By: Lila Hoachlander-Hobby
Did you know that making one bottle of olive oil generates liters of toxic waste? Olive mill wastewater (OMWW) is a nasty byproduct of olive oil production that is difficult to dispose of and lethal to plants and aquatic life. In the Mediterranean region, where more than 95% of the world’s olive oil is produced, the annual volume of OMWW is enormous, enough to fill thousands of Olympic-size swimming pools!
Olive mills are often family-run businesses with limited resources; without an efficient way to detoxify OMWW, it is left to evaporate in large ponds, sprayed on agricultural roads, or dumped into waterways. However, as environmental regulations become stricter, these disposal methods are no longer compliant. Accumulation of toxic OMWW forces olive mills to pause production, putting severe economic strain on the families that rely on the olive oil industry for their livelihood.
Zaytounic is an early-stage climate tech startup tackling the OMWW problem by using microbes to convert OMWW toxins into bioplastics. This summer, through the UW Graduate School Industry Internship Program, I joined Zaytounic as a Microbiology Intern, a sabbatical from my PhD research in the Cellular and Molecular Biology Graduate Program as part of Bill Bement’s lab at the Center for Quantitative Cell Imaging. My goal for this internship is to gain invaluable experience in the biotech field and help find a microbe-based solution for the growing OMWW environmental problem.
Part of what makes OMWW a dangerous pollutant is its high concentration of phenolic compounds, which are antimicrobial and therefore very difficult to biodegrade. However, there are some microbes that are resistant to phenolic compounds and amazingly convert these compounds into a biodegradable plastic called polyhydroxyalkanoate (PHA). PHA functions just like petroleum-based plastics, but it’s fully biodegradable and doesn’t break down into harmful microplastics. Zaytounic’s solution is to detoxify OMWW by using phenol-resistant microbes to biodegrade phenolic compounds and convert these toxins into PHA. This will allow olive millers to comply with environmental regulations and prevent costly stoppages in olive oil production. As a bonus, detoxified OMWW can then be re-used as irrigation water, a scarce resource for arid Mediterranean olive orchards. Additionally, this solution will result in low-cost, waste-derived PHA that can be used to make eco-friendly biodegradable products.
As a Microbiology Intern this summer, I am optimizing culture conditions to select for phenol-resistant microbes and identifying the most efficient ways for microbes to convert phenolic compounds into PHA. Rachel Rovinsky, the other Zaytounic Microbiology Intern, and I are doing these foundational microbiology experiments at Forward BIOLABS, a collaborative lab environment for startups in the Madison, WI area. A Science Lead, Gavin Golas, has recently joined the team, and we are advised by an incredibly supportive and optimistic leadership team, Ghassan Hammad (Zaytounic CEO), and Ayelet Nir Shtaier (Zaytounic Business Lead).
I’m so grateful to have this internship opportunity because I believe that harnessing nature to tackle complicated environmental problems is an innovative and hopeful solution for remediating pollutants in our environment. I’m looking forward to learning more about applied biotechnology and creating sustainable solutions to complex real-world problems.
If you’d like to hear more about my and Zaytounic’s progress over the summer, stay tuned for the second part of this blog, where I’ll give an update on our accomplishments, challenges we faced, and future steps. Feel free to also follow along on the Zaytounic LinkedIn page and check out the Zaytounic website!