Inhibitor of gram-positive bacteria

Rubradirin (70) was isolated from the fermentation broth of Streptomyces achromogenes var. rubradiris [109-114]. Rubradirin (70) possesses pH indicator properties. Namely, it is red in acidic or neutral solutions and green in basic solutions, or in salt form. It is an extremely potent inhibitor of Gram-positive bacteria in vitro, and is effective in the treatment of experimental bacterial infections in mice [114]. The mechanism of the... 

Like lysozyme, nisin is an effective inhibitor of Gram-positive bacteria. Radler (1990a 1990b) determined that most lactic acid bacteria are inhibited by nisin, even in low concentrations, while alcoholic fermentation was not affected. However, the author reported that species varied in their response, with L. casei being the least sensitive. Daeschel et al. (1991) successfully used nisin-resistant strains of O. oeni to conduct MLF in a wine previously treated with nisin to control other spoilage bacteria. Others have reported that nisin killed 100% of O. oeni present as a biofilm on stainless steel (Nel et ak, 2002). Despite its potential, nisin is not currently approved for use in wine in the United States. 

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