A Rapid and Easy Method for the Detection of Microbial Cellulases on Agar Plates Using Gram’s Iodine
IR@IHBT: CSIR-Institute of Himalayan Bioresource Technology, PalampurView Archive Info
A Rapid and Easy Method for the Detection of Microbial
Cellulases on Agar Plates Using Gram’s Iodine
Kasana , Ramesh C
Abstract Screening for cellulase-producing microorganisms
is routinely done on carboxymethylcellulose (CMC)
plates. The culture plates are flooded either with 1% hexadecyltrimethyl
ammonium bromide or with 0.1% Congo
red followed by 1 M NaCl. In both cases, it takes a minimum
of 30 to 40 minutes to obtain the zone of hydrolysis
after flooding, and the hydrolyzed area is not sharply discernible.
An improved method is reported herein for the
detection of extracellular cellulase production by microorganisms
by way of plate assay. In this method, CMC
plates were flooded with Gram’s iodine instead of the
reagents just mentioned. Gram’s iodine formed a bluishblack
complex with cellulose but not with hydrolyzed
cellulose, giving a sharp and distinct zone around the cellulase-
producing microbial colonies within 3 to 5 minutes.
The new method is rapid and efficient; therefore, it can be
easily performed for screening large numbers of microbial
cultures of both bacteria and fungi. This is the first report
on the use of Gram’s iodine for the detection of cellulase
production by microorganisms using plate assay.
Kasana , Ramesh C and Salwan, R and Dhar, H and Dutt, Som and Gulati, Arvind (2008) A Rapid and Easy Method for the Detection of Microbial Cellulases on Agar Plates Using Gram’s Iodine. Current Microbiology, 57 (5). pp. 503-507.