The effect of antibiotic treatments on the growth of Pseudomonas stutzeri and Enterobacter gergoviae and the fermentation of several carbohydrates by Enterobacter gergoviae, Enterobacter aerogenes, and Pseudomonas aeruginosa

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Products produced by an agricultural chemical company, bloated in their product containers due to microbial fermentation. Products and their components were tested for the presence of microbes, with Pseudomonas spp. and Enterbacter spp. the most prevalent. The use of preservatives, disinfectants, or antibiotics can be utilized to kill microbes to potentially prevent bloating. Hydrogen peroxide, six antibiotics (Vancomycin, Ampicillin, Doxycline, Ciprofloxacin, Streptomycin, and Gentamicin) and two preservatives (Proxel BN and Proxel GXL) at various concentrations were examined to determine their disinfection efficacy against Pseudomonas stutzeri and Enterobacter gergoviae. The results suggest that hydrogen peroxide, and the two preservatives were effective versus the control at inhibiting microbial growth. The bacteria were susceptible to all but two antibiotics, Vancomycin and Ampicillin. Enterobacter gergoviae, Enterobacter aerogenes, and Pseudomonas aeruginosa, were also examined to access whether they could ferment four separate carbohydrates (xanthan gum, glycerol, propylene glycol, and a red pigment solution) commonly used in products. Each bacterium was tested separately, and each Enterobacter spp. was tested in combination with Pseudomonas aeruginosa. The results suggest that both Enterobacter spp., separately and in combination with Pseudomonas, can ferment glycerol (producing acid and gas), and xanthan (acid only). Enterobacter aerogenes had a higher rate of glycerol fermentation, although not significantly, than Enterobacter gergoviae, and both Enterobacter spp. produced more gas in the presence of Pseudomonas. None of the bacteria could ferment propylene glycol or the red pigment solution. Pseudomonas did not ferment glycerol but may weakly ferment xanthan.