Vitamins and Nutrition

Brewer's yeast is often used as a source of B-complex vitamins, chromium, and selenium. The B-complex vitamins in brewer's yeast include B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B9 (folic acid), and H or B7 (biotin). These vitamins help break down carbohydrates, fats and proteins, which provide the body with energy. They also support the nervous system, help maintain the muscles used for digestion, and keep skin, hair, eyes, mouth, and liver healthy.

Plants and animals do not have the capacity to synthesize vitamin B12 by their own. But the microorganisms like Saccharomyces cerevisiae ( contains vitamin B12 but there is no clear answer about the source of synthesizing vitamin B12 in this yeast. But it synthesizes vitamin B12.), acetobacter and also by the mushrooms Agaricus. Thus, the correct answer is option D.

Vitamin B$ _{12}$ cannot be made by plants or animals as only bacteria have the enzymes required for its synthesis. Members of the genus Propionibacterium are widely used in the production of vitamin B$ _{12}$.

Escherichia coli are Gram-negative, facultative aerobic bacteria. They are common inhabitant of human gut. These strains of E. coli are harmless. They form the part of the normal microbiota of the intestine. They live in symbiotic association. They benefit hosts by producing vitamin K$ _2$ and preventing colonization of the intestine with pathogenic bacteria.

Riboflavin (vitamin B$ _{2}$) is part of the vitamin B group. It is the central component of the cofactors FAD and FMN and as such required for a variety of flavoprotein enzyme reactions including activation of other vitamins. Various biotechnological processes have been developed for industrial scale riboflavin biosynthesis using different microorganisms, including filamentous fungi such as Ashbya gossypii, Candida famata and Candida flaveri, as well as the bacteria Corynebacterium ammoniagenes and Bacillus subtilis. Strains of yeast of the species Candida famata also used to synthesis ribiflavin. Thus, option C is correct. Microorganism Acetobacter is used to yield ascorbic acid. Thus, option D is wrong. Yeast does not yields tocopherol and vitamin B$ _{12}$. Thus, option A and B are wrong.

The liver is a major storage site for fat-soluble vitamins (A, D, E, K) and is involved in the synthesis of certain clotting factors related to vitamin K.

Fat builds up in the liver cells, when the liver fails to break down, transfer and store fat effectively, causing abnormal liver function and inflammation, which can lead to liver scarring (known as cirrhosis). The main pigment in bile, bilirubin, is a waste product that is formed from hemoglobin (the protein that carries oxygen in the blood) and is excreted in bile. About half the bile secreted between meals flows directly through the common bile duct into the small intestine. The rest of the bile is diverted through the cystic duct into the gallbladder to be stored. Liver stores the fat soluble vitamins (A,D, E & K) and Vit B12.

Vitamins are organic compounds required in small amounts for various metabolic processes. Humans generally lack the biosynthetic pathways to produce most vitamins.

Most vitamins found in nature can be extracted; synthetic production is usually chosen for cost, consistency, environmental impact, or availability, not because they do not exist in nature.

Escherichia coli (E. coli) bacteria residing in the human large intestine synthesize vitamin K (specifically vitamin K2), which is crucial for blood clotting and bone health.

Vitamin D is synthesized in the skin when it is exposed to ultraviolet B (UVB) radiation from sunlight, which is why it is often called the 'sunshine vitamin.'

Vitamin C is a water-soluble vitamin, meaning it dissolves in water and is not stored in the body in large amounts. Vitamins A, D, and E are fat-soluble.

Cyanocobalamin (Vitamin B12) is synthesized by symbiotic bacteria residing in the human large intestine, although humans primarily rely on dietary sources for absorption in the small intestine.

Vitamin K is essential for the synthesis of prothrombin and other clotting factors in the liver, which are necessary for blood coagulation. Deficiency of Vitamin K leads to delayed blood clotting and excessive bleeding from minor injuries.