Reuterin

Reuterin is a neutral broad-spectrum antimicrobial substance formed during anaerobic growth of Lactobacillus reuteri in the presence of glycerol (Axelsson et al., 1989). Reuterin is an equilibrium mixture of monomeric, hydrated monomeric, and cyclic dimeric forms of (Vhydroxypropionalde-hyde. The inhibitory effect of reuterin has been associated with its action on DNA synthesis by acting as an inhibitor of the substrate binding subunit of ribonucleotide reductase. 

El- Ziney, M.G., van den Tempel, T., Debevere, J., and Jakobsen, M. 1999. Application of reuterin produced by Lactobacillus reuteri 12002 for meat decontamination and preservation. J. Food Prot. 62, 257-261. 

Organic acids (lactic, acetic) Bacteriocins co2 Hydrogen peroxide Diacetyl Reuterin Ethanol Increase acidity, antimicrobial compounds Nisin only bacteriocin permitted as food preservative, disrupts cytoplasmic membrane Reduces membrane permeability Oxidizes proteins Interacts with arginine-binding proteins Not confirmed, may interact with thiol group in proteins that may lead to oxidative stress (Whitehead et al., 2008)... 

LAB produce several compounds with antimicrobial properties as a result of nutrient competition with other microorganisms growing in the same niche. These antimicrobial active metabolites consist of nonspecific antimicrobial substances such as short-chain fatty acids (formic, acetic, propionic, butyric, and lactic acids), ethanol and hydrogen peroxide, and toxins including bacteri-ocins (nisin, reuterin, reutericyclin, pediocin, lacticin, enterocin, and others). 

Martin, R., Olivares, M., Marin, M.L., Xaus, J. et al. (2005) Characterization of a reuterin-producing Lactobacillus coryniformis strain isolated from a goat s milk cheese. Int. J. Food Microbiol, 104, 267-277. 

Scientific research has also suggested that this inhibitory activity of LAB over molds may result from the production of metabolites such as organic acids (in particular, lactic, propionic, and acetic acids), carbon dioxide, ethanol, hydrogen peroxide, diacetyl, reuterin, and other small molecular weight metabolites production of proteinaceous compounds or low-molecular weight peptides competitive growth decrease in the pH caused by acid production or a combination of these factors (Bianchini BuUerman, 2010). 

Chung, T. C., Axelsson, L., Lindgren, S. E., Dobrogosz, W. J. (1989). In vitro studies on reuterin synthesis by Lactobacillus reuteri. Microbial Ecology in Health and Disease, 2, 137-144. 

Nakanishi, K., Tokuda, H., Ando, T., Yajima, M., Nakajima, T., Tanaka, O., et al. (2002). Screening of lactic acid bacteria having the ability to produce reuterin. Japanese Journal of Lactic Acid Bacteria, 13, 37-45. 

Rasch M. (2002). The influence of temperature, salt and pH on the inhibitory effect of reuterin on Escherichia coli. Int J Food Microbiol, 72, 225-231. 

Talarico TD, Casas lA, Chung TC, Dohrogosz WJ. (1988). Production and isolation of reuterin, a growth inhibitor produced by Lactobacillus reuteri. Antimicrob Agents Chemother, 32, 1854-1858. 

Reuterin is a broad-spectrum antimicrobial substance produced by Lactobacillus reuteri (Axelsson etal., 1989). Reuterin is 3-hydroxypropion-aldehyde (3-HPA). It is effective against bacteria, yeasts, moulds, protozoa and viruses. 

Arques, J.L., Rodriguez, E., Nunez, M., and Medina, M. 2008. Inactivation of Gram-negative pathogens in refrigerated milk by reuterin in combination with nisin or the lactoperoxidase system. European Food Research and Technology, 227(1), 77-82. 

Morita, H., Toh, H., Fukuda, S., et al. (2008). Comparative genome analysis of Lactobacillus reuteri and Lactobacillus fermentum reveal a genomic island for reuterin and cobalamin production. DNA Res 15,151-161. 

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