[CARDBOARD]
Through our partnership with the Gregory Gilbert Laboratory, pre-pandemic, we discovered how mushrooms decompose food-soiled cardboard through a process similar to composting. We now understand that the substrate for growing mushrooms requires specific carbon to nitrogen ratios to provide the mushrooms with vitality and strength for successful degradation. Experimenting with nitrogen sources such as chicken manure, vegetable scraps, and coffee grounds, allowed for the optimization of the mushroom as an aggressive decomposer. Once COVID hit, we took our research home so that we could continue experimentation outside of the laboratory. In small-scale degradation experiments, we have been growing three species of fungi, in the genus Pleurotus, in 3lb bags of cardboard substrate to assess: rates of mycelium growth, rates of substrate decomposition after mycelial colonization, and the species effectiveness. As we compile data on the growth rates from tested species in Pleurotus, we intend on formulating a standard for quantifying the mycelium growth on the substrate.
As of right now, we are reconstructing our Sustainability-Lab Garden-Sheds Located at Rachel Carson College with cutting-edge solar-powered climate regulation. A microcontroller with temperature and humidity sensors will monitor the optimal indoor mushroom-growing conditions dependent on the life stage of the fungi. CLICK In addition to that, the pandemic has pushed us inside. Though, our team has been producing fenomenal work at home, cultivating fungi and creating top-notch bioreactors. On top of classes and research, we found time enough gain grants from URSTA, NSF-iCorps, and IDEAhub to further our efforts for a cradle to cradle waste system.

[POLYURETHANE]
We began by looking into ways to break down polyurethane because it’s additives make it one of the most toxic plastics. Additionally, the presence of molecular nitrogen makes it difficult to break down, and unsuitable for developing recycling technologies such as pyrolysis and gasification. For this task we have called upon the endophytic fungus known as Pestalotiopsis microspora. This fascinating species was initially observed to degrade polyurethane at high rates. A crude protein extract on cultures of this organism was purified to yield a 21 kDa enzyme of the serine hydrolase class which can degrade polyurethane masses in less than an hour. Optimization of a mycoremediation model for this substrate can allow us to expand into breaking down other plastics and cellulose based products. Some of our accomplishments during the pandemic included inoculation of grain spawn to observe growth kinetics and establish stock of Pestalotiopsis microspora, utilization of shredders and autoclaves for substrate preparation, fieldwork on and around UCSC campus, and procurement of various strains to reduce the chance of genetic variability to skew our experimental results.
Our next step research involves understanding the chemical mechanism by which polyurethane is broken down via an esterase produced by P.microspora and obtaining spectroscopic data on the breakdown products. To date, we have obtained and grown P. microspora which indicated a fast, aggressive growth rate suitable for integration into a bioreactor. To continue the search for other viable mycoremediation species, we keep our eyes set on Mother Nature by consistently performing fieldwork and growing out samples at our sheds located at Rachel Carson College.