Molly
Morse

It started with a clam-shell container. Not a lab breakthrough, not a TED stage, not a Silicon Valley pitch deck - a single exhibit at the Monterey Bay Aquarium, back when Molly Morse was in elementary school, devoted to the problem of plastic packaging and what it does to oceans. Something clicked that day, and it never unclicked.

Twenty-odd years later, she is the CEO of Mango Materials, a Vacaville, California company running bioreactors at wastewater treatment plants, feeding methane to bacteria, and collecting the plastic they excrete. That plastic - technically polyhydroxyalkanoate, or PHA - biodegrades in marine environments, because the same kind of microbes that made it can also dismantle it. The ocean does not accumulate Mango Materials' product. It digests it.

The science came out of Stanford. Morse arrived there after completing a BS in civil and environmental engineering at Cornell, and joined a Woods Institute project looking at alternatives to structural wood. That project led her - somewhat circuitously - to studying how PHA-based materials biodegrade under anaerobic conditions. Her PhD supervisor was Craig Criddle, and the research she was doing made her increasingly convinced that PHA had commercial potential far beyond construction composites.

The key insight came when she and fellow PhD student Allison Pieja asked a simple question: instead of feeding bacteria sugar - the standard expensive substrate - what if they fed bacteria methane? Sugar requires breaking down carbon chains and rebuilding them. Methane, pulled straight from a landfill or wastewater facility, just gets built up directly. Cheaper. Cleaner. Already free as industrial waste.

That question became a company. Morse, Pieja, and Anne Schauer-Gimenez - who Morse met at an anaerobic digestion conference during grad school - incorporated Mango Materials in 2010. Morse had spent a brief post-PhD stint consulting for venture capital firms, evaluating other people's sustainability startups. The experience was clarifying. She stopped evaluating and started building.

The early years were grant-funded and scrappy. The company's first government grant came in 2011. In 2012, Mango Materials won the Postcode Lottery Green Challenge, one of the most competitive international green entrepreneurship prizes. The win brought visibility and credibility. It also confirmed that what Morse was doing wasn't academic curiosity - it was a real product in a real market that real investors and governments found worth backing.

Mango Materials produces its PHA pellets under the brand name YOPP - which stands for "You Oust Polluting Plastics." YOPP and YOPP+ are fully compostable, marine-biodegradable, and can be processed through standard plastic manufacturing equipment. Injection molding, fibers, films, packaging, 3D printing - the same pellet, multiple end products. Brands using conventional plastic have a drop-in alternative that doesn't require retooling their factories.

Running a deep-tech manufacturing startup for 15 years without becoming a unicorn requires a specific kind of stubbornness. Morse describes waste facilities - wastewater plants, landfills, agricultural digesters - not as infrastructure problems but as "goldmines of the future." The methane they produce is both an environmental liability and a feedstock. Mango Materials has positioned itself at that intersection: the company doesn't mine ore; it takes what others consider a nuisance and turns it into a polymer supply chain.

By 2022, Biofuels Digest named Mango Materials one of the "Next 50 Companies to Disrupt the World," which was either a recognition of its potential or a note that it had been patiently disrupting things for over a decade without making much noise about it. The same year, Morse was selected as an Unreasonable Fellow through the Unreasonable Impact Americas program - a network for founders whose companies address global challenges at scale.

In 2025, Morse is still at the helm, still based in Palo Alto, still talking about PHA on podcasts - including a 2025 episode of the Big Red Podcast (Cornell's alumni series, a full-circle moment for a Cornell graduate) where she walked through the methane-to-plastic pipeline and the realities of scaling biodegradable polymer production. The company operates from a facility in Vacaville, and sources its methane from the wastewater treatment infrastructure surrounding the Bay Area.

She holds multiple patents. She has published research. She presents at international conferences. And apparently she still finds time to photograph wildflowers and eat dark chocolate - biographical details that appear in Mango Materials' own company profile, which is either charming transparency or the world's most efficient brand storytelling.

The pitch Mango Materials makes to brands is not particularly complicated: here is a biopolymer pellet that works like polypropylene, that your current equipment can process, that your ocean will not be permanently burdened by. The pitch Morse makes to investors is also not complicated: methane is free and abundant, bacteria are cheap to grow, and the market for materials that actually biodegrade is only going to expand as regulations tighten around single-use plastics globally.

What is complicated is the chemistry, the microbiology, the scale-up, the supply chain, the go-to-market. Complicated is what Morse has been doing, quietly and persistently, since 2010. A childhood exhibit about clamshell packaging as the origin point of a biotech startup. It sounds like the kind of story someone invents in retrospect. Except in this case, the bacteria are real, the plastic biodegrades, and the wastewater plant is in Vacaville.