Partial Characterization of Bacteriocin Producced by Native Isolates Of Enteroccocus and Pediococcus Species

Akshatha, A. (2008) Partial Characterization of Bacteriocin Producced by Native Isolates Of Enteroccocus and Pediococcus Species. [Student Project Report]

PDF Pr-419.pdf Restricted to Repository staff only Download (1MB)

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:	73 5. SUMMARY AND CONCLUSION LAB are widely used as a starter culture in food fermentation. The production of fermented foods is based on the use of starter cultures, for instance LAB that initiate rapid acidification of the raw material. Recently, new starter cultures of lactic acid bacteria with an industrially important functionality are being developed. They can contribute to the microbial safety or offer one or more organoleptic, technological, nutritional, or health advantages. Examples are LAB that produce antimicrobial substances, sugar polymers, sweeteners, aromatic compounds, vitamins, or useful enzymes, or that have probiotic properties. In this study bacteriocin producing LAB was identified as Enterococcus faceum and Pediococcus pentosaceus by microbial, biochemical methods, immunity protein production from naturally fermented Idli batter and from fish intestine respectively. Initial characterization was based on their anti-listerial activity, the native isolates showed antagonistic activity against several Listeria, Pediococcus and other species Based on the Scanning electron microscopic (SEM) observation cultures E1, ΔE1, S6(b) and S5 showed cocci morphology with smooth texture. Characterization of these cultures revealed that they can grow at high NaCl concentration (9.6%) and even survival at high temperature (700C). Cultures E1, ΔE1, S6(b) and S5 showed no hydrolysis of starch and gelatin confirming their ability of not producing amylase and gelatinase. Mutant characterization also confirmed that it belongs to Enterococcus species and it has lost its capacity of producing antimicrobial compounds. Bacteriocin characterization revealed that it did not lose its activity even when subjecting it to high temperature of 121°C. Antimicrobial activity against certain proteolytic enzymes also confirmed that this antimicrobial compound is proteinaceous. Molecular characterization of Bacteriocin by Tricine SDS PAGE confirmed the molecular weight of the protein to be <5kDa and they belong to Class II of lower molecular weight bacteriocin and are heat stable bacteriocin. The genus Enterococcus comprises of different species. There is a considerable phenotypic diversity between these species. Modern genotypic identification methods like 16S rRNA targeted gene probes are able to differentiate these species. For the most important species in the gastro- intestinal tract or in food or feed, like E. faecium reliable phenotypic identification systems (e.g. growth temperatures, fermentation pattern, selective media) are applicable, too. Ecologically, enterococci are typical lactic acid bacteria and are part of the autochthonous gut flora of man and production animals. Consequently they are also part of the microflora of fermented food like that of idli batter. They are applied as starter or protection cultures including probiotics in food and feed. Safety aspects should include careful examination of the antibiotic resistance gene.
Uncontrolled Keywords:	Bacteriocin Antimicrobial activity Lactic acid Bacteria native isolates Entercococcus faceum Pediococcus pentosaceus
Subjects:	500 Natural Sciences and Mathematics > 07 Life Sciences > 04 Microbiology
Divisions:	Food Microbiology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	03 Nov 2008 11:35
Last Modified:	28 Dec 2011 10:06
URI:	http://ir.cftri.res.in/id/eprint/8802

Actions (login required)

View Item