Project Description

Descrption

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Summary

Oil spills in the ocean are a critical problem in the environment, and immediate action to cope with oil spills is crucial to minimize environmental damage. The most widely used methods to cope with oil spills include using soap-like solvents or polypropylene sheets, but these methods are inherently damaging to the environment due to both their nature (in situ burning replaces marine pollution with air pollution; dispersal increases ground penetration of oil) and the toxicity of the products used (dispersants are often toxic, and absorbing pads cause secondary pollution when landfilled or incinerated after use).

In response to this problem, our project Pinesorb centers around creating an eco-friendly oil absorbent using pine trees, with high hydrophobicity and lipophilicity that allows efficient oil absorption from water. By engineering bacteria(Bacillus subtilis) and yeast(Pichia pastoris) to produce cellulase and finding the optimal mixture of 4 main types of enzymes (cellobiohydrolase I, II, endoglucanase, and beta-glucanase), we would like to emulate the brown-rot fungi process to generate a feasible, practical, and impactful oil-absorbent.

Problems

Due to advancements in coastal navigation and boat safety, large oil spill crises have become rare in recent decades, falling from an annual 24.5 oil spills to only 1.4 by 2010. However, this progress is only superficial. Although the occurrence of large oil spills has decreased, the number of boats has multiplied over the decades and continues to rise at an unprecedented rate due to rapid global development. Of the 210 million gallons of oil entering the ocean each year, 180 million come from natural seepage, which includes operational discharge from ship engines and discharges from land-based sources. As of 2020, 157 billion tonnes of oil exist in the ocean in a form that is nearly impossible to extract using conventional oil absorbents.

A common method to cope with oil spills in the status quo is the use of soap-like solvents to dissolve oil into the water; this creates an unnatural mixture of oil and water that could be detrimental both to the environment and to organisms that come into contact with such chemicals. Another common method, which is also used in large oil spill cleanups, is to use polypropylene sheets, which are essentially plastic sheets, as an oil sorbent. Despite the high absorption rates of polypropylene, their only method of disposal is through burning, which causes detrimental second-degree pollution.

Hence, the significance of a novel environmentally friendly oil absorbent cannot be emphasized enough.

Inspiration

Treating oil spills is a messy, unpleasant, and manual job. Korea met its largest oil spill in 2007, when a crane barge collided with the Hebei Spirit crude carrier, releasing 10,900 tonnes of oil. Even with over 1.2 million workers of local fishermen, volunteers, and the military – a feat of political will and public engagement still touted as one of Korea’s modern miracles – the 2007 oil spill still devastated the local community, the economy, and the ecosystem, including the most precious and fragile mudflats of Korea’s west coast. Our team was inspired by the incident, which exposed a poorly developed arsenal of tools which failed to keep workers safe and replaced the initial environmental harm of the oil spill with their own.

Although oil spill issues have continuously plagued the environment for many years, we believe that now is the perfect time to tackle the problem with our new approach. Very recently, while we were conducting some research on pine trees decomposed by brown rot fungi, we found immense potential for these pine trees to be an oil absorbent due to their high hydrophobicity and oleophobicity. As we are entering the post-pandemic era with increased volume of transportation, oil use, and higher probability of oil spills, it is more important than ever to find environmentally friendly strategies to deal with oil removal. Since the most well-established oil removal methods such as using polypropylene are also environmentally harmful, expanding our project to substitute the traditional oil removal methods seem to be timely and extremely crucial for environmental preservation.

Our Approach

Throughout our project, we focused on using synthetic biology to generate an eco-friendly and efficient oil absorbent using pine trees.

Originally, the oil sorbent we utilized made use of wood bark that had been compositionally altered by brown-rot fungi, which hydrolyses cellulose and hemicellulose, leaving behind a composition primarily of lignin (an organic material that is second only to cellulose in terms of abundance). A heating process without burning the wood bark increases both hydrophobicity and oleophilic, making it incredibly buoyant and effective for oil adsorption. However, the usage of brown-rot fungi wood bark has a significant problem in the necessary biochemical process that has to be taken to naturally generate brown-rot fungi wood bark is time-consuming and difficult.

To overcome this bottleneck, we plan to utilize synthetic biology to engineer bacteria(Bacillus subtilis) and yeast(Pichia pastoris) to produce cellulase. Specifically, this means producing and finding the optimal mixture of 4 main types of enzymes (cellobiohydrolase I, II, endoglucanase, and beta-glucanase). By emulating and improving the brown-rot fungi process through synthetic biology, we hope to offer the oil-sorbent as a feasible, practical, and impactful solution.

Goals

Seoul_Korea intends to utilize Pinesorb in various forms, such as but not limited to booms, pads, and pure powder form. Additionally, we plan to explore alternate forms that Pinesorb can take, such as a water filtration system or even a dishwashing product to remove grease from silverware and glassware.

Through iGEM, we are researching a novel method of breaking down the source wood into powder form. Originally, we utilized brown-rot fungi, which naturally decomposed the source wood into a lignin-based form, stripping away hemicellulose and cellulose. By utilizing synthetic biology, enzymes could be engineered to conduct this process in a much quicker, more efficient manner. Our main focus in our iGEM journey was to efficiently and safely create a product that can turn a 10-year process of natural fungi decomposition into a mere 3-month process led by various engineered enzymes.

Subsequently, this heightened efficiency leads to quicker and less fungi-dependent production of Pinesorb, which can readily be used to lessen the environmental damages of oil spills. Previously, the only eco-friendly alternative to commercial oil sorbents was peat moss, which despite its eco-friendliness was deemed unfavorable due to the lengthy and costly process of growing and harvesting peat moss, as well as the scarcity of peat moss in the natural environment. Pinesorb not only fixes the issue of time and efficiency, but it also breaks the barrier of cost and scarcity, as the only material required happens to be one of the most common types of trees in most nations of the world. Hence, we hope that Pinesorb could hold the potential to be the first realistic eco-friendly alternative to environmentally detrimental oil sorbents.