Culture conditions affect Lactobacillus reuteri DSM 17938 ability to perform glycerol bioconversion into 3-hydroxypropionic acid.

The platform molecule 3-hydroxypropionic acid (3-HP) can be produced using Lactobacillus reuteri through a two-step bioprocess that involves a growth phase followed by a bioconversion phase. The bioproduction is performed by resting cells that convert glycerol into 3-HP and 1,3-propanediol in fed-batch mode. This work aimed at studying the effect of the growth conditions of L.

Effect of dairy matrices on the survival of Streptococcus thermophilus, Brevibacterium aurantiacum and Hafnia alvei during digestion.

This study evaluated the ability of dairy matrices, different in composition (with and without fat) and structure (liquid and gel), to enhance microorganisms survival through digestion. The viability of three dairy microorganisms Streptococcus thermophilus, Brevibacterium aurantiacum and Hafnia alvei was measured during in vitro and in vivo digestion. S.

Salivary enzymes and exhaled air affect Streptococcus salivarius growth and physiological state in complemented artificial saliva.

To better understand the phenomena governing the establishment of the oral bacterium Streptococcus salivarius in the mouth, the effect of some environmental factors has been studied in complemented artificial saliva, under oral pH and temperature conditions. Three salivary enzymes at physiological concentrations were tested: peroxidase, lysozyme and amylase, as well as injection of exhaled air. Injection of air containing 5% CO2 and 16% O2 induced a deleterious effect on S.

Characterization of Streptococcus salivarius growth and maintenance in artificial saliva.

Aims: To help gain a better understanding of factors influencing the establishment within the oral cavity of Streptococcus salivarius K12, a commensal oral bacterium, we characterized its behaviour in artificial saliva.

Methods And Results: Streptococcus salivarius K12 was grown in artificial saliva complemented with a representative meal, under oral pH and temperature conditions. Exponential growth phase was characterized by a high specific growth rate (2.

Starvation induces physiological changes that act on the cryotolerance of Lactobacillus acidophilus RD758.

The relationship between lactose starvation and cryotolerance was investigated in Lactobacillus acidophilus RD758. Cryotolerance was measured from the acidification activity of cells recovered after 18-h lactose starvation. It was compared to that of nonstarved cells, both of them in a stationary phase and in the same medium.