In a study recently published in Nature Communications, Scientists from the Novo Nordisk Foundation Center for Bio-Sustainability (DTU) and Yale University investigated how bacteria commonly found in fermentation of ethanol in sugarcane affect the industrial process. By closely studying the interactions between yeast and bacteria, it is suggested that the industry can improve both the overall yield and cost of fermentation processes by paying more attention to the diversity of microbial communities and the choice between good and bad bacteria.
Scientists have dissected the interactions of yeast and bacteria in fermentation of ethanol in sugarcane by reconfiguring every possible combination of the microbial community structure, which covers nearly 80% of the biodiversity present in industrial processes, and especially one bacterium deserves more attention: Lactobacillus amylovorus. But how exactly does this fall into the “wicked” category? The main reason is that it produces a lot of the acetaldehyde molecule, which is used to feed the yeast and thus helps it grow. You could argue that Lactobacillus amylovorus is inherently more generous and participates in a meal, while many other bacteria involved in these processes prefer to simply steal food.
“It works the same way as probiotics that protect bad bacteria from entering the system. And when these bacteria grow, they will grow in an almost symbiotic way with yeast which is very beneficial to the industrial process,” says Philip Lino, a former PhD student at the Novo Foundation Center. Nordisk Bio-Sustainability and Director of Global Research and Development at Anheuser-Busch InBev.
Significant improvement in yield
Hence, companies can benefit from choosing not only the ideal yeast strain to produce, as they already started in the 1990s, but also to select the most suitable bacteria as well, because it is absolutely impossible to get rid of the bacteria that are hanging around no matter what. An effort that can actually pay dividends in a short-term perspective.
By using this probiotic in fermentation of ethanol in sugarcane, it is estimated that the fermentation yield could be increased by three percent. While three percent can seem like a fairly low number, that is definitely not the case. According to the 2019 Brazilian Biofuels Annual, Brazil’s total ethanol production in 2019 was 34.5 billion liters with domestic demand of 34 billion liters making the country home to the largest fleet of cars that use ethanol derived from sugar cane as an alternative fuel to fossil fuels. petroleum.
These numbers indicate that the improved fermentation processes hold great potential. One way to start ensuring more efficient industrial production of ethanol is to implement more targeted methods and move away from a “one size fits all” strategy where sulfuric acid treatment is used without further study to lower the pH and kill bacteria to preserve it. The population is below a certain threshold. This would be economically and environmentally beneficial, says Morten Sommer, professor and head of the group at the Novo Nordisk Foundation’s Center for Bio-Sustainability.
Instead of using a wide range of antibiotics, one must look for a more specific solution as you can keep the good bacteria inside the fermenter. This is definitely a paradigm shift because you are not fighting by definition all bacteria, since some bacteria are really good and your end product greatly improves while also positively impacting your production costs and the environmental footprint. ”