Original Articles: 2013 Vol: 5 Issue: 12
Screening of carbon sources/prebiotics and amino acids in the medium for Streptococcus thermophilus using PlackettÃ?¢Ã?â?¬Ã?â??Burman design
Abstract
Previous studies have shown that the carbon sources/prebiotics and amino acids have an important influence on the growth of Streptococcus thermophilus. Out of consideration of the optimal substances for growth of Streptococcus thermophilus, viable counts was studied in the medium containing various carbon sources/prebiotics (glucose, sucrose, lactose, fructose, maltose, xylooligosaccharides, fructooligosaccharides, galactooligosaccharides, isomaltooligosaccharide, stachyose, inulin) and amino acids (glutamate, glycine, serine, leucine, valine, lysine, threonine, phenylalanine, arginine, aspartic and Vc). The results indicated that xylooligosaccharides, lactose and isomaltooligosaccharide out of selected carbon sources/prebiotics affect the growth of Streptococcus thermophilus markedly. In addition, these three variables showed all positive effect. Glutamate, lysine and valine in the investigated amino acids showed a significant effect on the growth of Streptococcus thermophilus; moreover, glutamate and lysine had a positive effect on it, but valine negative. Overall, isomaltooligosaccharide and glutamate were the most efficient selected prebiotics and amino acids with positive impact on the growth of Streptococcus thermophilus, respectively.