Water soluble vitamins Flashcards
What are vitamins?
Vital amines
Grouped according to function
Water soluble vs fat soluble
Essential - must be consumed in diet
Water soluble vitamins
Vitamin C
B group Vitamins:
- Thiamin
- Riboflavin
- Nicotinamide
- Pyridoxine
- Pantotheric acid
- Biotin
- Folic acid
- Choline
- Cyanocobalamin
Fat soluble vitamins
Vitamin A (retinol)
Vitamin D2 (ergocalciferol)
Vitamin D3 (cholecalciferol)
Vitamin E (tocopherol)
Vitamin K (phylloquin one)
Vitamin C deficiency
Anaemia, exhaustion, spontaneous bleeding, swelling of the limbs, particular rash, ulceration of the gums, loss of teeth, reduced rate of wound healing
Can be fatal
Easily treated with oral or intravenous vitamin C
Vitamin C
Colourless, crystallin water soluble compound
Acidic and strong reducing properties
Heat stable in acid solution
Strongly decomposed in alkaline conditions
Destroyed by exposure to light
Large amounts in citrus fruits, green leafy vegetables, some berries
Synthetic ascorbic acid readily available commercially
Role in many oxidation-reduction mechanisms in living cells
Important role in collagen metabolism
Role in iron metabolism
Antioxidant – in conjunction with vitamin E protect against free radicals
A dietary essential compound ONLY for: Humans Primates Guinea pig Red vented bul bul bird and fruit eating bats (and apparently some fish)
B group vitamins
All water soluble
Not stored in the tissues in appreciable amounts
Most are components of coenyzmes
Deficiency causes vague poor growth symptoms ‘ill thrift’
Thiamin (B1)
Very water soluble
Fairly stable in mildly acidic solutions
Decomposes quickly in neutral solution
Widely distributed in foods
Outer layer of seeds and the growing areas of roots, shots and leaves
Large amounts in fermentation products
Animal products – egg yolk, liver, kidney, pork meat
Thiamin (B1) deficiency - Most species
Loss of appetite, emaciation muscular weakness, dysfunction of the nervous system
Thiamin (B1) deficiency - Pigs
Loss of appetite, growth, vomiting
Thiamin (B1) deficiency - Chicks
Poor appetite, emaciated, polyneuritis
Thiamin (B1) deficiency - Ruminants
Bacterial synthesis in rumen (but may be affected by thiaminase) can lead to cerebrocorticol necrosis (CCN)
Riboflavin (B vitamin)
Yellowish crystalline substance – fluoresces in aqueous solution
Destroyed by alkali
Unstable in light
Occurs in all biological materials
Can be synthesised by green plants, yeasts, fungi and some bacteria
Good sources - yeast, liver, milk, green leafy crops
Cereal grains are POOR source
Riboflavin deficiency - Ruminants
Unlikely if have rumen (synthesised there) but in young calves and lambs loss of appetite, diarrhoea and lesions in mouth corners
Riboflavin deficiency - Pigs
Poor appetite, vomiting, skin and eye abnormalities (prevents premature birth in sows)
Riboflavin deficiency - Chicks
Poor growth, curled toe paralysis, reduced hatchability, ‘clubbed down’
Nicotinamide (B vitamin)
Stable, not easily destroyed by heat, acids, alkali or oxidation
Can be synthesised from tryptophan in the body but efficiency of conversion is poor
Cats do not need to produce as natural diet is well supplied
Rich sources – liver, yeast, groundnut and sunflower meals
Milk and eggs contain the precursor tryptophan
Cereal grains poor source as the vitamin in present in a bound form
Nicotinamide deficiency - Pigs
Poor growth, anorexia, vomiting, dermatitis
Nicotinamide deficiency - fowls
Bone disorders, feathering abnormalities, mouth inflammation
Vitamin B6
Exists in three intraconvertible forms (pyridoxine, pyridoxal, pyridoxamine)
Present in plants as pyridoxine
Animal products may also contain pyridoxal and pryidoamine
Widely distributed in yeast, pulses, cereal grains, liver and milk
Coenzyme function
Vitamin B6 deficiency - Pigs
Reduce food intake and develop anaemia
Vitamin B6 deficiency - Chicks
Develop jerky movements
Folic acid
Widely distributed in nature, green leafy vegetables, cereals and extracted oilseed meals are rich sources
Reasonably stable in storage when dry
Readily degraded by moisture, high temperatures, ultraviolet light
A certain type of anaemia could be cured in humans by treatment with yeast or liver extracts
Folic acid deficiency - Chicks and young turkeys
Poor growth, anaemia, poor bone development, poor egg hatchability
Biotin
Widely distributed in foods
Rich in liver, milk, yeast, oilseeds and vegetables
Bioavailability can be low due to binding (barley and wheat) in chicks and pigs
Bioavailability high in maize and oilseeds
Involved in metabolism
Biotin deficiency - Pigs
Foot lesions, hair loss, dry scaly skin – in growers growth rate decreased and in sows reduced reproductive performance
Biotin deficiency - Poultry
Reduced growth, dermatitis, leg bone abnormalities, cracked feet, fatty liver and kidney syndrome
Biotin deficiency - Ruminants and horses
Not dietary essential but can improve hoof health
Biotin deficiency
Can be induced by feeding raw egg whites (avidin)
Avidin combines with the vitamin and prevents absorption
Certain Streptomyces spp bacteria present in soil and manure produce compounds that have the same action
Heating inactivates these antagonist proteins
B12
The most complex of all the vitamins
Ring structure with a cobalt atom in the centre
Cyano group attached to the cobalt
Acts as coenzyme in metabolism
Considered to be synthesised exclusively by microorganisms
Animal origin only
