vitamins b group vitamin b 1 (thiamine)thiamine vitamin b 2 (riboflavin)riboflavin vitamin b 3 or...

Vitamins B groupVitamins B group

Vitamin B1 (Thiamine)

Vitamin B2 (Riboflavin)

Vitamin B3 or Vitamin P or Vitamin PP (Niacin)

Vitamin B5 (Pantothenic acid)

Vitamin B6 (Pyridoxine and Pyridoxamine)

Vitamin B7 or Vitamin H (Biotin)

Vitamin B9 or Vitamin M and Vitamin B-c (Folic acid)

Vitamin B12 (Cyanocobalamin)

Vitamin B1 (Thiamine)

Composed of a substituted pyridine and thiazole ring.

Thiamine (vitamin B1) was the first of the water-soluble B-vitamin family to be discovered.

Natural Sources

Thiamine are found in many nuts, seeds, brown rice, seafood, and whole-grain products (Grains are stripped of the B vitamin content during processing).

Sunflower seeds are a particularly good source.

Legumes, milk, and beef liver.

StabilityStability Thiamine is destroyed by prolonged heat. Food should be cooked in small amounts of water so that

thiamine and other water-soluble vitamins don't leach out. Baking soda should not be added to vegetables as it breaks

Vitamin B1. Avoid sulfite preservatives as it breaks Vitamin B1. Drinking tea with a meal will also drastically decrease the

amount of thiamine that is absorbed by the body. Vitamin B1 is stable in acid, unstable in aqueous solutions

of PH more than 5. It is readily oxidized by exposure to the atmospheric

oxygen or by oxidizing agents to thiochrome. (blue fluorescence), used for the quantitative fluoremetric assay

Role of ThiamineRole of Thiamine It is an Co-factor for carbohydrates metabolism

(Kreb’s Cycle). This role enable conversion of blood sugar (glucose) into biological energy. This is important for: Provide energy to the brain. Improve transmission of nerve impulses through the nerves

by providing them with energy. Proper function of the heart muscles. Healthy mucus membrane. Maintenance of smooth and skeletal muscles. Formation of RBC’s.

In mammalian cells:In mammalian cells: Thiamine HCl is converted to Thiamine Pyrophosphate Co-Thiamine HCl is converted to Thiamine Pyrophosphate Co-

factor using ATP.factor using ATP. Thiamine pyrophosphate (TPP) is a coenzyme for:

pyruvate dehydrogenase. α-ketoglutarate dehydrogenase.

These enzymes function in the metabolism of carbohydrates. Transketolase. Transketolase functions in:

The pentose phosphate pathway to synthesize NADPH.

The pentose sugars deoxyribose and ribose involved in nucleic acids biosynthesis.

Required Daily AmountRequired Daily Amount

The daily requirements are based on the The daily requirements are based on the number of calories in diet. number of calories in diet.

It is about 0.5 mg/1000 calories.It is about 0.5 mg/1000 calories.

Average 1.5 mg/ day for 3000 calories.Average 1.5 mg/ day for 3000 calories.

Daily requirement increase with high Daily requirement increase with high carbohydrate intake and for hard worker or carbohydrate intake and for hard worker or athletes.athletes.

Structure Activity Relationship (SAR)Essential features for activity:

Methylene bridge.Amino group in the pyrimidine ring.Hydroxy ethyl group at the thiazole ring.Methyl group of pyrimidine ring, when replaced by:

a- Ethyl or propyl groups gives an active compound. b- Butyl group gives inactive compound.

N

N

N

NH2 S

Me

Me

CH2CH2OH

Vitamin antagonists Oxythiamine is a competitive inhibitor. Neopyrithiamine prevent phosphorelation of

hydroxy ethyl group that is essential for activity of the vitamin.

Thiaminase in raw fish destroy vitamin B1

N

N

N

OH S

Me

Me

CH2CH2OH N

N

N

NH2Me

CH2CH2OH

Oxythiamine

Me

Pyridine Ring

Neopyrithiamine

Causes of DeficiencyA lack of thiamine can be caused by:

Malnutrition. A diet high in thiaminase-rich foods (raw freshwater fish, raw shellfish, ferns)Foods high in anti-thiamine factors (tea, coffee, nuts).Chronic consumption of alcohol.

Diagnostic Testing for B1 Deficiency

A diagnosis test for B1 deficiency can be determined by measuring transketolase levels of erythrocyte

DeficiencyBeriberi: The syndrome typically causes poor appetite, abdominal pain, heart enlargement, constipation, weakness, swelling of limbs, muscle spasms, insomnia, and memory loss (all reversed on treatment). Wernicke-Korsakoff syndrome: Resulted from untreated Beriberi and characterized by confusion, disorientation, inability to speak, numbness or tingling of extremities, edema, nausea, vomiting, visual difficulties, and may progress to psychosis, coma, and death. Even in advanced states, this condition can be reversible if B1 is given.

Risk Factors for DeficiencyThe leading risk factor for thiamine deficiency is alcoholism. Alcohol acts directly to destroy thiamine and increases it’s excretion.

Liver cirrhosis, malabsorption syndromes, diabetes, kidney disease, or hypermetabolic conditions also have increased susceptibility to B1 deficiency.

The elderly peoples with poor nutritional status and difficulties with absorption.

Others with nutritionally inadequate diets, or an increased need as a result of stress, illness, or surgery may benefit from additional vitamin B1 intake.

Use of tobacco products, or carbonate and citrate food additives can impair thiamine absorption.

Side Effects

In very unusual, large doses of thiamine may cause rashes, itching, or swelling. These reactions are more common with intravenous injections than oral supplements.

InteractionsOral contraceptives, antibiotics, sulfa drugs, and certain types of diuretics may lower thiamine levels in the body.

Taking this vitamin may also intensify the effects of neuromuscular blocking agents that are used during some surgical procedures.

B vitamins are best absorbed as a complex, and magnesium also promotes the absorption of thiamine

Vitamin B2Riboflavin, lactoflavin, Vitamin G

N

N

NH

NMe

Me

O

O

CH2OH

(HO-C-H)3

CH2

Ribose moiety

Vit B2 = Riboflavin

Isoalloxazine moiety

It chemically has a three rings structure (isoalloxazine) linked to ribityl moiety. Riboflavin is a yellow to orange- yellow powder, soluble in water (1:3000 to 1:20000) due to internal crystalline structure, urea or niacinamide are used to solubilize riboflavin when high concentrated solution needed.

Natural SourcesNatural Sources Milk, cheese, egg white and liver. leafy green vegetables, almonds and mature soybeans Yeast.

Other sources:

Added as food colouring Fortify some foods as baby foods, breakfast cereals,

sauces, processed cheese, fruit drinks and vitamin-enriched milk).

Required Daily AmountRequired Daily Amount 1.3- 1.6 mg/day.1.3- 1.6 mg/day.

StabilityStabilityVitamin B2 is unstable to light in both acidic

and basic medium. Under acidic condition light produce

lumichrome. In alkaline PH light produce lumiflavin.

Both are inactive biologically.

N

N

NH

NMe

Me

O

O

CH2OH

(HO-C-H)3

CH2

Vit B2 = Riboflavin

N

N

NH

NMe

Me

O

O

CH3

N

N

NH

HN

Me

Me

O

O

Lumiflavine Lumichrome

Light in (H) medium

Light (OH) medium

Role of Vitamin BRole of Vitamin B22

Riboflavin is converted to the active forms:Riboflavin is converted to the active forms: Riboflavin-Mononucleotide more correct Riboflavin-Riboflavin-Mononucleotide more correct Riboflavin-

Monophosphate (FMN).Monophosphate (FMN). Riboflavin-Adenine Dinucleotide more correct Riboflavin-Adenine Dinucleotide more correct

Riboflavin-Adenine Diphosphate (FAD).Riboflavin-Adenine Diphosphate (FAD).

The Active forms work as co-enzymes for about 150 The Active forms work as co-enzymes for about 150 oxidation-reduction reactions involved in:oxidation-reduction reactions involved in:

Carbohydrate, Proteins and fat metabolismCarbohydrate, Proteins and fat metabolism Activation of vitamin BActivation of vitamin B1212 and folate. and folate. Protection of erythrocytes and other cells from oxidative stress.Protection of erythrocytes and other cells from oxidative stress.

AbsorptionRiboflavin is absorbed in the proximal

intestine.

Riboflavin is stored mainly in the liver, kidney and heart in the form of FAD (70- 90%) or FMN or Riboflavin.

Causes of Riboflavin Deficiency

Not getting enough of the vitamin from the diet.

A result of conditions that affect absorption in the intestine.

The body not being able to use the vitamin.

An increase in the excretion of the vitamin from the body.

AriboflavinosisSymptoms of riboflavin deficiency: Cracked and red lips. Inflammation of the lining of mouth and tongue. Mouth ulcers, angular cheilitis. Dry and scaling skin and iron-deficiency anemia. The eyes become bloodshot, itchy and sensitive to bright light.

Angular cheilitis: is an inflammatory lesion at the corner of the mouth. Usually associated with a fungal (Candidal) or bacterial (Staphylococcal) infection The condition manifests as deep cracks or splits. In severe cases, the splits can bleed when the mouth is opened.

Diagnostic Testing of B2 Deficiency

A positive diagnostic test of serum riboflavin by measuring glutathione reductase levels of erythrocytes.

Risk Factors for Deficiency People under high stress, including those experiencing

surgery, chronic illnesses, liver disease, or poor nutritional status.

Diabetics have a tendency to be low on riboflavin as a result of increased urinary excretion.

Athletes, and anyone else with a high-energy output will need additional vitamin B2.

The elderly due to nutritional inadequacy as well as problems with absorption.

Smokers and alcoholics are at higher risk for deficiency as tobacco and alcohol suppress absorption.

Birth control pills may possibly reduce riboflavin levels, as can phenothiazine tranquilizers, tricyclic antidepressants, and probenecid.

Recent advances in human genetics indicate that certain genotypes are at greater risk for riboflavin deficiency than others.

UsesUses High doses of riboflavin(400 mg/day) have been

shown to reduce the frequency and severity of migraine headaches by half in susceptible people.

Riboflavin help decrease the incidence of cataracts.

Improve memory.

Riboflavin and vitamin C both help boost the body's level of glutathione which is an antioxidant.

Healthy development of the fetus.

Interactions

Probenecid (anti-gout) and propantheline bromide (anti-peptic ulcers) both delays and impairs absorption.

Phenothiazines (antipsychotic drugs) increase the excretion of riboflavin, thus lowering serum levels.

Oral contraceptives may also decrease serum levels. Tricyclic antidepressants may lower the levels of

riboflavin in the body. Absorption of riboflavin is improved when taken

together with other B vitamins and vitamin C. Riboflavin interferes with the absorption and

effectiveness of anti-malarial (ex. chloroquine), tetracycline antibiotics and sulfa-containing drugs.

AssayAssay

Direct fluoremetry.

Lumiflavin method in which riboflavin is irradiated in alkaline medium to yielded a chloroform-soluble lumiflavin, measured fluoremetry. It is preferred in biological samples.

Vitamin B3

(Niacin, Nicotinic acid, Nicotinamide,Vitamin P, Vitamin PP))

N

COOH

N

CONH2

Nicotinic acid Nicotinamide

Natural SourcesNatural Sources

Tuna is one of the best sources of niacin.

Most processed grain products are fortified with niacin.

Cottage cheese, milk are highest in Tryptophan and about half of the Tryptophan consumed is used to make niacin.


About 7 mg/ 1000 calories.About 7 mg/ 1000 calories.

13- 20 mg/day.13- 20 mg/day.


It is act as co-enzyme in oxidation-reduction It is act as co-enzyme in oxidation-reduction reactions:reactions:

Catabolic reactions:Catabolic reactions:NADNAD++/NADH/NADH

Anabolic reactions:Anabolic reactions:NADPNADP++/NADPH/NADPH

PharmacokineticsPharmacokinetics Absorption:Absorption:

At low concentration by active transportation.At low concentration by active transportation. At high concentration by passive diffusion.At high concentration by passive diffusion.

Transportation:Transportation: Both Nicotinic acid (NA) AND Nicotinamide (NAm) Both Nicotinic acid (NA) AND Nicotinamide (NAm)

bind to plasma proteins for transportation.bind to plasma proteins for transportation. Biosynthesis:Biosynthesis:

The liver can synthesize Niacin from the essential amino acid Tryptophan, but the synthesis is extremely slow and requires vitamin B6 (60 mg of Tryptophan= 1mg of niacin). Bacteria in the gut may also perform the conversion but are inefficient.


13- 20 mg/day13- 20 mg/day

DeficiencyDeficiency Pellagra: A serious deficiency of niacin. The

main results of pellagra can easily be remembered as "the four D's": diarrhea, dermatitis, dementia, and death. It is very rare now, except in alcoholics, strict vegetarians, and people in areas of the world with very poor nutrition.

Milder deficiencies of niacin can cause dermatitis around the mouth and rashes, fatigue, irritability, poor appetite, indigestion, diarrhea, headache.

Risk Factors for Deficiency Vegans, and others who do not eat animal protein,

should consider taking a balanced B vitamin supplement.

Others people under high stress, chronic illnesses, liver disease may need extra niacin and other B vitamins.

People over 55 years old are more likely to have a poor dietary intake.

Certain metabolic diseases also increase the requirement for niacin.

Those who abuse nicotine, alcohol or other drugs are very frequently deficient in B vitamins, but use of niacin with alcohol can cause seriously low blood pressure.

General Uses Niacin in very large doses (2-3 g/day) is used

to decrease blood cholesterol levels and reduce the risk of heart attack.

In certain conditions (gout, diabetes, peptic ulcer, liver or kidney disease, and high blood pressure).

Niacinamide used on a long-term basis to prevent the onset of juvenile diabetes (children).

Treatment of Pellagra.

Side Effects

In large amounts Niacin commonly causes flushing and headache. This can be avoided by taking it in the form of inositol hexaniacinate.

InteractionsInteractions Niacin with high blood pressure medication may cause

hypotension.

Isoniazid inhibits the body's ability to make Niacin from tryptophan. Extra niacin may be required.

Supplements may also be needed by women taking oral contraceptives.

Cholestyramine and cholestipol (medications to lower cholesterol) should be taken at a different time than Niacin or they will reduce its absorption.

Transdermal Nicotine used with Niacin is likely to cause flushing and dizziness.

Carbamazepine (an antiseizure medication) is more likely to cause toxicity in combination with niacin.

Nicotinic acid reacts with hemoglobin and myoglobin in meat to form a brightly coloured complex, and thus has been used as a food additive, typically to improve the colour of ground meat.

Concomitant use of Niacin with Statin class drugs to lower cholesterol can cause myopathy.

Vitamin BVitamin B55

(Pantothenic acid)(Pantothenic acid) It is a peptide substance composed of Pantoic acid and -

Alanine. It can be present as the Calcium salt or the Alcohol

“Pantothenol”.

HO CH2 C CH NH CH2

CH3

CH3

OH

CH2 COOHC

O

HO CH2 C CH NH CH2

CH3

CH3

OH

CH2 CH2OHC

O

-AlaninePantoic acid

Pantothenic Acid

Pantothenol


Animal Sources:Animal Sources: Liver, kidney and Heart.Liver, kidney and Heart. Milk and Milk Products (Cheese, Yogurt and Butter).Milk and Milk Products (Cheese, Yogurt and Butter).

Plant Sources:Plant Sources: CerealsCereals

Honey and Molasses.Honey and Molasses. Yeasts.Yeasts.


It is a part of Co-enzyme A that assists the It is a part of Co-enzyme A that assists the following reactions:following reactions:

Formation of Sterols (Cholesterol and 7-Formation of Sterols (Cholesterol and 7-Dehydrocholesterol).Dehydrocholesterol).

Formation of Fatty acids.Formation of Fatty acids.

Formation of Keto acids such as Pyruvic acid.Formation of Keto acids such as Pyruvic acid.


4 Years and over 10 mg4 Years and over 10 mg Less than 4 years 5 mgLess than 4 years 5 mg Infants 3 mgInfants 3 mg

DeficiencyDeficiency Rare to occur.Rare to occur. When occur it leads to Paresthesias When occur it leads to Paresthesias (is a (is a sensationsensation

of tingling, pricking, or numbness of a of tingling, pricking, or numbness of a personperson's 's skinskin).).

UsesUses:: Treat and prevent deficiency state.Treat and prevent deficiency state. Supplements in cases of inadequate diet.Supplements in cases of inadequate diet. It is Described for:It is Described for:

Diabetic neuropathy.Diabetic neuropathy. Arthritis.Arthritis. In hair dyes.In hair dyes.

Uses of DexpantothenolUses of Dexpantothenol

Topically for:Topically for: BurningBurning ItchingItching IrritationIrritation

To Relive gas retention.To Relive gas retention.

Vitamin B6

Pyridoxine

N

CH2OH

CH2OHHO

H3C

Pyridoxol

N

CHO

CH2OHHO

H3C

Pyridoxal

N

CH2NH2

CH2OHHO

H3C

Pyridoxine

N

COOH

CH2OHHO

H3C

Pyridoxic Acid


Vitamin BVitamin B66 is found in: Cereals, Beans, Meat, Liver, Fish, Yeast, Nuts and some fruits as Banana and Potatoes.

It is also produced by bacterial flora in the colon.


Vitamin B6 is needed for more than 100 enzymes involved in protein metabolism.

It is also essential for red blood cell metabolism and hemoglobin formation.

The nervous and immune systems need vitamin B6 to function efficiently.

It is also needed for the conversion of Tryptophan (an amino acid) to Niacin (Vitamin B3).

Vitamin B6 also helps maintain blood glucose within a normal range. When caloric intake is low vitamin B6 help to convert stored carbohydrate or other nutrients to glucose to maintain normal blood sugar levels.

Required Daily AmountRequired Daily Amount Babies under six months 0.3 mgBabies under six months 0.3 mg Babies Six months to one year old 0.6 mg. Babies Six months to one year old 0.6 mg. Children 1- 3 years old 1.0 mg Children 1- 3 years old 1.0 mg 4- 6 years old 1.1 mg 4- 6 years old 1.1 mg 7- 10 years old 1.4 mg7- 10 years old 1.4 mg Males aged 11-14 years 1.7 mgMales aged 11-14 years 1.7 mg 15 years and older 2.0 mg15 years and older 2.0 mg Females 11-14 years 1.4 mgFemales 11-14 years 1.4 mg Female 15- 18 years 1.5 mgFemale 15- 18 years 1.5 mg Women age 19 years and older 1.6 mgWomen age 19 years and older 1.6 mg Pregnancy 2.2 mg Pregnancy 2.2 mg Lactation (2.1 mg).Lactation (2.1 mg). Adults 1.4- 2.2 mg Adults 1.4- 2.2 mg

Causes of DeficiencyCauses of Deficiency Individuals with a poor quality diet or an

inadequate B6 intake.

Alcoholics because alcohol also promotes the destruction and loss of vitamin B6 from the body.

Older people.

Asthmatic children treated with theophylline because it decreases body stores of vitamin B6.

DeficiencyDeficiencySigns of vitamin B6 deficiency include:

Skin: Dermatitis (skin inflammation), Stomatitis (inflammation of the mucous lining of any of the structures in the mouth), Glossitis (is inflammation or infection of the tongue ).

Neurological abnormalities: Depression, confusion, and convulsions.

Vitamin B6 deficiency also can cause anemia.

UsesUses Treatment and Prevention of deficiency.Treatment and Prevention of deficiency. For people are high risk of deficiency.For people are high risk of deficiency. Can also described in:Can also described in:

AcneAcne Kidney stonesKidney stones Premenstrual syndromesPremenstrual syndromes Improve some CNS conditions.Improve some CNS conditions.

Side EffectsSide Effects Too much vitamin B6 can result in nerve

damage to the arms and legs. This neuropathy is usually related to high intake of vitamin B6 and is reversible when supplementation is stopped.

InteractionInteraction Some Drugs increase the excretion of Some Drugs increase the excretion of

Vitamin BVitamin B66 by the body as: by the body as:

Chloramphenicol.Chloramphenicol.Oral Contraceptives.Oral Contraceptives.Cycloserine.Cycloserine.Isoniazide.Isoniazide.L-DopaL-Dopa

Vitamin BVitamin B77((Vitamin H, Biotin, Growth Factor, Co-enzyme R)

It is 2-Imidazolidinone tetrahydrothiophene-4-valeric It is 2-Imidazolidinone tetrahydrothiophene-4-valeric acid.acid.

NH

HN

S

H

HH

(CH2)4-COOH

O


Liver.Liver. Meat.Meat. KidneyKidney YeastYeast Egg yolkEgg yolk MushroomsMushrooms Milk and milk products.Milk and milk products.


It is a co-enzyme for several carboxylation It is a co-enzyme for several carboxylation reactions.reactions.

Important for carbon dioxide fixation.Important for carbon dioxide fixation. Important for Carbohydrates and Fats Important for Carbohydrates and Fats

metabolism.metabolism. Co-factor for Pyruvate carboxylase.Co-factor for Pyruvate carboxylase.

Required Daily AmountRequired Daily Amount 100- 200 100- 200 g/day.g/day.

DeficiencyDeficiencyOnly induced in experimental animals not observed in Only induced in experimental animals not observed in

human:human: Skin lesionsSkin lesions Retarded growthRetarded growth Hair lossHair loss

Biotin AntagonistsBiotin Antagonists

Structural analogs:Structural analogs: Biotin sulfonateBiotin sulfonate DesthiobiotinDesthiobiotin Imidazolidone acids.Imidazolidone acids.

Avidin in Raw egg combines and inactivate Avidin in Raw egg combines and inactivate Biotin.Biotin.

UsesUses

Treat and prevent deficiency conditions.Treat and prevent deficiency conditions. Supplement in cases of inadequate diet.Supplement in cases of inadequate diet. In vitamin B-Complex to improve glucose In vitamin B-Complex to improve glucose

metabolism.metabolism. In skin disease as Acne and Dermatitis.In skin disease as Acne and Dermatitis.

Vitamin BVitamin B99

((Vitamin M, Vitamin B-c, Folic acid ) Conjugate of Pteridine, Conjugate of Pteridine, pp-Aminobenzoic acid and -Aminobenzoic acid and

Glutamic acid.Glutamic acid.

N

N

N

N

CH2 NH C NH CH

COOH

CH2

CH2

COOH

OH

H2N

O

Pteridine

p-Aminobenzoic acid Glutamic acid


Liver.Liver. YeastYeast FruitsFruits Leafy VegetablesLeafy Vegetables Milk and milk products.Milk and milk products.


Folic Acid Dihydrofolate (DHF)

Tetrahydrofolate (THF)

Folic acid

reductase

Dihydrofolic acid

reductase

THF act as Co-enzyme for:THF act as Co-enzyme for: Leucopoiesis (Production of Leukocytes).Leucopoiesis (Production of Leukocytes). Erythropoiesis (Production of Erythrocytes).Erythropoiesis (Production of Erythrocytes). Nucleoprotein synthesis.Nucleoprotein synthesis.

Required Daily AmountRequired Daily Amount 0.1- 0.8 mg/day.0.1- 0.8 mg/day.

DeficiencyDeficiencyVery rare due to:Very rare due to: Malabsorption (due to alcoholism).Malabsorption (due to alcoholism). Impaired Hepatic functions (due to alcoholism).Impaired Hepatic functions (due to alcoholism).

Leads to:Leads to: Glossitis (is inflammation or infection of the tongue ). Megaloblastic anemia Leucopenia

Biotin AntagonistsBiotin Antagonists

Structural analogs:Structural analogs: Sulfonamides.Sulfonamides.

UsesUses

Treat and prevent deficiency conditions.Treat and prevent deficiency conditions. Supplement in cases of inadequate diet.Supplement in cases of inadequate diet. Treatment of chronic intestinal and liver Treatment of chronic intestinal and liver

diseases.diseases.

B vitamins Deficiency

Vitamin B1 (Thiamine) deficiency causes Beriberi. Symptoms

of this disease of the nervous system include weight loss, emotional disturbances, Wernicke's encephalopathy (impaired sensory perception), weakness and pain in the limbs, periods of irregular heartbeat, and edema (swelling of bodily tissues). Heart failure and death may occur in advanced cases. Chronic thiamine deficiency can also cause Korsakoff's syndrome, an irreversible psychosis characterized by amnesia and confabulation.

Vitamin B2 (Riboflavin) deficiency causes Ariboflavinosis.

Symptoms may include cheilosis (cracks in the lips), high sensitivity to sunlight, angular cheilitis, glossitis (inflammation of the tongue), seborrheic dermatitis or pseudo-syphilis (particularly affecting the scrotum or labia majora and the mouth), pharyngitis, hyperemia, and edema of the pharyngeal and oral mucosa.

Vitamin B3 (Niacin) deficiency, along with a deficiency of tryptophan causes Pellagra. Symptoms include aggression, dermatitis, insomnia, weakness, mental confusion, and diarrhea. In advanced cases, pellagra may lead to dementia and death. Vitamin B5 (Pantothenic acid) deficiency can result in acne and Paresthesia, although it is uncommon. Vitamin B6 (Pyridoxine) deficiency may lead to anemia, depression, dermatitis, high blood pressure (hypertension) and elevated levels of homocysteine.

Vitamin B7 (Biotin) deficiency does not typically cause symptoms in adults but may lead to impaired growth and neurological disorders in infants. Vitamin B9 (Folic acid) deficiency results in elevated levels of homocysteine. Deficiency in pregnant women can lead to birth defects. Vitamin B12 (Cyanocobalamin) deficiency causes pernicious anemia, memory loss and other cognitive decline. It is most likely to occur among elderly people as absorption through the gut declines with age. In extreme (fortunately rare) cases paralysis can result.

Vitamin B12 (Cyanocobalamin, Antipernicious anemia factor)

StructureB12 is the most chemically complex of all the vitamins. The structure of B12 is based on a Corrin ring, similar to the Porphyrin ring found in Heme, Chlorophyll, and Cytochrome. The central metal ion is Co (cobalt). Four of the six coordinations od Co are provided by the Corrin ring nitrogens, and a fifth by a dimethylbenzimidazole group. The sixth coordination can be:

Cyano group (-CN) Cyanocobolamin

Hydroxyl group (-OH) Hydroxycobalamin

Methyl group (-CH3) Methylcobalamin (MeB12)

5'-deoxyadenosyl group Adenosylcobalamin (AdoB12).

Natural SourcesNatural Sources Bacteria such as Bacteria such as StreptomycinStreptomycin and and BacillusBacillus

present in the intestinal flora produce the vitamin present in the intestinal flora produce the vitamin required for man and animals.required for man and animals.

The vitamin is stored in the liver with estimated The vitamin is stored in the liver with estimated tt1/21/2 400 days. 400 days.

BB1212 can be obtained from animal products only can be obtained from animal products only

such as:such as: Liver and MeatLiver and Meat Fish and EggsFish and Eggs Milk and Dairy productsMilk and Dairy products

PharmacokineticsPharmacokinetics

Vitamin B12 in food is bound to the protein.

Hydrochloric acid in the stomach releases free vitamin B12.

Once released vitamin B12 combines with a substance called intrinsic factor (IF). This complex can then be absorbed by the intestinal tract.


Essential for the maturation of Erythrocytes. Protects against Pernicious anemia. Essential for cell growth and reproduction. Essential for the formation of myelin and

nucleoproteins.


Age (y)Males and

Females (μg/day)Pregnancy (μg/day)

Lactation (μg/day)

1-3 0.9 N/A N/A

4-8 1.2 N/A N/A

9-13 1.8 N/A N/A

14-18 2.4 2.6 2.8

19 and older 2.4 2.6 2.8

Causes of deficiencyCauses of deficiency

Inability to absorb vitamin B12 from food. Vegetarians who do not consume any

animals products. Stomach or intestinal disorder that limits

the absorption of vitamin B12. Inadequate production of intrinsic factor

(pernicious anemia). Competition for available B12 by parasites.

Symptoms of vitamin B12 deficiency

Pernicious Anemia: It is a type of Megaloblastic anemia characterized by decreased number of enlarged red blood cells.

Neurological changes such as numbness and tingling in the hands and feet.

Demyelination and irreversible nerve cell death.

Difficulty in maintaining balance, depression, confusion, dementia, poor memory.

In infants cause movement disorders and delayed development

UsesUses Treat and prevent deficiency conditions in Treat and prevent deficiency conditions in

combination with the intrinsic factor.combination with the intrinsic factor. Supplement in cases of inadequate diet or Supplement in cases of inadequate diet or

patient receiving antagonists.patient receiving antagonists. Radioactive BRadioactive B1212 to diagnose Pernicious anemia. to diagnose Pernicious anemia. In combination with Folic acid to treat In combination with Folic acid to treat

Megaloblastic anemia.Megaloblastic anemia. Large doses (5- 10 g IV) of Hydroxycobalamin

used in cyanide poisoning where it combine with cyanide ion to form harmless B12.

InteractionInteraction Some Drugs interfere with it absorption such as:

Alcohol, Aminosalicylic acid, Colchicine, Neomycin, Cholestyramine (Questran®), anticonvulsants (Phenytoin), the metformin (Glucophage®).

Vitamin C supplements can destroy dietary vitamin B12 and should be taken 2 hrs after meals.

H2 blockers include cimetidine, Proton pump inhibitors (PPIs) (omeprazole) reduce secretion of gastric acid and pepsin as a result reduce absorption of protein-bound (dietary) vitamin B12.

Vitamin CVitamin C((Ascorbic acid, Anti- Scurvy))

Vitamin C is a water-soluble vitamin. Almost all animals and plants synthesize

their own vitamin C. Vitamin C was first isolated in 1928 and in

1932 it was proved to be the agent which prevents scurvy.

ChemistryChemistry

Vitamin C is a weak acid, called Ascorbic acid or its salts “Ascorbate”.

It is the L-enantiomer of Ascorbic acid. The D-enantiomer shows no biological

activity. Commercial vitamin C is often a mix of

Ascorbic acid, Sodium ascorbate and/or other Ascorbates.

OO

OHHO

H

OH

HO

SourcesSources Vitamin C is obtained through the diet by

the vast majority of the world's population. The richest natural sources are fruits and vegetables.

Plant source Amount Plant source Amount Plant source AmountPlant

sourceAmount

plum 3150 Apricot 10 Papaya 60 Lettuce 4

Camu Camu 2800 Plum 10 Strawberry 60 Cucumber 3

Wolfberry 2500 Watermelon 10 Orange 50 Eggplant 2

Rose hip 2000 Banana 9 Lemon 40 Fig 2

Acerola 1600 Carrot 9 cantaloupe 40 Bilberry 1

Red pepper 190 Avocado 8 Cauliflower 40 Horned melon

0.5

Parsley 130 Crabapple 8 Grapefruit 30 Medlar 0.3

Guava 100 Peach 7 Papaya 60 Lettuce 4

Kiwifruit 90 Apple 6 Strawberry 60 Cucumber 3

Broccoli 90 Blackberry 6 Orange 50 Eggplant 2

Loganberry 80 Beetroot 5 Lemon 40 Fig 2

Redcurrant 80 Pear 4 cantaloupe 40 Spinach 30

Mandarin 30 Lime 20 Tomato 10 Mango 20

Chemical SynthesisChemical Synthesis

H

CHO

OH

HHO

OHH

OHH

CH2OH

HCH2OH

OHHHOOHHOHH

CH2OH

Reduction

SorbitolGlucose

H

CH2OH

OH

HHO

OHH

C=O

CH2OH

Sorbose

Acetobacter

Oxidation

CH2OH

OH

HOH2C

H

HO H

H HOO

CH2OH

OH

O H

H OO

CH2O

AcetoneKetal formation protection of O-dihydroxy

H

CH2OH

OH

HHOOHH

C=O

COOH

H

CH2OH

OH

HHOOH

C-OH

COOH

Oxidation

Hydrolysis

Enolization

Lactonization

OO

OHHO

H

OH

HO

StabilityStability

Ascorbic acid is reversibly oxidized to L- Dehydroascorbic acid on exposure to copper, heat and / or mild alkaline.

Both ascorbic and dehydroascorbic acids are physiologically active forms of vitamin C.

Further oxidation of L- Dehydroascrbic acid to 2,3-Diketo- gluconic acid and oxalate is irreversible.

Ascorbic acid is strong reducing agent, serves as an anti-oxidant and co-factor in hydroxylation reactions.


Adults: 60 mg/dayAdults: 60 mg/day Children: 30 mg/dayChildren: 30 mg/day

Role of Vitamin CRole of Vitamin C It is a cofactor in the synthesis of

norepinephrine from dopamine.

Vitamin C is also involved in a variety of metabolic processes including oxidation-reduction reactions and cellular respiration, carbohydrate metabolism, synthesis of lipids and proteins.

vitamin C are attributed primarily to antioxidant and free radical scavenging effects that maintain proper immune system.

T-lymphocyte activity, phagocyte function, leukocyte mobility, and possibly antibody and interferon production seem to be increased by vitamin C.

Involved in the synthesis of Collagen the major component of ligaments, tendons, cartilages and skin.

Involved in tyrosine metabolism.

Vitamin C deficiency Fatigue, personality changes, decline in psychomotor

performance and motivation.

Vitamin C deficiency over 3-5 months results in Symptomatic Scurvy:

In Adults: Scurvy leads to the formation of liver spots on the skin, spongy gums, and bleeding from all mucous membranes. The spots are most abundant on the thighs and legs, and a person with the ailment looks pale, feels depressed, and is partially immobilized. In advanced scurvy there are open, suppurating wounds and loss of teeth. Severe scurvy may progress to neuritis, jaundice, fever, dyspnea, and death.

In infants, symptoms: anorexia, irritability, growth retardation, thigh tenderness, pseudoparalysis, bleeding around the lower ends of the leg bones (femur and tibia) causing pain. If left untreated, scurvy can proceed to collagen deficiency, seizures, shock or sudden death.

It was common between Sailors, Pirates and others who were on ships that were out to sea longer than perishable fruits and vegetables could be stored.

Diagnosis of ScurvyDiagnosis of Scurvy Fasting blood ascorbic acid levels:

levels below 0.10 mg/dL are considered deficient. levels of 0.10-0.19 mg/dL are considered low. levels of 0.2 mg/dL or greater are acceptable levels greater than 0.6 mg/dL likely rule out scurvy.

White blood cell ascorbic acid concentration is considered a more accurate measurement of vitamin C nutritional status: with a level of zero suggesting scurvy. 0-7 mg/dL suggesting deficiency. 8-15 mg/dL considered low. 15 mg/dL or greater is adequate vitamin C status.

UsesUses Oral Vitamin C:Oral Vitamin C:

Preventing and treating scurvy. Preventing deficiency in people with gastrointestinal

diseases and those on chronic total parenteral nutrition or chronic hemodialysis.

Increasing iron absorption from the gastrointestinal tract.

Increasing the healing rate of wounds, burns, fractures, ulcers, and pressure sores.

Preventing and treating the common cold and other viral infections, bronchitis, human immunodeficiency virus (HIV) disease.

Topically Vitamin C is used for:

Improving skin conditions, protecting against free radicals and pollutants.

Improving photo-aged skin.

It is also applied topically for ulcerative mucositis associated with radiation therapy.

Parenterally Vitamin C is used for:

Preventing and treating vitamin C deficiency.

Correcting tyrosinemia in premature infants on high-protein diets.

Other Effects of Vitamin COther Effects of Vitamin C Decrease the risk of atherosclerosis and

peripheral arterial disease. decrease the risk of developing mouth cancer

and other cancers. Taking high doses of vitamin C orally might

decrease the duration of cold symptoms by doses of at least 2 g/day.

Taking vitamin C orally seems to decrease gastritis associated with acid suppressive therapy in patients with Helicobacter pylori infection.

Topical vitamin C can decrease the degree and duration of erythema.

Vitamin C orally along with antihypertensive medications appears to decrease systolic blood pressure, but not diastolic pressure.

Consuming vitamin C from dietary sources seems to lower blood concentrations of lead in cases of toxicity.

Reduce risk of Age-related mascular degeneration (AMD).

Side EffectsSide Effects Vitamin C is generally regarded as safe in amounts

obtained from foods side effects are rarely reported including nausea, vomiting, heartburn, abdominal cramps, and headache. Dental erosion may occur from chronically chewing vitamin C tablets.

High doses/toxicity: High doses of vitamin C greater than 2000 mg/day. These include kidney stones, severe diarrhea, nausea, and gastritis. Large doses may precipitate hemolysis in patients with glucose 6-phosphate dehydrogenase deficiency.

Vitamin C is metabolized to oxalic acid. Increased consumption increases the urinary concentration of oxalic acid and increases the risk of oxalate stone formation

Effect of Vitamin C on some DrugsEffect of Vitamin C on some Drugs Chromium: Vitamin C increases chromium

absorption.

Copper: High doses of vitamin C (1500 mg daily) can decrease serum levels of copper and the copper transport protein.

Grape: Patients with hypertension who take both vitamin C (500 mg/day) and grape seed polyphenols (1000 mg/day) have significantly increased systolic and diastolic blood pressure.

Vitamin B12: vitamin C can destroy dietary vitamin B12. Vitamin C supplements must be taken at least 2 hours after meals.

Acetaminophen (Tylenol): High doses of vitamin C (3 g) competitively inhibits sulfate conjugation of acetaminophen, increasing the half-life.

Aluminum: Vitamin C can increase the amount of (Al) absorbed. Patients with renal failure who take (Al) compounds chronically should avoid vitamin C in doses above the RDA.

Aspirin: Acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels .

Chemotherapy: Vitamin C (antioxidants) during chemotherapy could reduce the activity of chemotherapy drugs which generate free radicals.

Estrogens: Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy including topical products.

Warfarin (Coumadin): High doses of vitamin C may reduce the response to warfarin, possibly by causing diarrhea and reducing warfarin absorption.

Drugs affect Vitamin C levelDrugs affect Vitamin C level Aspirin increases elimination of vitamin C. It

reduces tissue and leukocyte uptake of vitamin C, leaving more in the plasma to be filtered into the urine.

Diuretics increases urinary losses of vitamin C, due to increased water excretion.

Estrogens can reduce vitamin C absorption or increase its breakdown.

Smokers have lower plasma levels of vitamin C than nonsmokers due to increased use of vitamin C to counteract free radicals in cigarette smoke.

DosesDoses

For scurvy, 100-250 mg once or twice daily.

For treating the common cold, 1-3 g daily.

During acute stress, vitamin C 1 g 3 times daily

For chronic hemodialysis in adults, 100-200 mg per day is recommended.

For preventing sunburn, 2 g of vitamin C and 1000 IU vitamin E has been used.

vitamins b group vitamin b 1 (thiamine)thiamine vitamin b 2 (riboflavin)riboflavin vitamin b 3 or...

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