Skip to main content
ARS Home » Plains Area » College Station, Texas » Southern Plains Agricultural Research Center » Food and Feed Safety Research » Research » Publications at this Location » Publication #367108

Research Project: Identification of the Ecological Niches and Development of Intervention Strategies to Reduce Pathogenic Foodborne Pathogens in Poultry

Location: Food and Feed Safety Research

Title: Methylsulfonylmethane exhibits bacteriostatic inhibition of vancomycin resistant Enterococcus faecium, in vitro

item Poole, Toni
item Genovese, Kenneth - Ken

Submitted to: Microbial Drug Resistance
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2020
Publication Date: 1/15/2021
Citation: Poole, T.L., Benjamin, R., Genovese, K.J., Nisbet, D.J. 2021. Methylsulfonylmethane exhibits bacteriostatic inhibition of vancomycin resistant Enterococcus faecium, in vitro. Microbial Drug Resistance. 27(1):13-17.

Interpretive Summary: Bacteria that cause disease (pathogens) in humans and animals have produced serious concerns by public health officials because diseases once thought largely under control are reappearing. Some public health officials blame the food animal industry for the emergence of pathogenic bacteria and downplay the role of human medicine. Enterococci are bacteria that naturally live in the gut of all animals. However, they can cause diseases if a person’s immune system has been weakened for some reason. In a case such as that, Enterococci are called opportunistic pathogens. The most likely place to get this type of infection is in a hospital. Hospitals need new antimicrobials and disinfection methods to treat or prevent infections. Methylsulfonylmethane (MSM) is a nutritional supplement approved for use in humans, horses, and dogs to reduce inflammation caused by arthritis. In this study, we have shown that MSM inhibits Vancomycin Resistant Enterococcus faecium. Vancomycin Resistant Enterococcus faecium is a priority 2 pathogen listed by the World Health Organization. It commonly causes hospital originated (nosocomial) infections that may lead to death.

Technical Abstract: The purpose of this study was to evaluate antibacterial properties of Methylsulfonylmethane (MSM) on Vancomycin Resistant Enterococcus faecium (VRE). Bacterial proliferation was measured spectrophotometrically during growth in Brain Heart Infusion Broth (BHIB) with 0, 3, 5, 7, 10, 12, and 16% MSM. To assess the mechanism of inhibition, VRE was grown overnight with 0-16% MSM and enumerated on unmedicated and medicated (3-16 % MSM) Brain Heart Infusion Agar (BHIA). Viability studies were done to evaluate the impact of 10-16 % MSM on VRE over 7 days. Absorbance data indicated a dose dependent inhibition from 0-7% MSM and no growth in 10-16% MSM. VRE enumerated on unmedicated BHIA from overnight cultures, with 10-16% MSM partially recovered. No growth was observed when BHIA contained 10-16% MSM. There was little effect on VRE growth in 10% MSM over 7 days. VRE displayed a population rebound on day 6 when exposed to 12% MSM and elimination by day 6 in 16% MSM. Regrowth after MSM removal may be indicative of a bacteriostatic mechanism of inhibition. Cell elimination in 16% MSM may suggest inhibition of an essential metabolic function from which the bacterium could not recover.