Electrolyzed Water Kills Bad Bacteria While Sparing Good Gut Microbes

Authors
Journal
Environmental Microbiology
Year
DOI
10.1111/1462-2920.70337
Study Type
Cell Culture
Outcome
Positive
Peer Reviewed
Yes
Country
China
Health Condition
Microbial Infections
Body System
Digestive

TL;DR

Slightly acidic electrolyzed water selectively eliminated Salmonella enteritidis while allowing partial survival and recovery of beneficial Lactobacillus plantarum, and it improved microbial balance and acidification in silage fermentation.

Key Finding

Slightly acidic electrolyzed water at 70 mg/L chlorine concentration completely eliminated Salmonella enteritidis while allowing over 40% of beneficial Lactobacillus plantarum to survive, demonstrating selective antimicrobial activity based on bacterial cell wall structure.

Summary

Researchers tested slightly acidic electrolyzed water (SAEW)—a disinfectant created by passing electricity through salt water—to see if it could kill harmful bacteria while preserving beneficial bacteria used in fermentation. They found that at certain concentrations, SAEW eliminated dangerous Salmonella bacteria while allowing beneficial Lactobacillus bacteria to survive, likely because the harmful bacteria had weaker cell walls and fewer protective defenses. When tested on fermented plant material, SAEW successfully reduced unwanted microbes while boosting beneficial bacteria populations.

Practical Takeaway

This laboratory study suggests SAEW may have potential as a targeted disinfectant for fermentation systems, but the research was conducted in controlled cell cultures and on plant material, not in human studies. More research would be needed to understand any relevance to hydrogen water products or human health applications.

Abstract

Microbial contamination in fermentation systems poses significant risks to safety and efficiency, as harmful microbes can proliferate while conventional disinfectants often indiscriminately harm beneficial lactic acid bacteria (LAB). This study investigated the selective antimicrobial activity of slightly acidic electrolyzed water (SAEW) against Salmonella enteritidis (S. enteritidis) and Lactobacillus plantarum (L. plantarum) using monoculture, co-culture and mechanistic analyses. Selectivity was dependent on available chlorine concentration (ACC): at 70 mg/L, S. enteritidis was completely eliminated, while > 40% of L. plantarum survived. In co-culture, 57.7% of L. plantarum remained viable and recovered, whereas S. enteritidis showed no regrowth. Mechanistic analysis revealed that S. enteritidis was more susceptible due to its thinner cell walls and weaker antioxidant defenses, in contrast to L. plantarum's thicker peptidoglycan layer and robust stress response, which provided partial resistance. To validate these findings in a practical fermentation context, SAEW was applied to Pennisetum sinese silage, where it suppressed undesirable microbes such as Enterobacter and Clostridium lachnoclostridium, enriched LAB populations and enhanced acidification. These results demonstrate SAEW as a residue-free agent for targeted pathogen control and microbial community modulation in fermentation environments.