Production of D-tagatose, a low caloric sweetener during milk fermentation using L-arabinose isomerase |
| |
Authors: | Rhimi Moez Chouayekh Hichem Gouillouard Isabelle Maguin Emmanuelle Bejar Samir |
| |
Institution: | Laboratoire d'Enzymes et de Métabolites des Procaryotes, Centre de Biotechnologie de Sfax, Sfax, Tunisia. |
| |
Abstract: | Lactobacillusdelbrueckii subsp. bulgaricus and Streptococcus thermophilus are used for the biotransformation of milk in yoghurt. During milk fermentation, these lactic acid bacteria (LAB) hydrolyze lactose producing a glucose moiety that is further metabolized and a galactose moiety that they are enable to metabolize. We investigated the ability of L. bulgaricus and S. thermophilus strains expressing a heterologous L-arabinose isomerase to convert residual D-galactose to D-tagatose. The Bacillus stearothermophilus US100l-arabinose isomerase (US100l-AI) was expressed in both LAB, using a new shuttle vector where the araA US100 gene is under the control of the strong and constitutive promoter of the L. bulgaricus ATCC 11842 hlbA gene. The production of L-AI by these LAB allowed the bioconversion of D-galactose to D-tagatose during fermentation in laboratory media and milk. We also established that the addition of L-AI to milk also allowed the conversion of D-galactose into D-tagatose during the fermentation process. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|