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Chapter
4
Vitamins
目录
James Lind
目录
Christian Eijkman (Ducth) found
Vit.B1 ( Nobel Prize for Medicine
and Physiology ,1929)
Albert Szent-Gyorgyi (Hungarian)
found Vit.C ( Nobel Prize for
Medicine and Physiology ,1937)
Dam (Dane) found Vit.K ( Nobel Prize for
Medicine and Physiology ,1943)
目录


Vitamin
Concept：
vitamins
organic
are
chemically
compounds
that
unrelated
cannot
be
synthesized in adequate quantities by
humans and, therefore, must be supplied
by the diet.
目录
Characteristics：
1. neither the component of the organization
nor the energy material ；
2. the requirement is limited.
3. It can not be synthesized by humans (or a
little), and must be supplied by diet 。
目录
Classification:
Fat-soluble Vitamin ：
Vitamin A、D、E、K
Water-soluble Vitamin ：
B-Complex vitamin,
Vitamin C
B-Complex vitamin：Bl, B2, PP, B6, pantothenic
acid , biotin, Folic acid, B12 , etc.
目录
Section 1
Fat-soluble Vitamin
目录
•
Common characteristics：
（1）Lipid soluble ；
（2）They are released, absorbed and
transported with the fat of diet
（3）They are transported with lipoproteins
or some special binding proteins in blood；
（4）They are stored in the liver and
adipose tissue.
• Types： Vit A, Vit D, Vit E, Vit K
目录
Ⅰ. Vitamin A
1. The chemical natures and properties
(1) Natural forms
A1——Retinol，mainly exists in livers of mammals
and seawater fish;
A2——3-dehydrogenation retinol，mainly exists in
livers of freshwater fish.
(2) Active forms：
Retinol, retinal, retinoic acid
目录
(3) Sources：
animal giblets,
plants——Vitamin A former（e.g. β- Carotene）
15／
15／
β- Carotene
（VitA原）
CH2 HO
2×
VitA
目录
2. Function and deficiency diseases
(1) It is a component of the visual pigments of
rod and cone cells
Rod cells： Rhodopsin ＝ opsin ＋ 11-cis retinal
Deficiency diseases: Night blindness
目录
(2) It is essential for normal differentiation of
epithelial tissues and mucus secretion.
Deficiency diseases:
Xerophthalmia
Darier disease
Xerosis cutis
目录
(3) It influences the cell differentiation
(4) It is an efficient antioxidant
目录
Ⅱ.
Vitamin D
1. The chemical natures and properties
(1) Types：VitD2 ：in plants
VitD3 ：in animal tissue
7-Dehydrocholesterol
Ergosterol
UV
UV
VitD3
VitD2
目录
(2) Active form of VitD3：1, 25- (OH)2-VitD3
Vit D3
Liver
Kidney
25-OH-VitD3
1, 25-（OH）2-VitD3
目录
(3) Sources ：
cod liver oil, animal liver, eggs…
目录
2.
Function and deficiency diseases
(1) Maintain adequate plasma levels of calcium
(2) It influences the cell differentiation
目录
(3) Deficiency diseases ：
children——rickets
adults——osteomalacia
目录
(4)
Toxicity of vitamin D
High doses can cause loss of
appetite ，nausea , hypercalcemia , etc.
目录
Ⅲ.
Vitamin E
1. The chemical natures and properties
(1) Types：tocopherol ，
（、、 and ）
tocotrienols
(2) Sources：
Vegetable oils are rich sources of
vitamin E.
目录
2.
Function and deficiency diseases
(1) Antioxidation
deficiency diseases: hemolytic anemia
目录
Clinical practice
(2) Prevent and cure the threatened abortion
and habitual abortion
deficiency diseases: sterility
(3) Promote the metabolism of protoheme
deficiency diseases: Neonatal anemia
目录
Ⅳ. Vitamin K
1. The chemical natures and properties
(1) Natural forms：K1---- phylloquinone
（in plants）
K2----menaquinone
（in intestinal bacterial）
(2) Synthetic： K3、K4
目录
(3) Sources：
Plants；intestinal bacterial
2.
Function and deficiency diseases
It is required in the synthesis of prothrombin
and blood clotting factors.
目录
deficiency diseases: bleeding easily
目录
Section 2
Water-soluble Vitamin
目录

Common characteristics
• Water-soluble and readily excreted in the urine.
• They must be absorbed from the food frequently
and can not be stored.
• They are precursors of coenzymes for the
enzymes.

Types：B-Complex vitamin, Vitamin C
目录
Ⅰ. Vitamin B1
1. The chemical natures and properties
(1)
Vit. B1------- thiamine
(2) Active form: thiamine pyrophosphate
( TPP)
N
CH2
H3C
+
N
NH2 HC
N
CH3
S
CH2
O
O
CH2
O
P
OH
O
P
OH
OH
硫胺素(thiamine)
TPP
目录
(3) Sources：
In many foods.
目录
2.
Function and deficiency
diseases
(1) TPP is the coenzyme for the
pyruvate dehydrogenase.
deficiency diseases: beriberi
目录
(2) TPP is the coenzyme for transketolase in
pentose phosphate pathway.
(3) Inhibit the activity of cholinesterase.
deficiency diseases: indigestion
目录
Ⅱ. Vitamin B2
1. The chemical natures and properties
（1）Vit. B2 ------ riboflavin
（2）Active forms:
Flavin mononucleotide (FMN）
Flavin adenine dinucleotide (FAD）
目录
NH2
N
N
O
O
H2C
O
HCOH
O
P
OH
P
N
O
CH 3
N
O
OH
HCOH
HCOH
OH
CH 3
N
H3C
Ⅲ
H3C
Ⅱ
N
N
O
C
Ⅰ
C
OH
NH
O
Vit B2
FMN
AMP
FAD
目录
(3) Sources:
Milk and milk products, liver, eggs,
meat, etc
2.
Function and deficiency diseases
FMN and FAD are the prosthetic group
for oxidation-reduction enzyme, which can
reversibly accept two hydrogen atoms.
目录
deficiency diseases:
Cheilitis
angular stomatitis
目录
Ⅲ. Vitamin PP
1. The chemical natures and properties
(1) Vit. PP including：niacin
nicotinamide
(2) Active forms:
nicotinamide adenine dinucleotide
(NAD+)
nicotinamide adenine dinucleotide phosphate
(NADP+)
目录
Nicotinamide
NH2
CONH2
N
N
N+
N
N
OH
HO
OH
OH
OH
O
H2C
O
P
O
O
NAD+：R为
H
NADP+：R为
P
O
O P
O
CH2
O
O
OH
OR
OH
P
OH
O
AM
P
目录
(3) Sources：
In many foods.
2.
Function and deficiency diseases
 They are the coenzymes for anaerobic
dehydrogenase
目录
deficiency diseases: pellagra
3D：dermatitis、diarrhea、dementia。
目录
Ⅳ. Pantothenic acid
1. The chemical natures and properties
(1) pantothenic acid
(2) Active forms: coenzyme (CoA)
acyl carrier protein
(ACP)
(3) Sources：
Widely distributed
(plants, animals, intestinal bacterial…)
目录
H2N
N
O
N
N
HO
P
O
AMP
N
CH2
CoA的结构式
O
O
HO
OPO 3H2 OH
CH2
P
O
O
H3C
HO
C
CH3
泛酸
C H
4-磷酸泛酰
巯基乙胺
CO
NH
H2C
O
CH2
C
NHCH2CH2
SH
目录
2.
Function and deficiency diseases
They are the coenzymes for acyltransferase.
目录
Ⅴ. Biotin
1. The chemical natures and properties
(1) Types：
α-biotin——in yolk
β-biotin——in liver
(2) Sources ：
Biotin deficiency does not occur
naturally because it is widely distributed in food. It also
can supplied by intestinal bacteria in humans.
目录
2.
Function and deficiency
diseases
(1) It is a prosthetic group for carboxylase.
(2) It takes part in signal transduction and
gene expression
目录
Ⅵ. Vitamin B6
1. The chemical natures and properties
(1) Types：
pyridoxine, pyridoxal, pyridoxamine
(2) Active forms:
pyridoxal phosphate
pyridoxamine phosphate
目录
2.
Function and deficiency
diseases
(1) Pyridoxal phosphate is the coenzyme for
aminopherase and decarboxylase.
(2) Pyridoxal phosphate is the coenzyme for ALA
synthase.
目录
(3) Pyridoxal phosphate is the coenzyme for
enzyme of hyperhomocysteinemia catabolism.
deficiency diseases:
no deficiency in general.
目录
Ⅶ. Folic acid
1. The chemical natures and properties
F
Dihydrofolate
reductase
NADPH+H+
Dihydrofolate
(FH2)
NADP+
Dihydrofolate
reductase
NADPH+H+
FH4
NADP+
(1) Active form: Tetrahydrofolate (FH4)
(2) Sources ：
It is widely distributed in green plants
In liver
目录
2.
Function and deficiency
diseases
FH4 plays a key role in one-carbon metabolism,
is essential for the biosynthesis of nucleic acid.
deficiency diseases: megaloblastic anemia
Normal marrow
Megaloblastic marrow
目录
Ⅷ. Vitamin B12
1. The chemical natures and properties
(1) Vit. B12------- cobalamine
(2) Active forms:
Methylcobalamin
5
(3) Sources ：
- deoxyadenosylcobalamin
Liver, kidney, lean meat, fish, eggs, etc.
目录
CH2OH
O H
HH
H
O
O
P
O
CH3
O
CH
R：-CH3
OH N
CH3
N
CH3
R：5`-脱氧腺苷
CH2
CONH2
NH
CH2
CO
H
CH3
CH2
CH3
H
N
Co+
D
CH3 N
CH3
CH3
H C
C
CH2
H
CH2
CH2
CH3
CH2
N
A
R
CH2
CH2
CONH2
N
CONH2
CH2
CH
CH2
B CH3
C
H
CH3
CH2
CONH2
目录
2.
Function and deficiency
diseases
It plays key roles in methyl transfer and onecarbon metabolism.

deficiency diseases:
hyperhomocysteinemia
megaloblastic anemia
目录
Ⅸ. Vitamin C
1. The chemical natures and properties
(1) Vit. C------ ascorbic acid
(2) Strong reducing ability, unstable.
(3) Sources ：
It is widely distributed in fresh vegetables
and fruits.
目录
2.
Function and deficiency
diseases
(1) Participate in REDOX reaction;
(2) Participate in the transformation of cholesterol;
(3) Protect sulphur enzyme can not be oxidated;
(4) Combined with the heavy metal ions and ruled
out of the body.

deficiency diseases: Scurvey
目录