penicillin production microbiology

1. MICROBIOLOGY APPLIED
ASSIGNMENT
PRODUCTION OF
PENICILLIN

2. INTRODUCTION:
Penicillin is an antibiotic producedby
Penicilliumnotatumand P.chrysogenum.
Penicillin is an bactericidal
It inhibits the synthesis of cell wall of the
bacteria
It has no effect on gram negative bacilli
Penicillin has been isolated is various closely
related forms called F,G,K,X,O and V
The mould from which fleming isolated
penicillin was later identified as Penicilliumnotatum
A variety of moulds belonging to otherspecies
and genera were later found to yield greater amounts of
the antibiotic and a series of closely related penicillins
PRODUCTION:
Penicillin was producedby a surface culture
method early in world war ІІ.Sub merged culture
methods were introduced by 1943 and are now almost
exclusively employed.

3. Penicillin production needs strict asceptic
conditions. Contaminationby other microorganisms
reduce the yield of penicillin This is caused by the
widespread occurenceof penicillinaseproducing
bacteria which inactive the antibiotic
Secondary,penicillin productionalso needs
tremendousamount of air.In all methods,deeptanks
with a capacity of several thousand ballonsare filled
with a culturemedium
The medium consists of corn-steep
liquor,lactose,glucose,nutrientsalts,phenyl,aceticacid or
a derivative and calcium
Carbonateas buffer,the medium is inoculated
with a suspension of conidia of
Penicilliumchrysogenum.The medium is constantly
aerated and agetated,and the mould grows throughout as
pellets
After about seven days growth is complete,the
pH rises to 8.0 or above, and penicillin production
ceases
METHODS:
Removal of mycelium
Countercurrent solvent extraction
Treatment of crude extract

4. PHASE І PHASE ІІ PHASE ІІІ
Mycelium Rapid growth
high N
content
Slow growth
N content
lower
Decrease in
dry weight
and N content
rise
pH sharp rise plateau (or)
slight fall
used more
rapidly
-
Lactose Used slowly More rapidly exhausted
Lactic acid Exhausted
rapidly
_ _
Ammonia Released into
medium
Utilized Released into
medium
Non-
ammonia N
Used
excessively
Concentration
stable
Increased
Concentration
Nitrate Used slowly Used slowly Used slowly
When the fermentation is complete,themasses of mould
growth are separated from the culturemedium by
centrifugation and filteration.

5. The complex process of extracting the penicillin from
the clear fluid then begins.The method involves various
extractions with organic solvents and recrystallization
Penicillin is assayed to determine its potency
before being bottledand sold
The potencyof a batch of pencillin is determined
by a biologic assay in which the unknown is compared
with a standard preparationof crystalline sodium
penicillin.G
Cylinder-platemethod is used to determine the potency
of penicillin
The test consist of adding nutrient agar,previously
inoculatedwith a specified strain of staphylococcus
steel cylinder open at both the ends are placed on the
agar
This cylinders are filled with suitable dilution of the
working standardsof penicillin and the unknown
sample
It is incubated at 37⁰C for 16-18 hours.
It diameters of the zones of inhibition of the bacterial
growth are measured

6. The antibiotic activity of the unknown sample is
determined by comparing its zones of inhibition with
those of the standard penicillin
REFERENCES:
1.Microbiology:General and applied
Professor A.Mani
2.General microbiology:Dr.C.B.Powar
(volume ІІ)