Steroids share a common cyclopentanoperhydrophenanthrene ring structure and include various hormones. They can be classified as sterols, bile acids, cardiac glycosides, or steroid hormones. Steroid hormones include glucocorticoids, mineralocorticoids, androgens, estrogens, and progestogens which help control various metabolic and developmental processes. Several identification tests can be used to identify specific steroids like cholesterol, bile acids, and cardiac glycosides based on color changes produced from reactions with different reagents.

1. STEROIDS

2. • steroids possess a common structure –
PERHYDROCYCLOPENTANOPHENANTHRENE
NUCLEUS (RPS)
• includes cholesterol, bile acids, androgens,
adrenocortical, adrenomedullary, estrogenic, and
progestational hormones

3. CLASSIFICATION

4. STEROL
• Sterol
• also known as steroid alcohols
• occur naturally in plants, animals, and fungi, with the most
familiar type of animal sterol being cholesterol
• TYPES:
• Phytosterols – plant sterol ( campesterol, sitosterol,
and stigmasterol)
• blocks cholesterol absorption sites in the human intestine, thus
helping to reduce cholesterol in humans
• Zoosterol – animal sterol (cholesterol)
• Ergosterol – sterol present in the cell membrane of fungi

5. BILE ACIDS
• Bile acids
• are steroid acids found predominantly in the bile of
mammals and other vertebrates
• are conjugated with taurine or glycine in the liver,
forming bile salts
• Primary bile acids are those synthesized by the liver
• Secondary bile acids result from bacterial actions in the colon
• 2 functions:
• to remove unwanted cholesterol from the body
• to aid in lipid digestion in the intestine

6. CARDIAC GLYCOSIDE
• Cardiac Glycosides
• are glycosides of mostly C23-steroidal compounds
• are called cardiac glycosides because they modify heart
action
• MEDICINAL IMPORTANCE:
• They are cardiotonics used to treat Congestive heart failure
(CHF)
• They increase force of contraction of cardiac muscles
without increase oxygen consumption
• Increase cardiac output
• The diastolic phase last longer so decrease heart rate
• Have diuretic effect due to increase amount of blood
passing through the kidney

7. STEROID HORMONES
• Steroid hormones
• a steroid that acts as a hormone
• can be grouped into five groups by the receptors to which
they bind: glucocorticoids, mineralocorticoids,
androgens, estrogens, and progestogens
• Steroid hormones help control:
• metabolism, inflammation, immune functions, salt and
water balance, development of sexual characteristics, and
the ability to withstand illness and injury

8. CLASSES of STEROID HORMONES
• Glucocorticoids
• Glucocorticoids originate in the adrenal cortex and affect mainly
metabolism in diverse ways; decrease inflammation and increase
resistance to stress.
• Cortisol: dominant glucocorticoid in humans, synthesized from
progesterone in the zona fasciculata of the adrenal cortex,
involved in stress adaptation, elevates blood pressure and
Na+ uptake, numerous effects on the immune system
• Mineralocorticoids
• Mineralocorticoids originate in adrenal cortex and maintain salt
and water balance.
• Aldosterone: the principal mineralocorticoid, produced from
progesterone in the zona glomerulosa of adrenal cortex, raises
blood pressure and fluid volume, increases Na+uptake

9. CLASSES of STEROID HORMONES
• Estrogens
• Estrogens originate in the adrenal cortex and gonads and primarily
affect maturation and function of secondary sex organs (female
sexual determination)
• The natural estrogenic hormones are estradiol, estrone, and estriol,
produced in the gonads, adrenals, and placenta
• Estradiol: an estrogen, principal female sex hormone, produced
in the ovary, responsible for secondary female sex characteristics
• Androgens
• Androgens originate in the adrenal cortex and gonads and
primarily affect maturation and function of secondary sex organs
(male sexual determination)
• Testosterone: an androgen, male sex hormone synthesized in the
testes, responsible for secondary male sex characteristics,
produced from progesterone; most potent androgen in blood

10. CLASSES of STEROID HORMONES
• Progestins
• Progestins originate from both ovaries and placenta, and
mediate menstrual cycle and maintain pregnancy
• Progesterone: a progestagen, produced directly from
pregnenolone and secreted from the corpus luteum,
responsible for changes associated with luteal phase of the
menstrual cycle, differentiation factor for mammary glands

11. IDENTITY TESTS for
STEROLS
IDENTIFICATI
ON TEST
REAGENTS
USED
POSITIVE
RESULT
COMPOUNDS
POSITIVE FOR
THE TEST
Rosenheim
Reaction
CHCl3 + aq.
Trichloroacetic
acid sol’n
 RED color 
BLUE color
sterol
Tortelli-Jaffe
Reaction
Glacial Hac +
sol’n of Br2 in
CHCl3
 GREEN color
at the interface
sterol

12. IDENTITY TESTS for
CHOLESTEROL
IDENTIFICATI
ON TEST
REAGENTS
USED
POSITIVE
RESULT
COMPOUNDS
POSITIVE
FOR THE
TEST
Liebermann-
Burchard’s test
Acetic anhydride
+ H2SO4
 GREEN color Cholesterol
Salkowski
reaction
+ CHCl3 soln
+ H2SO4
 RED color
 GREEN
FLUORESCENCE
Cholesterol

13. IDENTITY TESTS for
CHOLESTEROL
IDENTIFICATI
ON TEST
REAGENTS
USED
POSITIVE
RESULT
COMPOUNDS
POSITIVE FOR
THE TEST
Tschugaeff
Method
Cholesterol in
CHCl3 in glacial
Hac + ZnCl2 and
acetyl chloride +
heat
 RED color cholesterol

14. IDENTITY TEST for BILE ACIDS
IDENTIFICATI
ON TEST
REAGENTS
USED
POSITIVE
RESULT
COMPOUNDS
POSITIVE FOR
THE TEST
Mylius Reaction  BLUE color in
transmitted light
and needles,
which appear
YELLOW in
reflected light
Cholic acid
Hammarsten Test HCl + alcohol
+ heat
 VIOLET color
 YELLOW
color
Cholic acid
Pettenkofer
Reaction
+ heat  RED color
 BLUISH RED
in several days
Cholic acid

15. IDENTITY TESTS for CARDIAC GLYCOSIDES
IDENTIFICATI
ON TEST
REAGENTS
USED
POSITIVE
RESULT
COMPOUNDS
POSITIVE FOR
THE TEST
Keller-Kiliani’s
Test
FeCl3 + conc.
H2SO4
 REDDISH
BROWN color 
BLUE/PURPLE
Deoxysugars
Libermann-
Burchard Test
Residue in CHCl3
+ acetic anhydride
+ conc H2SO4
 IMMEDIATE
COLOR
CHANGE 
BLUE – GREEN,
RED, PINK,
PURPLE/VIOLE
T
Aglycone
steroidal group

16. IDENTITY TESTS for
CARDIAC GLYCOSIDES
IDENTIFICATI
ON TEST
REAGENTS
USED
POSITIVE
RESULT
COMPOUNDS
POSITIVE FOR
THE TEST
Kedde’s Test CHCl3 soln of
residue +Kedde’s
reagent A (3,5
dinitrobenzoic
acid) + Kedde’s
reagent B (NaOH)
 VIOLET color Unsaturated
lactones