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Characterization Of Exopolysaccharide Produced By Leuconostoc Sp Cfr 2181 & Lactobacillus Sp Cfr 2182

Palanivel, G. (2006) Characterization Of Exopolysaccharide Produced By Leuconostoc Sp Cfr 2181 & Lactobacillus Sp Cfr 2182. [Student Project Report]

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Abstract

This Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page.

Item Type: Student Project Report
Additional Information: Microbial exopolysaccharides are biothickners that can be added to a wide variety of food products, which can serve as stabilizers, gelling agents, viscosifying agents. EPS are produced by several bacterial and yeast species which are having promising scope in food and allied Industries. EPS also provide a protective covering to the micro-organisms to overcome the adverse conditions of the environment. More recently polysaccharides are being exploited in the drug delivary and delayed drug released formulations. This study is focused on production and purification of EPS in large quantity and partial characterization of EPS. In the purification studies the EPS precipitated using alcohol was dialyzed and lyophilized. It appeared creamy whitish in colour indicating that the EPS is free from media components and low mol wt compounds. Since the media components contained less protein content and glucomannas, the dialysis process appear to be more simple and efficient in the getting of pure EPS. The main focus of the present study was partial characterization of the EPS produced by Leuconostoc sp CFR 2181 and Lactobacillus sp CFR 2182. The physical properties of the dialyzed EPS of Leuconostoc sp CFR 2181 showed solid thick mass in appearance, tasteless soluble in water and alkali with no gelling and film formation. The physical properties of Lactobacillus sp showed solid smooth pluffy appearance, tasteless, soluble in water and alkali with no film and gel formation. The proximate composition of EPS produced by Leuconostoc sp CFR 2181 showed total sugar 84%, reducing sugar 11.2%, protein 0.8%, uronic acid 0.63% with moisture content of 2% and the EPS of Lactobacillus sp CFR 2182 showed total sugar 74%, reducing sugar 10.6%, protein 0.7%, uronic acid 0.6% and moisture content of 2%. The enzymatic action of EPS produced by Leuconostoc sp showed the absence of α – (1→ 4) and presence of α – (1→ 6) linkage. But on the EPS of Lactobacillus sp showed the presence of α – (1→ 4) linkages in traces and α – (1→ 6) linkage. The Gel permeation chromatography of EPSs of both Leuconostoc sp CFR 2181 and Lactobacillus sp CFR 2182 showed 3 peaks each, indicated the heterogenecity of the EPS. The molecular weight of EPS fractions (H1 H2, H3) of Leuconostoc sp had 15,14,000, 4,77,000 10, 232 daltons, respectively and the molecular weight of EPS fractions (D1 D2, D3) of Lactobacillus sp showed 13,18,000 2,29,100 and 33,100 daltons respectively which indicates that EPS are of highly heterogeneous. The high performance liquid chromatography of native EPS and fraction EPS of both Leuconostoc sp CFR 2181 and Lactobacillus sp CFR 2182 showed different peaks indicating the heterogenecity of the EPS. The 13 C NMR studies of native EPS of both Leuconostoc sp CFR 2181 and Lactobacillus sp CFR 2182 revealed that chemical shift of EPS are quite similar to dextran but 1H NMR studies showed that chemical shift of protons of EPS are quite overlapping indicates the heterogenicity of the molecule.It is concluded that further studies on characterization of these two exopolysaccharides are required especially with regard to monomer composition, linkage pattern to check for the presence of β-linkage, branching pattern and elucidation of complete structure of each EPSs and its application to food dairy and other industries.
Uncontrolled Keywords: Exopolysaccharide Leuconostoc Lactobacillus microbial polymers
Subjects: 500 Natural Sciences and Mathematics > 04 Chemistry and Allied Sciences > 27 Polymer Chemistry
500 Natural Sciences and Mathematics > 07 Life Sciences > 04 Microbiology
500 Natural Sciences and Mathematics > 04 Chemistry and Allied Sciences > 28 Polysaccharide Chemistry
Divisions: Food Microbiology
Depositing User: Food Sci. & Technol. Information Services
Date Deposited: 22 Dec 2006
Last Modified: 28 Dec 2011 09:26
URI: http://ir.cftri.com/id/eprint/374

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