Where Do They Get Cyanocobalamin From?

Over 90% of all manufactured vitamin B12 is produced by companies, primarily in China, using large-scale microbial fermentation. This manufactured form, known as cyanocobalamin, is not found in nature and is the most common form found in supplements and fortified foods.

Quick Summary

Cyanocobalamin is the synthetic form of vitamin B12 created through a large-scale microbial fermentation process using specific bacteria like Propionibacterium and Pseudomonas species. The resulting precursors are converted into stable cyanocobalamin using potassium cyanide and heat. This makes it a cost-effective and reliable source for supplements and fortified products.

Key Points

• Industrial Production: Cyanocobalamin is not a natural nutrient but a synthetic form of vitamin B12 produced on a commercial scale through microbial fermentation.

• Microbial Fermentation: Specific bacteria, such as Propionibacterium freudenreichii and Pseudomonas denitrificans, are grown in large vats to produce cobalamin precursors.

• Chemical Conversion: A controlled amount of cyanide is added to the bacterial cultures to convert the natural cobalamin precursors into the stable cyanocobalamin form.

• Widespread Use: Due to its stability and low cost, cyanocobalamin is the most common form of B12 found in dietary supplements and fortified foods.

• Vegan Source: For those on vegan or vegetarian diets, fortified foods and cyanocobalamin supplements are reliable sources of B12, as natural sources are limited to animal products.

• In-Body Conversion: The human body converts the synthetic cyanocobalamin into the active B12 coenzymes (methylcobalamin and adenosylcobalamin) for use in metabolic processes.

The Microbial Origin of Cyanocobalamin

Cyanocobalamin is the stable, synthetic form of vitamin B12 used widely in dietary supplements and food fortification. Its origin is not from plants or animals, but from bacteria grown in an industrial setting. This process, known as microbial fermentation, is the exclusive method for producing vitamin B12 commercially, as chemical synthesis is too complex and expensive. The entire process is a sophisticated biochemical and industrial endeavor, carried out in massive fermentation vats that can hold over 100,000 liters.

The Fermentation Process Explained

Commercial production begins with selecting and culturing specific strains of bacteria known for their ability to produce cobalamins. The most common bacteria used include Propionibacterium freudenreichii subsp. shermanii and Pseudomonas denitrificans. The process follows a multi-step procedure to ensure a high yield of the vitamin precursor.

1. Preparation of Culture Medium: The bacteria are grown in a sterilized nutrient-rich medium, often containing glucose or molasses as a carbon source, along with a cobalt salt. Cobalt is a crucial component of the vitamin B12 molecule.
2. Fermentation: The bacteria are left to ferment in large vats for several days under controlled conditions. Depending on the bacterial strain, this may involve both anaerobic (oxygen-free) and aerobic (oxygen-rich) phases to optimize production of different cobalamin precursors, such as adenosylcobalamin or hydroxocobalamin.
3. Harvesting and Extraction: After fermentation, the bacterial cells are harvested and the cobalamin precursors are extracted. This often involves a process of heating and filtration.
4. Conversion to Cyanocobalamin: The extracted cobalamin precursors are then treated with a potassium cyanide solution and heat. The addition of cyanide, in a carefully controlled and non-toxic amount, converts the naturally produced hydroxocobalamin into the more stable and shelf-stable cyanocobalamin.
5. Purification: For pharmaceutical-grade cyanocobalamin, the compound undergoes further purification steps, such as chromatography and crystallization, to achieve a high level of purity. Less pure forms are used for animal feed fortification.

The Role of Fortified Foods

For many vegans and vegetarians, fortified foods are a primary source of vitamin B12. These products use the industrially produced cyanocobalamin to enrich their nutritional profile. This offers a reliable alternative to animal-based foods, which contain natural B12 (methylcobalamin and adenosylcobalamin) synthesized by bacteria and accumulated in animal tissue. Common fortified products include:

• Breakfast cereals
• Plant-based milks (soy, almond, oat)
• Nutritional yeast
• Some meat substitutes

Cyanocobalamin vs. Natural B12 Sources

Understanding the distinction between synthetic cyanocobalamin and naturally occurring forms of vitamin B12 is important for consumers, especially those following plant-based diets.

Aspect	Cyanocobalamin (Synthetic)	Natural Vitamin B12 (Methyl- and Adenosylcobalamin)
Source	Produced industrially via bacterial fermentation with the addition of cyanide.	Produced naturally by bacteria and absorbed by animals. Found in meat, dairy, eggs, and fish.
Stability	Very stable and cost-effective, making it ideal for supplements and food fortification.	Less stable when exposed to light and heat.
Metabolism	Must be converted in the body to the active forms, methylcobalamin and adenosylcobalamin.	The active forms used directly by the body for metabolic functions.
Absorption	Some studies suggest better initial absorption, but higher excretion rate.	Potentially higher retention rates in the body.
Risk for Deficiency	Supplementation with cyanocobalamin is an effective way to prevent deficiency.	Vegans and vegetarians risk deficiency without sufficient intake from fortified foods or supplements.

Conclusion: A High-Tech Solution for a Vital Nutrient

Cyanocobalamin is obtained through a carefully engineered, large-scale industrial process that leverages the natural ability of specific bacteria to produce vitamin B12. This process converts the bacterially-produced cobalamin precursors into a stable, cost-effective form suitable for supplements and fortifying a wide array of foods. For individuals on plant-based diets, and those with poor absorption, fortified products and supplements derived from this fermentation process are a reliable way to meet their nutritional needs. While natural forms exist in animal products, the industrial production of cyanocobalamin ensures a consistent and accessible global supply of this critical vitamin. Microbial production of vitamin B12: a review and future perspectives offers additional scientific detail on the subject.

Frequently Asked Questions

Is cyanocobalamin a natural form of vitamin B12?

No, cyanocobalamin is a synthetic, man-made form of vitamin B12. Naturally occurring forms of the vitamin are methylcobalamin and adenosylcobalamin, which are found in animal products.

Which bacteria are used to produce cyanocobalamin?

The industrial production of cyanocobalamin uses specific bacterial strains, with the most common being Propionibacterium freudenreichii subsp. shermanii and Pseudomonas denitrificans.

How is the cyanide in cyanocobalamin safe to consume?

The amount of cyanide in a typical cyanocobalamin supplement is very small and considered safe for consumption. The body is able to effectively process and eliminate this compound.

Do fortified vegan foods get their B12 from cyanocobalamin?

Yes, many foods fortified with vitamin B12, such as cereals, plant-based milks, and nutritional yeast, use industrially produced cyanocobalamin as the enriching agent.

Why is cyanocobalamin so widely used in supplements?

Cyanocobalamin is used in supplements because it is more stable and cost-effective to produce and store than the naturally occurring, active forms of vitamin B12.

Can the body effectively use cyanocobalamin?

Yes, the body can effectively convert cyanocobalamin into the active forms of B12 (methylcobalamin and adenosylcobalamin) to be used for its metabolic needs.

Are there any natural plant-based sources of active B12?

No, plants do not produce vitamin B12. Claims about sources like spirulina and unwashed vegetables are unreliable, and vegans should rely on supplements or fortified foods.