Vitamin B₁₂sources and microbial interaction

Abstract

Vitamin B is synthesized only by certain bacteria and archaeon, but not by plants. The synthesized vitamin B is transferred and accumulates in animal tissues, which can occur in certain plant and mushroom species through microbial interaction. In particular, the meat and milk of herbivorous ruminant animals (e.g. cattle and sheep) are good sources of vitamin B for humans. Ruminants acquire vitamin B, which is considered an essential nutrient, through a symbiotic relationship with the bacteria present in their stomachs. In aquatic environments, most phytoplankton acquire vitamin B through a symbiotic relationship with bacteria, and they become food for larval fish and bivalves. Edible plants and mushrooms rarely contain a considerable amount of vitamin B, mainly due to concomitant bacteria in soil and/or their aerial surfaces. Thus, humans acquire vitamin B formed by microbial interaction via mainly ruminants and fish (or shellfish) as food sources. In this review, up-to-date information on vitamin B sources and bioavailability are also discussed. Impact statement To prevent vitamin B (B) deficiency in high-risk populations such as vegetarians and elderly subjects, it is necessary to identify foods that contain high levels of B. B is synthesized by only certain bacteria and archaeon, but not by plants or animals. The synthesized B is transferred and accumulated in animal tissues, even in certain plant tissues via microbial interaction. Meats and milks of herbivorous ruminant animals are good sources of B for humans. Ruminants acquire the essential B through a symbiotic relationship with bacteria inside the body. Thus, we also depend on B-producing bacteria located in ruminant stomachs. While edible plants and mushrooms rarely contain a considerable amount of B, mainly due to concomitant bacteria in soil and/or their aerial surfaces. In this mini-review, we described up-to-date information on B sources and bioavailability with reference to the interaction of microbes as B-producers.

Relationship between metformin use and vitamin B12 status in patients with type 2 diabetes in Japan

“…Given that VB12 levels in the body are dependent on food intake, the risk of VB12 deficiency during metformin administration might also be influenced by diet and nutritional status. The dietary source of VB12 in Japan is mostly fish and shellfish. Serum VB12 levels were found to be significantly greater in individuals eating a fish‐based diet than in those eating a meat diet, with fish and shellfish being important contributors to human VB12 status.…”

Relationship between Vitamin B12 and Cobalt Metabolism in Domestic Ruminant: An Update

“…In the case of vitamin B12 deficiency, the activity of methylmalonyl CoA mutase is affected; methylmalonyl-CoA accumulates and degrades to methylmalonic acid [ 14 , 28 , 31 ]. This is a critical reaction for glucose homeostasis in ruminants, because propionic acid is their most important energy source and will be used as a gluconeogenic precursor ( Figure 3 ) [ 27 , 28 , 32 , 33 ].…”

“…The ruminal flora is capable of producing all the vitamin B12 required by ruminants, as long as there is sufficient cobalt available in the diet [ 19 ]. Therefore, the cobalt content in the diet is the limiting factor, and a deficiency of dietary cobalt easily induces B12 deficiency in cattle and sheep [ 33 ]. The amounts of the vitamin in the rumen content are between 12 to 663 times those available in food [ 21 ].…”

Sensorial and Nutritional Aspects of Cultured Meat in Comparison to Traditional Meat: Much to Be Inferred

“…In most diets, meat provides a large share of various B-group vitamins, especially B12 (8). The latter vitamin is synthesized exclusively by microorganisms (bacteria and archea) and then absorbed and utilized by animals, while plants rarely contain considerable amounts of B12 (54). Hence, people following plantbased diets need to take vitamin B12 supplements in order to fulfill their dietary demands (55).…”