Rifamycin is a new group of antibiotics obtained from Nocardia mediterranea, Sterptomyces sp, and Micromonospora locustis. It contains five active substances including Rifamycin B, which is the most active and spontaneously transforms into more active forms. Rifamycin SV shows good activity against gram-positive bacteria infections. Nocardia mediterranea is maintained through lyophilization or frozen mycelium storage. Optimal fermentation occurs at 28C using 5% inoculum over 300 hours with oxygen levels between 0.8-1.5 l/min. Purification involves filtration, acidification, extraction and crystallization.

1. Rifamycin

2.  It is a new group of antibiotics obtained from
 Nocardia mediterranea
 Sterptomyces sp
 Micromonospora locustis.
Substances of Rifamycin:
 The isolated product has five active substances.
 Rifamycin A,B,C,D and E.

3.  Rifamycin B is the most active of all . It is
spontaneously transforms to more active
products like rifamycin O,S and SV. These are
microbiologically active.
 In vivo Rifamycin SV shows good activity ,
tolerability and solubility properties and it
treats infection from gram positive bacteria

4.  Stock Cultures of Nocardia mediterranea is
maintained insealed ampoules in lyophilized
state.
 Frozen vegetative mycelium of selected high
producing colonies in small vials at a low
temperature are highly stale over a long
period of storage.

5.  Vegetative Medium includes:
 Peanut meal (25g/l)
 Soyabean Meal (10g/l)
 Ammonium sulphate (10g/l)
 Propylene Glycol (5g/l)
 Glucose (110g/l)
 Fish Meal (20-40g/l)

6.  Best yield can be obtained when 5% inoculum
of a preculture grown for 24 hours is used in
aerated fermenters at 28 C
 It give a yeild of 6-7 g/l
 During fermentation N.mediterranea has high
oxygen requirements in a definite period of
growth production cycle.
 An air flow ranging from 0.8-1.5 l/min is
essential.

7.  It is carried out in conventional bioreactors
of 20-100 m3 volume.
 It is equiped with turbine , stirrers , baffles ,
air ring spargers and heating-cooling systems,
 In a fermenter. Consumption of glucose ,
growth of mycelium and production of
antibiotic occur at the same time.
 At initial stages of growth , consumption of
glucose and nitrogen is slow , however , it
becomes very fast when mycelial growth
starts.

8.  The demand of oxygen is also very high at
this stage .
 Metabolic activity of mycelium changes the
initial pH 6.2-6.4 to 6.6-6.7 , later it
decreases to 5.5-5.7 .pH again rises slowly
until the end of fermentation and optimal pH
6.2-6.4
 The fermentation lasts for 300 hrs

9.  Purification of Broth after harvest is done at
pH 7.5-8.0.
 The filterate is acidified (pH 2.0)
 Extraction of the product is carried with
choloform , Re-extraction from chloroform is
done in phosphate buffer of pH 8 followed by
acidification of the aqueous solution and
extraction with ethyl acetate from which it
crystallizes