create specific products. This adaptability makes Yarrowia an ideal candidate for local, circular production systems that valorize waste and reduce dependence on monocultures or imported feedstocks.
The production process begins with the collection and separation of organic waste liquids. These are filtered and split into aqueous and lipid phases. Cultivation takes place on the aqueous fraction, with Y. lipolytica converting the available organics into microbial oil and secondary metabolites. The fermentation is optimized for yield, and products are harvested using mechanical in vivo separation methods—streamlining recovery and eliminating post-process sterilization steps. Lipids are then extracted through solvents or cold pressing, purified, and directed toward downstream uses such as saponification, where they’re mixed with alkali to form soap and glycerol. Additional compounds from the fermentation process—such as aroma agents or acids—can be incorporated into the final product, resulting in a fully microbial, waste-fed soap.
Beyond soap, Yarrowia lipolytica holds potential across numerous sectors: from biosurfactants and emulsifiers to biofuels and specialty chemicals. Its ability to metabolize various substrates allows it to transform what was once considered unusable waste into valuable product ingredients. This metabolic versatility is key to the flexibility of circular chemistry, where regional specificity and feedstock availability can shape production outcomes.
By integrating biotechnology with waste management, this process outlines a scalable, ecologically sound alternative to conventional manufacturing. It not only substitutes imported materials with local waste but also redefines the value chain—from household waste to high-quality biochemicals.