Lactobacillus AS PRODUCERS OF EXTRACELLULAR TANNASE

Abstract

The aim of the work was to find strains of lactic acid bacteria capable to synthesize extracellular tannase enzyme − the key enzymehe hydrolyzing tannins which are plant food constituent. One of the main product of tannins hydrolyzis is gallic acid- the compound with proven antioxidant and onco-protective properties. As a result of lactobacteria screening, two biocompatible strains of lactic acid, namely L. rhamnosus LB3 and L. delbrueckii subsp. delbrueckii with a high level of enzyme productivity, were selected. The maximum accumulation of tannase, corresponding to 0.031 ± 0.002 U/ml for L. rhamnosus LB3 and 0.03 ± 0.002 U/ml for L. delbrueckii subsp. delbrueckii, was observed after 48 h of cultivation. Both strains showed rapid growth and performance of tannase in MRS medium in the presence of glucose or lactose as a carbon source. It was shown that gallic acid, which was a necessary component of the medium as a target enzyme inducer, did not affect the accumulation of lactobacilli biomass. The selected strains are of interest as producers of a bicomponent probiotic with antioxidant properties and require further investigation.

Keywords

• lactobacillus
• probiotics
• tannase
• antioxidants
• carbon sources.