Monday, November 9, 2009
P43

Laboratory analysis of Exopolysaccharide production by Alcaligenes CMG634

Nazia Jamil, Microbiology & Molecular Genetics, University of the Punjab, New campus, Punjab University, Lahore, 54590, Pakistan and Nuzhat Ahmed, Centre for Molecular Genetics, University of Karachi, Karachi-75270, Karachi, 75270, Pakistan.

The strain CMG634 was attached bacteria and isolated from green seaweed. It produced viscous broth when supplemented with nutrient broth with 3%NaCl while in minimal media (ASW with glucose) it also produced viscous and yellowish broths. It produced translucent and gelatinous colonies on agar plates. Strain CMG634 (AY596795) was identified as Alcaligenes sp. IS-18, 16S ribosomal RNA gene sequence showed 87% homology to AY346137. Exopolysaccharide was analyzed by extracting the samples of broth at different intervals. When the isolated bacterium was grown at 30oC for a few days (1-5) on 3%NaCl nutrient broth. To study the nature of the exopolysaccharide production, partial purification of the extracted polysaccharide was done by dissolving and redissolving of the precipitates in water and extracted by ethanol. The partially purified polysaccharide was subjected to acid hydrolysis and neutral fractions were analyzed by thin layer chromatography. Extracted polymer was found to be Glycoprotein in nature. Hygroscopic analysis of extracted EPS showed that maximum water was absorbed by EPS of 5th day. Scanning and transmission electron micrographs showed both capsular and slime in form of micro fibril.