Two antioxidative lactobacilli strains as promising probiotics.

Area of Science:

• Microbiology
• Probiotics
• Oxidative Stress

Background:

• The intestinal microflora plays a crucial role in maintaining host health.
• Oxidative stress, caused by reactive oxygen species (ROS), can disrupt microbial balance.
• Antioxidative bacteria may offer protective benefits within the gut ecosystem.

Purpose of the Study:

• To isolate and characterize antioxidative bacterial strains from a healthy child's intestinal microflora.
• To evaluate the survival and protective mechanisms of these strains against ROS.
• To assess their potential as probiotics for combating oxidative stress.

Main Methods:

• Isolation of bacterial strains from intestinal microflora.
• Assessment of strain survival under exposure to hydrogen peroxide, superoxide anions, and hydroxyl radicals.
• Quantification of intracellular glutathione and expression of manganese superoxide dismutase (Mn-SOD).
• Evaluation of antimicrobial activity against relevant pathogens.

Main Results:

• Two antioxidative strains, identified as Lactobacillus fermentum E-3 and E-18, were isolated.
• These strains showed significantly increased survival against ROS compared to non-antioxidative strains.
• E-3 and E-18 possess high glutathione levels, express Mn-SOD, and secrete hydrogen peroxide.
• The strains exhibited notable antimicrobial activity.

Conclusions:

• Lactobacillus fermentum strains E-3 and E-18 possess significant antioxidative and antimicrobial capabilities.
• Their ability to withstand oxidative stress suggests a role in protecting the intestinal microbial ecosystem.
• These findings highlight their potential as beneficial probiotics for managing oxidative stress in the gut.