Research shows that the bacteria Propionibacterium freudenreichii produces vitamin B12 much more efficiently when it eats lactate instead of sugar. According to Gram Research analysis, lactate-fed bacteria achieved approximately 100 micrograms of vitamin B12 per gram of wet biomass by maintaining balanced internal chemistry, while sugar-fed bacteria grew larger but produced less vitamin B12 due to chemical constraints. This finding could help food manufacturers optimize fermentation to produce more natural vitamin B12.
Scientists discovered that a special bacteria used to make cheese and yogurt produces vitamin B12 much better when it eats lactate (a type of acid) instead of sugar. According to Gram Research analysis, the bacteria’s choice of food affects how it balances its internal chemistry and decides what to build. When the bacteria eats lactate, it can make about 100 micrograms of vitamin B12 per gram of bacteria. When it eats sugar instead, the bacteria grows bigger but makes less vitamin B12. This finding could help food companies produce more vitamin B12 naturally using fermentation.
Key Statistics
A 2026 laboratory study found that Propionibacterium freudenreichii produced approximately 100 micrograms of vitamin B12 per gram of wet bacterial biomass when fed lactate, compared to reduced yields when fed glucose or fructose.
Research published in mSystems showed that lactate-fed bacteria maintained balanced redox chemistry and enhanced amino acid biosynthesis, while sugar-fed bacteria activated alternative aspartate metabolism pathways to manage chemical stress.
The study demonstrated that carbon source is a key determinant of metabolic state in vitamin B12-producing bacteria, with lactate supporting efficient biosynthesis while hexose sugars imposed redox constraints that reduced vitamin B12 production efficiency.
The Quick Take
- What they studied: How does the type of food (carbon source) that bacteria eat affect their ability to make vitamin B12 and balance their internal chemistry?
- Who participated: Laboratory experiments with Propionibacterium freudenreichii, a bacteria strain commonly used in food production. The researchers analyzed the bacteria’s proteins and chemicals under different feeding conditions.
- Key finding: Lactate-fed bacteria produced about 100 micrograms of vitamin B12 per gram of wet biomass with balanced metabolism, while sugar-fed bacteria grew more but produced less vitamin B12 due to chemical imbalance constraints.
- What it means for you: If you consume fermented foods like certain cheeses or yogurts, understanding how bacteria make vitamin B12 could lead to products with more natural vitamin B12. This research may help food manufacturers optimize production methods, though consumer products would need further development and testing.
The Research Details
Researchers studied a specific strain of bacteria called Propionibacterium freudenreichii that naturally makes vitamin B12. They fed this bacteria different types of food (lactate, glucose, and fructose) and measured what happened inside the cells. The team used advanced protein analysis (called label-free quantitative proteomics) to see which proteins the bacteria made under each feeding condition. They also measured the bacteria’s growth, the chemicals it produced, and how efficiently it made vitamin B12.
This approach is like watching a factory change its production line based on the raw materials it receives. By measuring the proteins (the factory workers), the chemicals (the products), and the overall performance, the researchers could understand how the bacteria reorganizes itself when given different foods.
The study combined three types of measurements: protein levels inside the cells, the bacteria’s physical growth and performance, and the specific chemicals present. This multi-layered approach allowed researchers to build a complete picture of how food choice affects the bacteria’s metabolism.
Understanding how bacteria choose to use different foods is important for biotechnology and food production. Propionibacterium freudenreichii is one of the few organisms that can naturally make vitamin B12, a nutrient many people struggle to get enough of. By understanding the metabolic principles that govern this bacteria’s performance, scientists can optimize fermentation processes to produce more vitamin B12 efficiently. This knowledge could improve food fortification strategies and reduce reliance on synthetic vitamin supplements.
This study used advanced, modern laboratory techniques to measure protein levels and metabolic activity. The research was published in mSystems, a peer-reviewed scientific journal. The findings are based on controlled laboratory experiments with a well-characterized bacteria strain. However, the study was conducted in controlled lab conditions, so results may differ in real food fermentation environments. The specific sample sizes for individual experiments were not detailed in the abstract, which limits assessment of statistical power.
What the Results Show
When bacteria ate lactate, they entered a balanced metabolic state. In this state, the bacteria activated their respiratory system (the cellular machinery that uses oxygen), made amino acids efficiently, and produced vitamin B12 at high levels of approximately 100 micrograms per gram of wet bacterial biomass. The bacteria’s internal chemistry stayed well-balanced, allowing it to dedicate resources to making vitamin B12.
When the same bacteria ate sugar (glucose or fructose), something different happened. The bacteria grew larger and produced more total biomass, but its internal chemistry became constrained. The bacteria couldn’t balance its chemical reactions as easily. Instead of making vitamin B12 efficiently, the bacteria activated a backup system using aspartate metabolism. The researchers propose that this backup system helps the bacteria rebalance its internal chemistry when sugar metabolism creates too much of certain chemical byproducts.
The key difference is that lactate feeding allows the bacteria to maintain what scientists call redox homeostasis, a balanced state of chemical reactions. Sugar feeding forces the bacteria into a constrained state where it must use alternative chemical pathways to survive. This constraint reduces the bacteria’s ability to make vitamin B12 efficiently, even though it grows faster overall.
The research revealed that aspartate metabolism serves as an alternative electron sink in sugar-fed bacteria. This means the bacteria converts aspartate (an amino acid) into other chemicals like fumarate and succinate to manage excess chemical byproducts. This is a clever adaptation that helps the bacteria survive under chemical stress, but it diverts resources away from vitamin B12 production. The study also showed that vitamin B12 production is not simply determined by how much of the vitamin B12-making enzyme the bacteria produces. Instead, it emerges as a system-level property, meaning the entire metabolic network must be in the right state for efficient vitamin B12 synthesis.
Previous research had characterized how oxygen affects this bacteria’s gene expression and metabolism. This new study extends that understanding by showing that carbon source (the type of food) is equally or more important than oxygen in determining the bacteria’s metabolic state. The findings align with broader principles in microbiology showing that nutrient availability shapes cellular metabolism, but they provide specific mechanistic insight into how this particular bacteria balances its chemistry while making vitamin B12.
The study was conducted in controlled laboratory conditions, which may not fully represent what happens in actual food fermentation environments where multiple factors change simultaneously. The abstract does not specify the number of biological replicates or statistical analyses performed, making it difficult to assess the robustness of individual measurements. The research focused on one specific strain of the bacteria, so results may not apply to all strains used in industry. Additionally, the study measured what happened at specific time points, so it may not capture all dynamic changes in metabolism over longer growth periods.
The Bottom Line
For food manufacturers: Consider lactate-based fermentation substrates when optimizing vitamin B12 production in Propionibacterium freudenreichii cultures. This approach shows strong evidence for improving vitamin B12 yields. For consumers: This research supports the potential for naturally fermented foods to contain higher vitamin B12 levels, though commercial products would need to implement these findings and undergo safety testing. For researchers: Use this metabolic framework to guide optimization of other microbial bioprocesses where cofactor or secondary metabolite production is desired.
Food and beverage manufacturers producing fermented products, particularly those making cheese or probiotic supplements. Biotechnology companies working on vitamin B12 production or other microbial fermentation processes. Nutritionists and health professionals interested in natural sources of vitamin B12. Researchers studying microbial metabolism and metabolic engineering. People with vitamin B12 deficiency may eventually benefit from improved fermented food products, though this research is still in the scientific development phase.
Laboratory optimization based on these findings could take 6 to 12 months. Moving from laboratory findings to commercial food production would require 2 to 3 years of additional testing, safety validation, and regulatory approval. Consumers might see improved fermented products with higher vitamin B12 content within 3 to 5 years if manufacturers adopt these insights.
Frequently Asked Questions
Why does the type of food bacteria eat affect vitamin B12 production?
Different foods create different chemical conditions inside bacteria. Lactate allows balanced internal chemistry, freeing resources for vitamin B12 production. Sugar creates chemical stress that forces bacteria to use alternative pathways for survival, diverting energy away from vitamin B12 synthesis.
Can this research help make vitamin B12 supplements from fermented foods?
Yes, potentially. Understanding that lactate-based fermentation yields more vitamin B12 could help manufacturers optimize production. However, moving from laboratory findings to commercial products requires additional testing and regulatory approval, likely taking 2 to 3 years.
Which fermented foods might have more vitamin B12 based on this research?
Fermented foods made with lactate-producing bacteria, particularly aged cheeses and certain yogurts, may have higher vitamin B12 content. However, this research is still in the scientific phase, and manufacturers would need to implement these findings for consumer products.
Does this research apply to all bacteria that make vitamin B12?
This study focused on one specific strain of Propionibacterium freudenreichii. While the findings likely apply to related strains, other bacteria that produce vitamin B12 may respond differently to various food sources.
How long until consumers see products with more vitamin B12 from this research?
Laboratory optimization could take 6 to 12 months, but commercial implementation with safety testing and regulatory approval typically requires 2 to 5 years. Consumers might see improved products within 3 to 5 years if manufacturers adopt these insights.
Want to Apply This Research?
- Track weekly vitamin B12 intake from fermented foods (cheese, yogurt, kefir) in micrograms, noting the type and brand. This creates a baseline to compare against future products optimized using this research.
- Add one serving of lactate-fermented dairy product (such as aged cheese or yogurt) to your daily diet as a natural vitamin B12 source. Log the specific product and amount in the app to monitor consistency.
- Over 8 to 12 weeks, track vitamin B12 levels from fermented foods and monitor energy levels and overall wellness. As optimized products become available, compare your intake and symptoms before and after switching to higher-yield fermented products.
This research describes laboratory findings about bacterial metabolism and vitamin B12 production. It does not constitute medical advice or dietary recommendations. While these findings may eventually inform food production practices, consumers should not change their vitamin B12 intake or supplementation based on this research alone. People with vitamin B12 deficiency should consult healthcare providers about appropriate treatment. Any commercial food products claiming enhanced vitamin B12 content should be evaluated for safety and efficacy through appropriate regulatory channels before consumption.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.