Characterization of Exopolysaccharide Produced by Streptococcus thermophilus CC30.

ABSTRACT: An exopolysaccharide (EPS) producing strain CC30 was isolated from raw milk and identified as Streptococcus thermophilus with morphological and 16S sequencing analysis. The strain was shown to produce 1.95?g/L of EPS when grown in skim milk lactose medium at 30°C by increasing the viscosity of the medium. The EPS was isolated and purified, and it was shown to consist of glucose and galactose in 1?:?1 ratio, with molecular weights ranging from 58 to 180?kDa. FTIR spectroscopy indicated the EPS to have amide, hydroxyl, and carboxyl groups. Under Atomic Force Microscopy, EPS showed spike-like lumps of EPS. Scanning Electron Microscopy (SEM) studies showed that it had irregular lumps with a coarse surface. The EPS displayed pseudoplastic nature. Thermogravimetric analysis (TGA) reported a degradation temperature of 110.84°C. The purified EPS exhibited reducing activity, hydrogen peroxide radical scavenging activity, and emulsification activity. The results of the present study indicated that EPS producing Streptococcus thermophilus could serve as a promising candidate for further exploitation in food industry.

SUBMITTER: Kanamarlapudi SLRK 

PROVIDER: S-EPMC5549498 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature