A bioluminescent test system reveals valuable antioxidant properties of lactobacillus strains from human microbiota

Abstract

Oxidative stress cause serious damages in human organism resulting in multiple diseases. Antioxidant therapy includes diet, the use of chemical agents or commensal bacteria such as lactobacilli. This study aims to evaluate the antioxidant (AO) activity of cell-free culture supernatants of lactobacilli, isolated from different parts of the human body. A test system based on Escherichia coli MG1655 strains carrying plasmids encoding luminescent biosensors pSoxS-lux and pKatG-lux inducible by superoxide anion and hydrogen peroxide, respectively, was used to analyze cell-free culture supernatants of lactobacilli. Bioluminescent detection systems are suitable for quick screening of AO activity of lactobacilli. The majority of strains (51 out of 81) belonging to six different species demonstrated various levels of antioxidant activity. This activity was confirmed using the trolox equivalent method. The genome of one of the strains showing high AO activity was sequenced, and the genes putatively involved in AO capacity were determined. Potencies of standard AO and CFS from the most active Lactobacillus strains. Percentages of decrease in the detected luminescence (IAO%) in the presence of AO or CFS are presented. L. br.-L. brevis, L. pl. -L. plantarum, L. rh.-L. rhamnosus.

The Lactobacillus brevis 47 f Strain Protects the Murine Intestine from Enteropathy Induced by 5-Fluorouracil

“…The antioxidant properties of L. brevis 47 f strain isolated from the healthy individual has been characterized in cell-free culture supernatants; also, the antioxidant genes have been identified in its genome [ 9 ]. In this study we analyzed in vivo the anti-mucositis efficacy of L. brevis 47 f strain, in the murine model of acute mucositis evoked by i.p.…”

“…Many lactobacilli display antioxidant activity that has been determined in bacterial cultures and in animal models. This activity can be found in living as well as in heat-inactivated bacteria, in cell free extracts and in culture supernatants, indicating that individual cell components and metabolites can have antioxidative properties [ 6 , 8 ] Furthermore, lactobacilli produce a number of biologically active compounds such as peptides, short chain fatty acids, microRNAs, and lipoteichoic acid [ 9 , 10 , 11 ], thereby activating the antioxidant enzymes such as catalase, superoxide dismutase, and glutathione peroxidase via Nrf2-Keap1-ARE-, nuclear factor kappa B (NFκB)-, and mitogen-activated protein kinase/protein kinase C pathways [ 12 , 13 ]. The antioxidant properties, together with immunostimulatory and metabolic activities, and antagonism against pathogenic microorganisms, make lactobacilli attractive therapeutic tools in clinical situations.…”

“…Lactobacilli have recently emerged as a natural component of treatment in ulcerative colitis and inflammatory bowel syndrome [ 14 , 15 ]. In a broader sense, the link between the microbiota and cancer development and treatment is being established [ 9 , 16 , 17 , 18 ]. Indeed, the probiotic strains have demonstrated the ability to attenuate oxidative stress [ 19 ], thereby proving the principle of applicability for the combinations in cancer treatment regimens [ 20 , 21 , 22 , 23 ].…”

“…Earlier we have investigated the antioxidant properties of the culture medium conditioned by lactobacilli strains (total 81 strain) in a luminescent test system based on the genetically engineered strain Escherichia coli K12 MG1655 [ 9 ]. In this strain the hybrid plasmids containing a luciferase operon of Photorhabdus luminescens are regulated by inducible promoter regions of catalase and superoxide dismutase genes.…”

“…The antioxidant capacity (Trolox equivalent) of L. brevis 47 f cell-free supernatant was 1.87, a value double the respective value for glutathione. Genes involved in metabolism of the antioxidant proteins glutathione and thioredoxin have been detected in L. brevis 47 f genome [ 9 ]. In this study we investigated the ability of L. brevis 47 f to protect the murine intestine from 5 FU induced mucositis.…”