B-Complex Vitamins Flashcards
6 B-complex deficiencies
- loss of appetite (anorexia)
- poor growth
- emaciation
- nervous disorders
- dermatitis
- anemia
B1 deficiency recognized by the chinese in 2600 bc
Beriberi
what year was thiamin synthesized
1936
thiamin’s principle role
part of the coenzyme cocarboxylase
TTP is the coenzyme for how many enzyme systems
at least 24
in the absence of ____ decarboxylation reactions don’t occur at normal rate and pyruvuc acid & lactic acid accumulate in blood and tissues
thiamin
6 deficiency symptoms of thiamin
- Beriberi in man
- polyneuritis
- soft muscles
- anorexia/loss of appetite
- weight loss
- bradycardia - lowered heart rate
characterized by extensive damage to nervous and cardiovascular systems. Accompanied by severe muscle wasting (___ beriberi) or edema (___ berberi).
Berberi
- dry beriberi
- wet beriberi
represents final stages of thiamin deficiency that is a result of or associated with:
1) accumulation of intermediates of CHO metabolism
2) peripheral nerve degeneration
polyneuritis
2 principle factors influencing B1 requirements
- carb intake
2. calorie intake
true or false. B1 deficiency principally seen with chronic alcoholism
true
thiamin is destroyed by what in the presence of moisture
heat
thiamin is phosphorylated to TTP in what organ
liver
what animal can store a 2 month supply of thiamin in its tissues
pig
what allows ruminants to synthesize enough B1 from bacteria
a functional rumen
what animal can synthesize B1 in the cecum and large intestine but still needs dietary intake
horse
2 antivitamins of B1
pyrithiamine and thiaminase
sources of B1 (thiamin)
plants (mainly) yeast mold leaves of grasses germ of cereal grains seed coats of grains pork has 100x more than beef
higher plants, yeast, fungi, and some bacteria make ____
B2 (riboflavin)
the 2 coenzymes of riboflavin
- FMN - flavin mononucleotide - 1 phosphate group
2. FAD - flavin adenine dinucleotide - 2 phosphate groups
plays an essential role in release of food energy and assimilation of nutrients
riboflavin
6 riboflavin deficiencies
- decreased growth
- alopecia or hair loss in rats
- opaque cornea or cataracts in humans
- curled tow paralysis in chicks (walk on hocks & toes curled inwards)
- low egg production & hatchability
- skin & eye symptoms in man
roughened skin and furrows around the mouth
cheilosis
due to over activity of sebaceous or oil glands; results in waxy dermatitis of eyes, ear lobes, and mouth
dermatitis
increased blood vessels in eye
corneal vascularization
where is riboflavin phosphorylated
intestinal wall
sources of riboflavin
higher plants yeast (richest source) - and milk fungi some bacteria ruminants eggs liver kidney muscle whey & distillers solubles
when pyridoxine was first synthesized
1939 - Harris & Folker
two forms of pyridoxine discovered what year
1945
two forms of pyridoxine
pyridoxal
pyridoxamine
results in substantial loss of pyridoxine
sterilization of milk products
active forms of pyridoxine
pyridoxal phosphate (more active one) pyridoxamine phosphate
after absorbed the forms of pyridoxine are phosphorylated where
liver
pyridoxal phosphate serves as coenzyme for enzyme systems concerned with ____ metabolism
protein (amino acid metabolism)
process that provides for synthesis of non-essential amino acids & important system in animal tissues
transamination
pyridoxal phosphate serves as coenzyme in what process that decarboxylates several amino acids
decarboxylation
pyridoxal phosphate involved of synthesis of _____ from the amino acid _____.
niacin; tryptophan
true or false: pyridoxal phosphate influences intestinal transport and tissue uptake of amino acids.
true
2 antivitamins of pyridoxine
desoxypyridoxine and isoniazid
5 pyridoxine (B6) deficiencies
- growth failure and acrodynia
- urinary calcui - cattle
- anemia - dogs, pigs, rats
- convulsions or epileptic seizures
- slow growth and suppressed appetite
characterized by dermatitis of tails, ears, mouth, and paws that’s accompanied by edema
acrodynia
sources of pyridoxine
yeast liver muscle meat milk cereal grains
b-complex are ___ soluble vitamins produced in the cecum and large intestine of the horse.
water
are B-vitamins dietary essentials for ruminants only? Horses? Cats?
ruminants only - No
horses - Yes
cats - Yes
What vitamin is known to have a higher requirement in high protein diets because of its involvement in protein metabolism?
B6
There is essentially no storage of the B-complex vitamins; therefore, a daily intake is essential. The pig is an exception, however, with regard to one of the B-vitamins in that a two month supply is stored in the tissues. What is this vitamin?
thiamin
