How Soybean Milk and Glucose Produce a Heart-Healthy Enzyme
For centuries, the traditional Japanese food natto has been a breakfast staple, prized for its health benefits. The secret to its power lies in nattokinase, a potent enzyme known for its ability to support heart and circulatory health. However, producing this enzyme efficiently and cost-effectively has been a significant challenge. Recent scientific breakthroughs have uncovered a clever fermentation process that not only yields a high output of nattokinase but also creates a valuable bonus product, making the production far more economical.
This article explores the innovative method of using soybean milk and glucose to produce nattokinase, a process that is as smart and efficient as the enzyme itself.
The fermentation process using soybean milk and glucose produces both nattokinase and acetoin simultaneously, creating a more economical production method.
Breaks down fibrin, the primary protein that forms blood clots 2 .
Produced by Bacillus subtilis during soybean fermentation 2 .
Improves lipid profiles and reduces atherosclerotic plaque 2 .
Nattokinase (NK) is a fibrinolytic enzyme—meaning it breaks down fibrin, the primary protein that forms blood clots 2 . Discovered in 1980 by Japanese scholar Yoko Sumi, this enzyme is produced by the bacterium Bacillus subtilis during the fermentation of soybeans into natto 2 . Its potential for supporting cardiovascular health has made it a subject of intense scientific interest.
Cardiovascular diseases remain the leading cause of death globally, and the search for effective, natural solutions is ongoing 2 . Nattokinase has emerged as a promising candidate. Large-scale clinical trials have confirmed that it can significantly improve lipid profiles and reduce atherosclerotic plaque area, all with a favorable safety profile 2 . Unlike some traditional pharmaceutical options, nattokinase offers a multifaceted approach with a lower risk of side effects 2 .
The growing demand for nattokinase in nutraceuticals and pharmaceuticals created an urgent need for safe and high-yielding production strains and cost-effective methods 1 . The core of the problem was economics. Fermentation processes need to be optimized to maximize the output of the desired product while minimizing expenses.
Fermentation processes must maximize nattokinase output while minimizing production costs to make it commercially viable.
Using techniques like UV and chemical mutagenesis to create bacterial strains that produce more nattokinase 4 .
Replacing expensive lab chemicals with low-cost agro-residues like soybean waste, eggshell powder, and brewer's spent grain 4 .
Employing methods like Response Surface Methodology to find the perfect "recipe" of ingredients for maximum enzyme yield 9 .
The goal was clear: find a way to produce more nattokinase without a corresponding surge in cost. The breakthrough came when scientists looked not just at the main product, but at the byproducts of fermentation.
A pivotal study set out to tackle the production challenge head-on by isolating a high-performance bacterial strain and discovering the ideal food source for it 1 .
Researchers began by isolating the best nattokinase-producing strain, named NDF, from 11 different natto samples. This strain was identified as Bacillus subtilis 1 .
The team then investigated which carbon and nitrogen sources allowed this strain to thrive and produce the most nattokinase. After testing various options, they found the winners: glucose as the optimal carbon source and soybean milk as the optimal nitrogen source 1 .
During fermentation, they made a key observation: the bacterium was overconsuming glucose and converting the excess into acetoin, a valuable flavor compound widely used in the food industry 1 .
The process was scaled up in a 6-liter fermenter. The culture medium contained a high concentration of soybean milk (180 g/L) and glucose (105 g/L), and the fermentation was closely monitored over 25 hours 1 .
The experiment was a resounding success. At the 25-hour mark, the fermenter reached its peak production, and both target molecules hit their maximum concentrations simultaneously 1 :
Nattokinase - A remarkably high concentration of the target fibrinolytic enzyme 1
Acetoin - A valuable flavor compound byproduct, improving process economics 1
The nattokinase was verified as pure and active, and the fermentation broth was clean, with very few other proteins present 1 . This dual-output process transformed the economic model, turning what could be waste into a valuable asset.
| Method | Key Features | Economic Note |
|---|---|---|
| Traditional Natto Fermentation | Small-scale, whole soybeans | Low cost, but lower and less consistent yield 2 |
| Statistical Media Optimization | Uses agro-residues (e.g., soybean waste, molasses) | Very low-cost inputs 4 |
| Glucose & Soybean Milk with Acetoin Byproduct | High-concentration substrates in a controlled fermenter | Improved economy due to saleable byproduct 1 |
Both nattokinase and acetoin reach peak production simultaneously at 25 hours during fermentation 1 .
The development of this high-yield, economical production method has significant implications. It paves the way for making nattokinase more accessible for clinical use and as a dietary supplement. Furthermore, the principle of designing fermentation processes to generate valuable byproducts can be applied to other areas of biotechnology, reducing waste and increasing sustainability.
More accessible nattokinase for cardiovascular treatments and supplements.
Valuable byproducts reduce waste and improve process economics.
Future research will likely focus on further optimizing the bacterial strains through genetic engineering and fine-tuning the fermentation conditions to push the yields even higher. The success of using food-grade components like soybean milk and glucose also aligns with a global push for natural and safe production methods for health-promoting ingredients.
In the quest for better heart health, science has not only unlocked the power of a traditional food but has also found a smarter, more efficient way to produce it, ensuring that this ancient remedy can continue to serve modern needs.