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9.3.2 Water Soluble Vitamins
9.3.2.1 Thiamine (Vitamin B1)
Thiamine or vitamin B1 is water-soluble and acts as coenzyme known thiamine
pyrophosphate. Thiamine pyrophosphate is involved in carbohydrate metabolism.
Thiamine pyrophosphate is also involved in the hexose monophosphate shunt. It is
a neuro-protective agent (Ikeda et al. 2016). Thiamine is found in nuts, potatoes,
meat, beans, and cereals. Its deficiency leads to a disease known as beriberi. It is
often observed in polished rice-eating communities because, in polished rice, the
seed coat, which contains this vitamin, is removed. There are three types of beriberi:
dry, wet and infantile (Romagnoli et al. 2012). Thiamine is a co-catalyst in sugar
digestion and is necessary to the function of the heart, nerves, and muscles. Vitamin
B1 sources include unmilled oat, wheat germ, beets, nuts, meat, lentils, potatoes,
pork, eggs, poultry, dried beans, green peas, beans, green verdant vegetables.
Thiamine insufficiency can cause beriberi, polyneuritis, mental disarray, ataxia or
Wernicke-Korsakoff syndrome in alcoholics. Excess can lead to tachycardia,
migraines or peevishness, a sleeping disorder (Wiley and Gupta 2019).
9.3.2.2 Riboflavin (Vitamin B2)
Riboflavin (or lactoflavin) is a yellow crystalline substance. Riboflavin is found in
grain, milk, eggs, liver, oats, and green verdant vegetables. It is involved in tissue
respiration. Its derivatives are FAD (flavin adenine dinucleotide in its oxidized state)
and FADH 2 (FAD in its reduced form). FADH 2 gives two ATP in the electron transport chain. FAD and FADH 2 are involved in oxidation-reduction reactions. One
FADH 2 is obtained in the TCA cycle (Barile et al. 2016). These act as coenzymes in
the alpha-keto glutarate dehydrogenase and succinate dehydrogenase complexes.
Its deficiency results in a condition known as ariboflavinosis. Ariboflavinosis is
characterized by cheilosis (textured desquamation of the skin around the mouth),
glossitis (sparkly red and sore tongue), soreness of the lips, eye disturbances and
photophobia (light sensibility), oily skin the nose, scrotal dermatitis (Henriques
et al. 2010).
9.3.2.3 Niacin (Vitamin B3)
It is a water-soluble vitamin essential to the human diet, but can be synthesized in
the body from tryptophan. Its deficiency leads to a condition known as pellagra. It
is found in some cereals, yeast extracts, and meat. In the body, niacin is converted
to the NAD (nicotinamide adenine dinucleotide) coenzyme. These co-enzymes are
involved in oxidation-reduction reactions. They act as coenzymes of the isocitrate
9 Vitamins and Minerals: Types, Sources and their Functions
9.3.2 Water Soluble Vitamins
9.3.2.1 Thiamine (Vitamin B1)
Thiamine or vitamin B1 is water-soluble and acts as coenzyme known thiamine
pyrophosphate. Thiamine pyrophosphate is involved in carbohydrate metabolism.
Thiamine pyrophosphate is also involved in the hexose monophosphate shunt. It is
a neuro-protective agent (Ikeda et al. 2016). Thiamine is found in nuts, potatoes,
meat, beans, and cereals. Its deficiency leads to a disease known as beriberi. It is
often observed in polished rice-eating communities because, in polished rice, the
seed coat, which contains this vitamin, is removed. There are three types of beriberi:
dry, wet and infantile (Romagnoli et al. 2012). Thiamine is a co-catalyst in sugar
digestion and is necessary to the function of the heart, nerves, and muscles. Vitamin
B1 sources include unmilled oat, wheat germ, beets, nuts, meat, lentils, potatoes,
pork, eggs, poultry, dried beans, green peas, beans, green verdant vegetables.
Thiamine insufficiency can cause beriberi, polyneuritis, mental disarray, ataxia or
Wernicke-Korsakoff syndrome in alcoholics. Excess can lead to tachycardia,
migraines or peevishness, a sleeping disorder (Wiley and Gupta 2019).
9.3.2.2 Riboflavin (Vitamin B2)
Riboflavin (or lactoflavin) is a yellow crystalline substance. Riboflavin is found in
grain, milk, eggs, liver, oats, and green verdant vegetables. It is involved in tissue
respiration. Its derivatives are FAD (flavin adenine dinucleotide in its oxidized state)
and FADH 2 (FAD in its reduced form). FADH 2 gives two ATP in the electron transport chain. FAD and FADH 2 are involved in oxidation-reduction reactions. One
FADH 2 is obtained in the TCA cycle (Barile et al. 2016). These act as coenzymes in
the alpha-keto glutarate dehydrogenase and succinate dehydrogenase complexes.
Its deficiency results in a condition known as ariboflavinosis. Ariboflavinosis is
characterized by cheilosis (textured desquamation of the skin around the mouth),
glossitis (sparkly red and sore tongue), soreness of the lips, eye disturbances and
photophobia (light sensibility), oily skin the nose, scrotal dermatitis (Henriques
et al. 2010).
9.3.2.3 Niacin (Vitamin B3)
It is a water-soluble vitamin essential to the human diet, but can be synthesized in
the body from tryptophan. Its deficiency leads to a condition known as pellagra. It
is found in some cereals, yeast extracts, and meat. In the body, niacin is converted
to the NAD (nicotinamide adenine dinucleotide) coenzyme. These co-enzymes are
involved in oxidation-reduction reactions. They act as coenzymes of the isocitrate
9 Vitamins and Minerals: Types, Sources and their Functions