Background: New directions of research on lactic acid bacteria include investigation of metabolic pathways for the
synthesis and/or metabolism of 1,2-propanediol, commonly used in the food and chemical industry, medicine,
pharmacy and cosmetology as well as agriculture. The objective of this study was to compare the capacity of
strains representing three diverse heterofermentative species belonging to the genus
Lactobacillus to
synthesize and/or transform 1,2-PD as well as to suggest new directions of research aimed at commercial use
of this metabolite.
Results: The novel strain of
Lactobacillus buchneri
A KKP 2047p, characterized as exhibiting an unusual trait for
that species in the form of capacity to metabolize 1,2-PD, grew poorly in a medium containing 1,2-PD as a sole
carbon source. The supplementation with glucose facilitated rapid growth of bacteria and use of 1,2-PD for the
synthesis of propionic acid. A similar observation was noted for
Lactobacillus reuteri
. On the other hand,
Lactobacillus diolivorans
effectively metabolized 1,2-PD which was the sole carbon source in the medium, and
the addition of glucose inhibited the synthesis of propionic acid. The experiments also investigated the effect
of cobalamin as a diol dehydratase coenzyme involved in the propionic acid synthesis from 1,2-PD whose
addition promoted the yield of the reaction in the case of all tested strains.
Conclusions: All tested isolates showed the ability to effectively metabolize 1,2-PD (in the presence of cobalamin)
and its conversion to propionic acid, which reveals that investigated bacteria meet the essential requirements of
microorganisms with a potential application.
