|
Untitled 1
|
 |
ANNUAL CONFERENCE :: Abstract Library
Abstract Library
2003 Conference Abstract
| Type of Submission |
 |
Submission Type: |
Poster Presentation |
|
Subject Category: |
Microbial Physiology |
|
| Session Information |
|
Presentation Date: |
May 27, 2003 |
|
Abstract ID: |
E9 |
|
Session: |
Poster 2 |
|
Time: |
15:00 |
|
| Presenting Author |
|
| Other Authors |
|
Z. FALLAHI, Azzahra University
A. ABDI-ALI, Azzahra University
F. JALILVAND, Azzahra University
S. SEPEHR, Azzahra University
|
|
| Title |
|
Growth Conditions Effect on Alginate Production from Pseudomonas aeruginosa |
|
| Abstract Text |
|
ALginate from Pseudomonas aeruginosa is composed of a linear copolymer of 1,4-b-linked D-mannuronic acid and its C-5 epimer, L-guluronic acid, in which the mannuronic acid residues are variably modified with O-acetyl groups. Due to the fact that mucoidy form is unstable and special growth conditions are effective on stabilizing mucoidal form and increasing alginate production, we investigated the effect of osmotic pressure in alginate production as one of the environmental growth conditions and studied the methods for isolating and measuring the quantity of alginate produced by mucoid strains of P.aeruginosa. A collection of 137 wild type P.aeruginosa obtained from different clinical sources (such as sputum, stool, urine and burns), from several hospital in Iran. Identification of mucoid and non-mucoid strains were done based on macroscopic characteristics, production of uronic acid and coagulation during ethanol addition. Assay for alginate was perfomed by carbazole method with borate. Several culture media used to increase the osmotic pressure, are as follows: MacConkey agar containing 0.25 M and 0.5 M NaC1, MacConkey agar containing glycerol (1-3% , 5% and 10%) and nutrient agar containing 1% glucose. Specimens were incubated in 10 tubes containing 10 ml of the above media at 25 C for 7 days. Alginate was extracted after centrifugation, precipitation with ethanol and dealcoholization and then dried in vaccum drier. MacConkey agar containing 2% glycerol was the best media for alginate production.The highest amount of alginate was isolated from sputum of a chronic bronchitis patient.This strain (strain 7101) produced 5212 mg/lit alginate on MacConkey agar containing 2% glycerol and 607 mg/lit on non glycerol medium. The lowset amount of alginate on glycerol medium related to a burn's specimen with 140mg /lit. Among strains of mucoid P.aeruginosa, only two strains, i.e. strain 7101 from sputum and strain 9557 from urine produced alginate on both of MacConkey agar with and without glycerol. Alginate is used for a variety of industrial purposes, e.g. as a stabilizing, thickening and gelling agent in food production, or to immobilize cells in pharmaceutical and biotechnology industries.Due to the importance of alginate, its production is valuable. In this reserch, strain 7101 produced the highest amount of alginate on MacConkey agar containing 2% glycerol. These results indicate the role of glycerol in increasing of osmolarity and algintae production.Thus, alginate production relates to the kind of strain and clinical sources (eg, lungs), as well growth conditions.Key Word: Pseudomonas aeruginosa – alginate – production – growth conditions 1-Department of Biology, Faculty of Science, Azzahra University,Tehran,Iran 2-Institute of Biophysics and Biochemistry (I. B. B), Tehran University,Tehran,Iran abdialya@azzahra.ac.ir
|
|
|
|
|
