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ARS Home » Midwest Area » Peoria, Illinois » National Center for Agricultural Utilization Research » Renewable Product Technology Research » Research » Publications at this Location » Publication #311530
Title: Fate of virginiamycin through the fuel ethanol production process

Author
item Bischoff, Kenneth
item ZHANG, YANHONG - Southern Illinois University
item Rich, Joseph

Submitted to: World Journal of Microbiology and Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/7/2016
Publication Date: 4/2/2016
Citation: Bischoff, K.M., Zhang, Y., Rich, J.O. 2016. Fate of virginiamycin through the fuel ethanol production process. World Journal of Microbiology and Biotechnology. 32(5):76. doi: 10.1007/s11274-016-2026-3.

Interpretive Summary: This research demonstrated that an antibiotic commonly used to control bacterial contamination during fuel ethanol production may persist in an active form in the distiller’s grains coproducts. Antibiotics are frequently used to prevent and treat bacterial contamination of commercial fuel ethanol fermentations, but there is concern that antibiotic residues may persist in the distiller’s grains coproducts. Using pilot plant facilities to mimic the commercial process, this work found biologically active antibiotic in distillers grains produced from an ethanol fermentation that was treated with the antibiotic virginiamycin. This information is important to fuel ethanol producers, the animal feed industry, and regulatory agencies that seek to control bacterial contamination in commercial fermentation cultures while minimizing antibiotic residues that can select for antibiotic resistant microorganisms.

Technical Abstract: Antibiotics are frequently used to prevent and treat bacterial contamination of commercial fuel ethanol fermentations, but there is concern that antibiotic residues may persist in the distillers grains coproducts. A study to evaluate the fate of virginiamycin during the ethanol production process was conducted in the pilot plant facilities at the National Corn to Ethanol Research Center, Edwardsville, IL. Three 4,000 gallon fermentor runs were performed: one with no antibiotic (F1), one dosed with 2 parts per million (ppm) of a commercial virginiamycin product (F2), and one dosed at 20 ppm of virginiamycin product (F3). Fermentor samples, distillers grains (DDGS), and process intermediates (whole stillage, thin stillage, syrup, and wet cake) were collected from each run and analyzed for virginiamycin M and virginiamycin S using a liquid chromatography/mass spectrometry method. Virginiamycin M was detected in all process intermediates of the F3 run. On a dry-weight basis, virginiamycin M concentrations decreased approximately 97%, from 41 'g/g in the fermentor to 1.4 'g/g in the DDGS. Using a disc plate bioassay, antibiotic activity was detected in DDGS from both the F2 and F3 runs, with values of 0.69 'g virginiamycin/g sample and 8.9 'g/g, respectively. No antibiotic activity (< 0.6 'g/g) was detected in any of the F1 samples or in the fermentor and process intermediate samples from the F2 run. These results demonstrate that low concentrations of biologically active antibiotic may persist in distiller’s grains coproducts produced from fermentations treated with virginiamycin.