BIOMASS: Exploring Sustainable Fuel and Alternative Power

Living with waste causes hurdles that become unbearable as time goes on. The resulting greenhouse gases such as methane, a significant drive to climate change, and some other artificial chemicals would leave a permanent mark in the atmosphere, contributing to the much feared air pollution. On land, an increase in cockroaches and rodents would increase land pollution, gradually causing health issues for nearby communities. The harmful effects of these natural and plastic wastes are a bane to society, and although the majority of students and individuals worldwide see and dislike these effects, not many can visualize how well these harmful effects could be curbed through a bit of chemistry and engineering.

Ideas for how to solve our waste problem come in various shapes — with various levels of effectiveness. The idea that some of this waste will eventually rot continues to thrive in some communities, with some individuals suggesting that all waste will eventually decompose, no longer presenting a problem. Of course, some waste does rot but the process isn’t in any way pretty or beneficial to the problem. All of this could be avoided and even reversed if we could just reduce the amount of waste but also convert it into something usable, something valuable, something better than risking environmental devastation.

A close up picture of thin slices of pineapple waste mixed with other plant debris
Pineapple plant waste.

As a student, I was fortunate to work with a team of engineers on obtaining valuable products from the waste of fruit (pineapple in particular) through a bit of fermentation, heating and distillation. Our goal was BIOMASS—fuel that is clean and sustainable enough to reduce pollution while providing alternative means of power compared to conventional fuels like fossil fuel.

Biomass is a renewable fuel derived from organic materials and acts as an alternative for producing fuels, heat and electricity. Converting these waste to biomass is essential in producing cleaner fuels and reducing the pollution these waste build. 

We carried out a series of steps and chemical reactions before converting this waste to ethanol.The process of collection involved visits to any polluted environment with a significant amount of fruit waste in order to launch our experiment. We considered the amount of fruit waste to be a gauge of how high our ethanol yield would be.

Research, collection, and grinding

At first, gathering this waste could be unhealthy without taking into consideration proper measures. When working on this project, we used a nose mask to avoid inhaling the foul smell this waste produces, and gloves when gathering fruit waste.

To ensure maximum ethanol production, I worked with a group that researched the amount of alcohol in different fruits at different stages of decay. Ripe fruit waste usually contains more alcohol than their unripe counterparts, hence we used about 2.4kg of ripe pineapple waste retrieved from the waste site. We rinsed off excess dirt and germs with water in preparation for the home grinding appliance we later used to grind the peels.

Grinding this amount of waste mixed with 1.5 liters of water yielded small, moist chunks of pineapple waste which were separated by filtration in order to distinguish the solid chunks from the liquid. The resulting mixture was pure liquid which we termed “the filtrate.”

A digitally rendered image of three large silver cylinders connected as part of the ethanol distillation process
Ethanol distillation model.

Heating

The filtrate was heated for about 3-4 hours in order to produce sugar. This sugar content was measured using a hydrometer. The sugar syrup is then diluted and fermented using Sacchromyces cerevisiae (yeast). Diluting the sugar is a practice performed to prevent the sugar from killing the yeast. 10ml of this yeast was added and mixed with 100ml of 37°C water, then stirred regularly for 10 minutes, before finally being allowed to sit for 3-4 days in a sealed container at room temperature. At intervals, the mixture was manually agitated to ensure proper mixing and fermentation of the yeast with the sugar. 

Fermentation

During fermentation, our liquid produced heat through a gradual stirring process, which yielded alcohol. Research shows a 7-8% by volume ethanol production at 50-70 hours into fermentation, with some studies showing that an 80-100 hour fermentation would yield 8-9 % ethanol. This fermented product has alcohol present and while some use this for the well known Tepache recipe, our goal was ethanol production. With this in mind, our fermented product was heated and separated through fractional distillation, a technique used to separate mixtures of various boiling points.

Fractional distillation

Fractional distillation was only possible due to the difference in boiling points between the alcohol and water present in the fermented product. Definitely, the ethanol present would evaporate before the water due to its lower boiling point (about 78.37°C). The vapor passes through a copper pipe which is rapidly cooled and yields liquid as the end product (through condensation). This liquid is ethanol, although it could contain a bit of water if proper distillation wasn’t carried out.

From this experiment, we successfully reduced both air and land pollution in exchange for ethanol using fractional distillation, a biofuel that is ecologically effective and releases less carbon emissions when used in automobiles.

A long infographic titles "Our Plants." There is a cartoon picture of a tree. Underneath is the text "Here's what they do." Below that is a cartoon of spinning gears. The text reads "Processing of these plant residue (the more the plant, the more the product). Belong that is a cartoon picture of a flame. The text reads "Fermentation yielding liquid for distillation." Below that is a cartoon picture of a black car. The text reads "Distillation and power plant processes leading to minuscule amount of ethanol for automobiles." Below that is more text that reads "However, we can't use Earth's soil solely for biomass producation."
Sustainability cycle infographic.

Sustainability Analysis

But there’s a catch: When reaching our desires for economic, social, and environmental sustainability, there needs to be a valuable and reasonable amount of input to yield the same reasonable amount of output. Unfortunately, this was not the case when producing ethanol from pineapple waste. Our experiment showed that from a 2.5 litres of fermented pineapple juice, we could only obtain about 0.05 litres of ethanol, which is much less than the required amount to even partially replace conventional fuels. 

Continuing to work on producing ethanol with such low yields might mean the possibility of food shortage. The United States Environmental Protection Agency highlights that economic models reveal biofuel use can result in higher crop prices

The large scale ethanol production process is by no means efficient yet and a huge amount of money invested in developing efficient means might also spike the ethanol distribution costs — opposing one of the most adored reasons for producing bioethanol: it’s cheap cost. Our already occupied land and environment would have to be cultivated with a huge amount of crops from which waste could be obtained in order to produce a reasonable amount of ethanol that rivals or completely replaces fossil fuels. 

Our alarming need for transportation fuel alone rises daily, as explained by Tim Searchinger and Ralph Heimlich of the World Resources Institute in their working paper. Large fossil fuel consuming regions have established ambitious biofuel targets that amount to 10% transportation fuel by 2020. If such targets were to go global by 2050, using 30% of a year’s harvest today would only produce about 10% of the transportation fuel needed, making a sustainable food future more difficult. 

We’d be sacrificing a valuable portion of the Earth’s soil to produce a somewhat minuscule amount of valuable biomass required to power our automobiles today. This cost makes the situation rather unwise for such an industrial project by large scale industries. Those same industries could emit large amounts of gases, causing minor water pollution. Although it’s still a debate, our pineapple waste experiment showed that we have not yet achieved the perfect alternative to fossil fuels we all wish for. 

A big power plant with a series of silver silos and long silver buildings. The plant sits on green grass. There is water in the foreground.
Ethanol plant near Mason City, IA. Photo by Jeff Easter.

Our Sustainability cycle

There is irony in the fact that such a simply-made alternative to fuel introduces a new set of such serious problems.

The waste that resides in polluted environments is not enough to produce a desired amount of ethanol for powering vehicles, and yet to increase these wastes for higher yields is unsustainable as well. Using the Earth’s soil to cultivate crops not for food but instead solely for ethanol and BIOMASS production causes its own environmental damage, along with the social issues of acquiring the land and not feeding populations in need. But the experiment which was carried out shows that ethanol production and waste reduction are possible — if not on an institutional level, then at least on an individual one. We can’t produce enough ethanol sustainably for entire regions, but hobbyists could make biofuel for their own personal use and reduce pollution in their society at the very least, making it a rural-based humanitarian service for people deeply affected by environmental pollution.

A new personalized cancer treatment – will ‘GliaTrap’ be able to lure and treat cancer cells to prevent tumor recurrence?

What if you get diagnosed with cancer? What if your beloved family member, partner, or friend gets diagnosed with cancer? The news may fill you with fear and despair. Particularly, what if you get diagnosed with glioblastoma (GBM)? GBM is the most aggressive type of brain cancer with an average overall survival of 15~21 months after the first diagnosis. Moreover, GBM patients’ 5-year survival rate is less than 7%, one of the lowest among all cancers. Although treatment for other types of cancer is becoming more and more successful, current treatment options for GBM are largely ineffective and inevitably result in relapse and death. However, at the Laboratory of Cancer Epigenetics and Plasticity at Brown University and Rhode Island Hospital, we are working on innovative new treatments for GBM. One of these projects is called GliaTrap.

What’s Drug discovery process?

How does a new treatment get discovered? The drug discovery process is divided into three steps: 

1. Drug Discovery and Development. 

2. Preclinical Research 

3. Clinical Research. 

A cartoon image of three grey mountains. One mountain is labeled with "Challenge 1: Drug discovery and treatment." One mountain is labeled with "Challenge 2: Pre-clinical research." One mountain is labeled with "Challenge 3: Clinical research." This last mountain is topped with a green flag that says "Goal."
GliaTrap development plan.

During Step 1, researchers elucidate the mechanisms of disease progression, which leads to the discovery and development of a treatment that inhibits the disease process. Once a potential therapeutic candidate is selected, this candidate will go to Step 2 where researchers test the safety, side effects, how the drug affects the body, how the body responds to the drug, and so forth. Preclinical research requires a different laboratory setting than an Academic Research Lab and it should be monitored by a third party (e.g. the FDA in the US). Once this therapeutic candidate is determined to be safe enough, then this treatment will go to Step 3, Clinical Research, where its efficacy in human patients will be tested. This entire process takes about 10-15 years for a single treatment candidate to become available to patients.

Current therapies for GBM include surgical removal, chemotherapy, radiation therapy, or a combination of those. Each treatment modality has its own advantages and disadvantages. Surgery removes most of the bulk tumor but it cannot remove individual cells, which remain in the brain. Chemotherapy is normally administered to treat these remaining GBM cells, however it is challenging to specifically target the distributed GBM cells without killing the surrounding healthy normal cells. Radiation therapy has similar disadvantages as chemotherapy since targeting only cancer cells without damaging the surrounding healthy normal cells is impossible. As explained above, all the current approaches face huge clinical challenges, which makes GBM currently impossible to treat.

 Innovative cancer treatment “GliaTrap” : GliaTrap lures the cancer cells and attacks them.

To address this challenge, we are developing a new technique for GBM therapy: GliaTrap. GliaTrap basically functions just like a Japanese cockroach trap “Gokiburi hoihoi”, a container that houses foods to attract cockroaches and drugs to kill the attracted cockroaches. For the concept of GliaTrap, you should think of cancer cells in the brain like the cockroaches in my example. (Figure 2). GliaTrap uses a biocompatible material called hydrogel, like the container of the Gokiburi hoihoi, to house food and drugs that lure and kill cancer cells. Food for cancer cells is called a chemoattractant, and GliaTrap uses this molecule to lure the residual GBM cells post-surgery to the vicinity of the empty space, just like a cockroach trap uses food to attract cockroaches. Once these cancer cells are attracted to GliaTrap, GliaTrap uses an anti-tumor agent to kill those cells at the vicinity of the empty space without causing significant damage to healthy cells, just like cockroach traps use drugs to kill the cockroaches. We hope that GliaTrap will be able to eliminate the remaining cancer cells from the surgery to prevent tumor recurrence.

GliaTrap can utilize not only anti-tumor agents, but also lure/use the body’s natural immune cells. Anti-tumor agents in GliaTrap can be replaced with immune cell activators, molecules that boost the ability of immune cells to attack cancer cells. GliaTrap can serve as a new treatment delivery method in concert with surgical removal and chemotherapy. GliaTrap combines targeted capture and drug release to increase therapeutic efficacy and safety by selectively killing the cancer cells that surgical removal and chemotherapy might miss. As a result, GliaTrap could increase the survival rate of GBM patients.

On the left is a cartoon cockroach outside of a cartoon trap that has poison disguised as food inside it. The next panel shows the cockroach entering the trap enticed by the food. The last panel shows the cockroach dead inside the trap due to poison.
How cockroaches mimic the GliaTrap system.

Looking forward, GliaTrap can potentially be applied to other types of invasive cancers that don’t have effective current treatments such as pancreatic cancer. Pancreatic cancer has a similar treatment protocol – surgical removal followed by chemotherapy, radiotherapy, or a combination of those. GliaTrap could be implanted into the empty space created by removal of pancreatic cancer cells, and perform in a similar way as described for GBM by choosing an optimal chemoattractant for pancreatic cancer cells. To ensure the coverage of capturing cancer cells, genetic profiles of cancer cells can be investigated and optimal chemoattractants can be utilized. Chemoattractants and therapies can be selected based on the genetic profiles of cancer patients, and GliaTrap can be tailor-made for each patient. With continued effort, GliaTrap could become a platform for combination therapies for various types of cancers contribute to personalized treatments options.

The current challenge for GliaTrap research.


The GliaTrap project has great potential but as every paradigm shifting discovery, it comes with many challenges. It needs a lot more studies to prove its effectiveness and safety before it can be applied to patients.  Ultimately, with our work at the Laboratory of Cancer Epigenetics and Plasticity, we hope to help patients and their loved ones to no longer view the diagnosis of cancer as a death sentence, but rather as a challenge that can be overcome with the right treatment.

References:

1. Louis, D. N. et al. The 2016 World Health Organization Classification of Tumors of the Central  Nervous System: a summary. Acta Neuropathologica 131, 803–820 (2016). 

2. Toms, S. A., Kim, C. Y., Nicholas, G. & Ram, Z. Increased compliance with tumor treating fields  therapy is prognostic for improved survival in the treatment of glioblastoma: a subgroup analysis of  the EF-14 phase III trial. J Neurooncol 141, 467–473 (2019). 

3. Wang T, Suita Y, Miriyala S, Dean J, Tapinos N, Shen J. Advances in Lipid-Based Nanoparticles for Cancer Chemoimmunotherapy. Pharmaceutics. 2021; 13(4):520. https://doi.org/10.3390/pharmaceutics13040520

4. Tapinos, N., Sarkar, A. & Martinez-Moreno, M. Systems and Methods for Attracting and Trapping  Brain Cancer Cells. (2017).