New Expectations

FROM THE APRIL ISSUE: With the release of Innova Drive, well-known enzyme developer Novozymes has entered the yeast market for corn ethanol production.
By Lisa Gibson | March 22, 2018

With its new yeast strain for corn ethanol production released earlier this year, Novozymes is trying to “reset expectations” of what yeast can do, says David Hogsett, director of biofuel yeast strain engineering for Novozymes. The well-known enzyme developer has built a yeast platform, Innova, with the help of partner Microbiogen, and released the first strain, Drive, on Feb. 5.

Kim Bertz, senior manager of bioenergy business development for Novozymes, says Innova Drive outperforms other yeast options, tolerating a higher solids content (37 percent, compared with traditional 34), higher temperatures (98 degrees Fahrenheit, compared with 94) and more organic acids. It also reduces fermentation time by up to two hours, according to the company. The cream yeast product reduces losses and raises the benchmark, Bertz says. “It’s become very efficient and stress tolerant so we see more ethanol.”

Brian Brazeau, vice president of commercial biofuels for Novozymes North America, says the company developed its yeast with two main factors in mind: efficient ethanol production and tailored problem-solving. Plants operate to make up for yeast inefficiencies, he says, but Innova Drive is designed to solve those issues, allowing plants to “run how they want.”

Even though Novozymes’ experience lies in producing enzymes, moving to yeast production is a natural next step, Bertz says. It’s crucial that the enzymes and yeast work together in ethanol production, so Novozymes has the right expertise for the job, she adds. Novozymes has supplied a C5 yeast for cellulosic ethanol, but Innova Drive represents its entrance into the corn ethanol market.

Holistic Approach
In developing the Innova platform, Novozymes “leveraged the power of nature,” using natural properties of yeast through breeding and evolution to achieve optimal traits, Brazeau says, calling the tactic the holistic approach. Classical breeding allows mixing of genetic material to achieve natural traits, both primary—glucose consumption—and secondary—temperature, tolerance, etc.

The platform also uses genetic engineering, to prompt the yeast to produce an advanced glucoamylase during fermentation, Hogsett says. The glucoamylase is part of Novozymes’ existing collection of starch-degrading enzymes, and the company says it is twice as effective at converting sugar to ethanol as glucoamylases produced by other yeast options on the market. The mix of classical and genetic engineering tools helps create an optimal yeast product, Hogsett says. “We are not frozen with one or the other. We can draw very broadly on both classical and new, modern tools.”
“Whatever tools we use to get there is not as important as we get there,” says Mads Torry-Smith, director of bioenergy technology development.

Essentially, Innova Drive is built from the “best of the best” yeast in the environment, Bertz says, with the addition of the enzyme. “It’s built to handle just about anything that gets thrown at it.”

Power Through
The success of yeast fermentation performance centers around the balance between the release and consumption of glucose, Hogsett says. Innova Drive’s glucoamylase, along with enzyme products dosed in liquefaction and fermentation, assist in regulating the amount of glucose available to the yeast during fermentation. Innova products are designed for rapid, efficient starch conversion and complete fermentation of glucose to ethanol, reducing occurrence of standard issues with yeast in ethanol plants, according to Novozymes.

“We’re saying you don’t have to live with those downsides,” Torry-Smith says. With a higher heat tolerance, the buffer zone is much larger and helps prevent shutdowns, he says. With a higher acid tolerance, problems can be found and fixed without stopping production. “So the yeast performs excellent on great days and never fails on worse days.”

“We are super excited about the ability of this yeast to power through any upset in the plant,” Hogsett says.

Welcome Competition
Yeast that are genetically modified to express an enzyme like glucoamylase, or that deviate from the traditional, trusted dry yeast, are not new. Lallemand Biofuels & Distilled Spirits released its first strain with both qualities back in 2012. Now in its third iteration of TransFerm, dubbed TransFerm YP3, Lallemand’s yeast products increase yield by up to 4.5 percent above traditional yeast, says Lallemand President Angus Ballard. Almost 90 ethanol producers are using the line of TransFerm products. “We’ve seen a dramatic shift in the market,” he says of the emergence of genetically modified yeast. “It’s refreshing to see that our leadership is being followed.”

Lallemand knocked down the barriers to genetically modified yeast, paving the way for itself, along with competitors, Ballard says. “We had to de-risk it. It’s easy now for new guys to come in.”

Jenny Forbes, yeast and antimicrobials product manager for Phibro Ethanol Performance Group, says genetic modification offers ample opportunity to optimize. “The opportunity with these genetically modified yeasts are endless. Yeast is an amazing organism and you really can get it to express anything.”

But that modification alters robustness in the yeast strain. “Whenever you ask an organism to do something different … there is usually going to be a sacrifice,” she says. Still, as companies that develop yeast continue to improve their strains, the results are getting better and more robust, Forbes says, adding that development will continue and producers will see even more improvements. “The industry would like to see a very high temperature-tolerant yeast,” beyond optimization of existing tolerance, she says. “It is going to continue to change, evolve and grow.”

Ballard says Lallemand comes out with an innovative yeast product every two to three years, with an eye on both increasing yield and retaining robustness. “Yield is king. … It’s an increased capacity time for this industry. Higher yields generate increased profit margins for ethanol producers without the need to invest in capital. You can affect profitability without capital cost.

“We welcome a new competitor into the yeast market,” Ballard says. “Competition is a good thing for the industry.”

Judy Underwood, global market leader for DuPont Industrial BioSciences, agrees. “Any new entrance into this market helps customers achieve their goals.” DuPont released its first yeast strain engineered to express glucoamylase in 2013. The strain was paired with a new glucoamylase in 2016, and in 2017, the company released its newest, highest-yield product, Synerxia Thrive. “Certainly, I think everyone in this industry recognizes that both yield and robustness are important.

“It really depends a lot on the customer and what their needs are,” she adds. “We focus on customers and how we can find the best tailored approach. It’s certainly fine to say we have the most robust yeast, but if customers don’t have problems with infections, that’s not important to them.”

DuPont has two strains in precommercial development now, Underwood says, but she declined to share a timeline for their release. “We want to give our customers the best possible solutions and many options. … More is better: more from us; more from competition. That keeps the industry thriving.”

Clean Goals
During an Ethanol Producer Magazine visit to the Novozymes labs in Franklinton and Morrisville, North Carolina, Managing Editor Lisa Gibson got a peek at the development process. The collection of microbes is held in a freezer with automated capabilities that allow a researcher to punch in codes on a keyboard to identify desired strains, while a robotic arm collects and delivers them through a sliding door. The collection, kept at temperatures below -100 degrees Fahrenheit, can house hundreds of thousands of cell banks, all available on command.

Standing next to his small-scale fermentation research in another lab, Keerthi Venkataramanan, a scientist in microbial physiology, says his goal is to help develop cleaner energy technologies so he can walk around New Delhi in his lifetime without health risk from the highly polluted air.

Brazeau says there is more to come on Novozymes’ Innova platform, strategic development is underway and the company looks forward to releasing more strains.

Author: Lisa Gibson
Managing Editor, Ethanol Producer Magazine