Erythromycin is a macrolide antibiotic discovered in 1952 that inhibits bacterial protein synthesis and growth. It is produced through fermentation of Streptomyces bacteria and extracted for use as an alternative to penicillin in individuals with penicillin allergies. Erythromycin contains a macrocyclic lactone ring with sugars attached and has bacteriostatic or bactericidal effects depending on concentration. It is commonly used to treat respiratory, genital, and eye infections caused by bacteria and chlamydia when penicillin cannot be used.

1. Erythromycin
By: Aachal D. Jain
Roll No.: 07
Class: Msc –II
Paper: 3

2. INTRODUCTION
• Antibiotics are a type of antimicrobial drug used in
the treatment and prevention of bacterial infections. They may
either kill or inhibit the growth of bacteria.
• Discovered by : Alexander Fleming in 1928.
• Antibiotics can be bacteriostatic or bactericidal.
• The main classes of antibiotics:
• Aminoglycosides
• Cephalosporins
• Fluoroquinolones
• Macrolides
• Penicillins
• Tetracyclines

3. • Erythromycin-like antibiotics are also known as
macrolides.
• Macrolides belong to the polyketide class of natural
products.
• Macrolide antibiotics are are hydrophobic, basic
compound.
• Macrolide antibiotics slow the growth of, or sometimes
kill sensitive bacteria by reducing the production of
important proteins needed by the bacteria to survive.
• The commonly used macrolides are:
• Erythromycin
• Clarithromycin
• Roxithromycin
• Azithromycin

4. ERYTHROMYCIN
General Characteristics
• Erythromycin is a macrolide antibiotic that has an
antimicrobial spectrum similar to or slightly wider
than that of penicillin.
• Erythromycin was discovered in 1952 by McGuire
and coworkers from a strain of Streptomyces
erythreus.
• It is often used for people who have allergy to
penicillin.
• It is poorly soluble in water.
• Bactericidal, particularly at higher concentrations.
• Trade name is E-mycin or Erythrocin

5. GENERAL STRUCTURE
Erythromycin contains three characteristics parts in the molecule:
1. A highly substituted macrocyclic lactone: aglycone.
• It is a macrocyclic compound containing 14-membered lactone
ring with 10 asymmetric centers
2. A ketone group.
3. An amino desoxysugar: glycon, and in some of the macrolides,
a neutral desoxysugar which are glycosisically attached to the
aglycone ring.
• The two sugars are namely: L-Cladinose and D-Desoamine.
• Its chemical formula is C37H67N1O13.

7. MECHANISM OF ACTION
• Erythromycin displays a bacteriocidal activity
particularly at higher concentrations.
• It prevents the growth of bacteria by inhibiting their
protein synthesis.
• Erythromycin binds to the 23s rRNA molecule in the
50S ribosomal subunit.
• Binding site near the peptidyltransferase center.
• This binding blocks thee exit of the growing peptide
thus inhibiting the translocation of the peptides.
• Peptide chain elongation is also prevented.

9. BIOSYNTHESIS OF
ERYTHROMYCIN

10. INDUSTRIAL PRODUCTION
• Erythromycin is produced from Streptomyces
and Micromonospora.
• Erythroymycin is produced mainly by
submerged fermentation.
• During fermentation, different types of
erythromycin are produced like erythromycin
A, B, C, and D.
• The steps for erythromycin production are as
follows:

11. 1. Inoculum Development:
– Inoculum is prepared from suspension of at least 108
cells/ml.
– Sporulation of S.erythraeus is done on tryptone agar slant.
– Cells are harvested from agar plates and suspension is
taken in sterile water and stored at 4oC.
2. Medium:
• Sucrose– 5%
• Corn steep liquor – 0.5%
• Soyabean oil meal – 1.5%
• Yeast – 1.0%
• NaCl – 0.5%
• CaCo3 precipitate – 0.3%
• pH – 7.0 -7.2

12. 3. Fermentation :
• Fermentation is carried out in stirred tank
fermenter.
• It should have proper aeration and agitation, pH,
temperature, viscosity and dissolved oxygen
concentration.
• Temp: Fermentation temperature is 33oC.
• Duration: The length of fermentation is 3-7 days.
• Production of Erythromycin production occurs
when froth reaches stationary phase.
• Addition of n-propanol as precursor increases
the production of erythromycin.

13. 4. Isolation:
• Mycelium is separated from the broth by filter
press, centrifugation or drum filtration.
• Acidic condition helps to separate mycelium the
broth.
• Acidic condition is maintained by addition of
Butyl acetate which favors the separation of the
mycelium. Also it dissolves the antibiotic.
• It is then washed with water.

14. 5. Extraction:
• It is extracted using methyl iso butyl ketone or
ethyl acetate.
• It is then transferred to acidic water.
• pH is adjusted with HCl, acetic acid and citric acid.
• Purification and concentration is carried out in ion
exchange resin amberlite 50.
• Elution is carried out by a mixture of organic
solvents and water at pH 3 to 8.
• Erythromycin is obtained as dihydrate salt.
• The dehydrate crystals of erythromycin are filtered
and dried on vaccum tray dryer.

15. CLINICAL USES
• Drug of choice in corynebacterial infections:
diphtheria, corynebacterial sepsis, erythrasma.
• In respiratory, neonatal, ocular, or genital
chlamydial infections.
• Treatment of community-acquired pneumonia.
• Penicillin substitute in penicillin allergic
individuals.
• Prophylaxis against endocarditis during dental
procedures in individuals with valvular heart
disease.

16. Thank You