The cow dung samples were collected from the village of Burdwan
district, West Bengal, India, in plastic bags by sterilized
spatula and stored in an ice box for approximately 12 h. It was brought to the laboratory for isolation of cellulolytic bacteria.
One gram of cow dung sample was suspended with 100 ml of
distilled water and was homogenized by constant shaking using
an orbital shaker for 2 h at 180 rpm. Serial dilutions from 106
to 107 were prepared using sterilized distilled water. An aliquot
of 100 lL of each dilution was spread plated onto Omeliansky’s
agar medium (Omeliansky, 1902) [g/L (W/V), (NH4)2SO4 1;
K2HPO4 1; MgSO4.7H2O 0.5; NaCl traces; carboxymethyl
cellulose (CMC) 1%,pH7] and incubated at 37 C. Morphologically
dissimilar and discrete colonies were picked from different
dilution plates and streaked on separate Omeliansky’s agar
medium and incubated at 37 C for 96 h. The replica plates were
also prepared separately for staining. Cellulase producing bacteria
were screened by congo red staining (Teather and Wood,
1982) and C1 strain was selected as potent cellulolytic bacteria
(colony showing largest zone of decolorization).