Tech
đ„Pow.bio CEO: Continuous fermentation can deliver âmulti-fold increases in productivityâ
These days, you can engineer microbes to produce pretty much anything, although it doesnât always make commercial sense, says Berkeley-based startup Pow.bio. But could a continuous, rather than a batch approach, change that equation?
While it doesnât make sense for every ingredient, says cofounder and CEO Shannon Hall, running a fermentation process more like an assembly line than a series of cookie batches can enable âmulti-fold increases in productivityâ and enable firms to cut costs by using smaller, more efficient bioreactors to achieve the same output.
AgFunderNews caught up with Hall at the recent SynBioBeta conference in San Jose to find out moreâŠ
Batch vs continuous processing
In a traditional batch precision fermentation process, microbes proliferate (the growth phase) until they reach critical mass in a fermentation tank and are then triggered to start producing a target molecule via a change in the media (the production phase). The batch is then completed, the ingredient is extracted, the tank is cleaned, and the whole process starts all over again.
This, claims Pow.bio, is slow and repetitive. Every time you set up, you need to sterilize everything, grow the cells, trigger them to produce the product, harvest it, and repeat this process over and over and over.
In contrast, Pow.bio has found a way to maintain microbes in an ultra-productive state for weeks in a process it claims can cut capex costs and increase biomanufacturing capacity by orders of magnitude by combining continuous fermentation with advanced control methodology.
Decoupling the growth from the production phase
Pow.bioâs platform effectively decouples growth [of the host microbes] and production [of the target ingredients], âsolving the problems of contamination and genetic drift,â claims Hall, who cofounded Pow.bio with microbiologist Dr. Ouwei Wang in 2019.
âWeâve broken fermentation into unit operations so that we can focus on the performance parameters in each step. We focus on growth, then on production, and then on product recovery, so we can have a true conveyor belt of cells in, product out.
âIn doing so weâve created an environment that is unlikely to induce mutation in the first stage, and weâve created an environment that resists contamination in the second stage. And in practice, weâre able to measure that there arenât contamination events or that there arenât genetic mutation events.â
She explained: âThereâs a small bioreactor thatâs driving growth and a larger bioreactor thatâs all about production, and a connection between the two. We have put an enormous amount of engineering into the software and the hardware to manage the rate of flow. And then we are constantly recycling cells, recovering product and managing the biomass. So all of that is built into our system and managed by autonomously driven software.â
The business model
The aim is to license and support Pow.bioâs technology in multiple environments, said Hall, who raised a $9.5 million series A round led by Re:Food and Thia Ventures last fall taking the startupâs cumulative funding to $13.5 million.
âWe do services for proof of concept, and we do services where we make small amounts of material from grams to hundreds of kilos. From there, the math and the techno-economic analysis is going to help you understand: Is this something I want to own? Is this something I want to rent?â
The stacked risk problem in biomanufacturing
But if continuous fermentation tech like this is such a no brainer, why isnât everyone doing it? And given that most startups rely on contract manufacturers for scaleup, doesnât this require buy in on their part?
According to Hall: âI think people have plenty of risk already and the infrastructure is already built for fed-batch approaches⊠itâs a stacked risk problem. For a long time people have been like, Hey, letâs work the incumbent process because our energy, our money, our vision, is all about a design platform, our end product.â
But the benefits of a continuous process are clear, she added: âFundamentally, you can build a smaller facility to generate the same amount of output. So youâre clearly going to have a better return on invested capital and a faster internal return rate.
âWhen we model continuous systems using Pow.bio technology for a greenfield site, we find that weâre getting 30% lower at the least, and sometimes, 70% lower costs.â
She added: âNobody wants to pay for the capex to build infrastructure. Everybodyâs looking around the table wondering who else could pay? Maybe this is a government initiative? In fact, I donât think there will be one payer. I think that thereâs an opportunity to pull interested parties together to make sense of it all.â
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