Barnharst, Tanner2020-05-042020-05-042018-02https://hdl.handle.net/11299/213066University of Minnesota M.S.B.A.E. thesis. February 2018. Major: Bioproducts/Biosystems Science Engineering and Management. Advisor: Bo Hu. 1 computer file (PDF); ix, 92 pages.The world population will reach 9 billion people by 2050 or sooner and as a result, we must produce 70% more food than we currently are. This food challenge lends itself to many innovative solutions. In this thesis, the use of microorganisms to produce higher value animal feeds is examined. The current challenge in intensive aquaculture is to control the level of nutrient pollutants in the wastewater and provide sustainable sources of proteins for feed. A synthetic lichen type biofilm was developed to have the fungus Mucor indicus and the microalga Chlorella vulgaris grow together on a polymer matrix referred to as a “mycoalgae” biofilm. When the biofilm grows, it takes up phosphorus and nitrogen compounds and converts them to proteins and other cellular products. It cleans the water from nutrient pollutants as the algae are attached to the biofilm leaving purified water at the end of the process. Under 25 mg L-1 total ammonia-N (TAN) conditions, the biofilm reduced TAN to undetectable limits within 48 h with over 69% of the TAN reduction taking place by 24 h. The biofilm reduced levels of phosphate-P from 15 mg to undetectable limits within 24 h. Under the same conditions, 860 mg of dry mycoalgae biomass was generated at the end of the process on 16 cm2 of mesh and 100 ml of culture media. This process allows for easy harvesting of the algae with no energy intensive process of separating the algae from the supernatant. The generated biofilm is composed of two organisms that have been shown to positively aid fish health when included as a feed supplement. Secondary Fermentation of Corn Ethanol Co-Products for improved Amino Acid Qualities In 2016, 5.28 billion bushels of corn were used to produce about 14.79 billion gallons of ethanol in the United States. As a result, about 36 million tons of Dried Distillers Grains with Solubles (DDGS) were manufactured and fed to livestock 1. DDGS are a common feed supplement in cattle rations as it is inexpensive and has positive feeding characteristics. One of the drawbacks of DDGS is that it is lacking in in key amino acids such as tryptophan, arginine, and lysine. Historically these amino acids have been supplemented by external addition of feed grade amino acids to rations. The research carried out attempts to fortify DDGS with higher amounts of key amino acids through secondary fermentation of Wet Distillers Grains by fungi. When cultured on WDG the fungi consumes carbohydrates, which are unavailable to livestock, and converts the carbohydrates to proteinaceous biomass, which serves to close the amino acid gap in corn ethanol co-products. The fungi used are Generally Regarded as Safe (GRAS) and have been used to produce feed ingredients historically. Because of the research, more sustainable forms of animal feed will be produced due to the improved feeding value of the co-productsenAnimal feedBioremediationChlorella vulgarisMucor indicusMycoalgae biofilmRhizopus oryzaeThesis or Dissertation