Niacin can be synthesized from tryptophan and vitamin K can be synthesized by bacteria in the Gi tract.
The (GI)gastrointestinal tract is described as the tract or passageway of the digestive system that leads from the mouth to the anus.
The GI tract is known to contains all the major organs of the digestive system, in humans and other animals, including the esophagus, stomach, and intestines.
The gut in humans is known to harbors bacteria that produce B vitamins, including biotin, cobalamin, folate, niacin, pantothenate, pyridoxine, riboflavin, and thiamin, but in limited amount.
Vitamins can be synthesized by the helpful bacteria living inside of us. The bacteria in the gut can make some of the vitamin K and B vitamins that our body needs, though we still need to get these vitamins from food as well.
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