Riboflavin(B2)

Question 1

INFO AND SOURCES —- rich & good

Answer 1

first of b complex to be isolated
synthesis by green plants and micro-organisms

Rich sources - liver,eggs,whole milk,dried yeast
Good sources - green leafy vegetables ,fish,whole cereals and legumes

riboflavin containing enzymes - flavoproteins
B2 is tightly bound to enzymes in tissues

Question 2

COENZYME ACTIVITY (FAD & FMN )

Answer 2

FAD :-
in oxdn process FAD→FADH2
2H -atomes are attached to N atoms in isoalloxazine nucleus
FMN :-
1) amino acid oxdn :- FMN→reduced→reoxidised by O2 →H2O2
2)respiratory chain :- NADH dehyrogenase contains it
NADH→FMN→CoQ

Question 3

ENZYMES REQUIRING FAD
—-8

Answer 3

1 FADH2 → 1.5ATP IN ETC
pyruvate dehydrogenase
methenyltetrahydrofolate reductase
xanthine oxidase
succinate dehyrogenase
α-ketoglutarate dehydrogenase
cytosolic retinal dehydrogenase
tryptophan to niacin
acyl-Coa-dehydrogenase

Question 4

DEFICIENCY MANIFESTATIONS
—-9

Answer 4

not seen normally bcs of it’s synthesis by intestinal flora
confines to skin and mucous membranes
glossitis
magenta coloured tongue
cheilosis
angular stomatitis
circumcorneal vascularisation
proliferation of bulbar conjuctival capillaries (earliest manifestation)
normochromic normocytic anemia ( bcs of interfernce in Fe absorption)
irregular ridges in nails
Rare inborn error of B2 transporter def. - motor ans sensory neuronal degradation

Question 5

RDA

Answer 5

adults - 2-3mg/day
pregnancy and lactation - +0.5-1mg/day