When biomass is converted to biofuel through a heating process called hydrothermal liquefaction, it produces a waste liquid containing nutrients but also toxins. Scientists used a type of fungus called Trametes versicolor to clean up this waste and convert the nitrogen into forms that plants can use. After three days of treatment with the fungus, nitrogen levels that plants can use increased dramatically. Adding helpful bacteria further improved the results, making this waste potentially usable as a fertilizer for growing vegetables hydroponically.