Influence of sodium chlorate, ferulic acid, and essential oils on Escherichia coli and porcine fecal microbiota

Authors: ARZOLA-ALVAREZ, CLAUDIO - Universidad Autonoma De Chihuahua; Hume, Michael; Anderson, Robin; LATHAM, ELIZABETH - Bezoar Laboratories Llc; RUIZ-BARRERA, OSCAR - Universidad Autonoma De Chihuahua; CASTILLO-CASTILLO, YAMICELA - Universidad Autonoma De Chihuahua; OLIVAS-PALACIOS, ANA - Universidad Autonoma De Chihuahua; FELIX-PORTILLO, MONSERRATH - Universidad Autonoma De Chihuahua; ARMENDARIZ-RIVAS, RUTH - Universidad Autonoma De Chihuahua; ARZOLA-RUBIO, ALEJANDRO - Universidad Autonoma De Chihuahua; ONTIVEROS-MAGADAN, MARINA - Universidad Autonoma De Chihuahua; BAUTISTA-MARTINEZ, YURIDIA - Bezoar Laboratories Llc; SALINAS-CHAVIRA, JAIMIE - University Of Tamaulipas

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/14/2020
Publication Date: 2/17/2020
Citation: Arzola-Alvarez, C., Hume, M.E., Anderson, R.C., Latham, E.A., Ruiz-Barrera, O., Castillo-Castillo, Y., Olivas-Palacios, A.L., Felix-Portillo, M., Armendariz-Rivas, R.L., Arzola-Rubio, A., Ontiveros-Magadan, M., Bautista-Martinez, Y., Salinas-Chavira, J. 2020. Influence of sodium chlorate, ferulic acid, and essential oils on Escherichia coli and porcine fecal microbiota. Journal of Animal Science. 98(3). Article skaa059. https://doi.org/10.1093/jas/skaa059.
DOI: https://doi.org/10.1093/jas/skaa059

Interpretive Summary: The influence of sodium chlorate (SC), ferulic acid (FA), and essential oils (EO) was examined on two pig Escherichia coli pathogens, F18 and K88, and populations of normal beneficial nonpathogenic pig fecal bacteria. Bacterial populations were examined by two DNA molecular techniques, denaturing gradient gel electrophoresis (DGGE), and bacterial identification by sequencing characteristic genes. The treatments were control (no additives), SC, FA, EO (a commercial blend of oregano oil, cinnamon oil, water and citric acid), and mixtures of EO+SC, EO+FA and FA+SC. Freshly collected pig feces mixed into nutrient broth was inoculated with E. coli F18 or E. coli K88 for culturing. Culture samples were taken at 0, 6, and 24 h of incubation for enumeration of E. coli and extraction of DNA. All treatments reduced E. coli F18 numbers at 6 and 24 h. With the exception of SC, all treatments reduced K88 numbers at 24 h. Treatments containing EO were the most effective in reducing F18 and K88 numbers. Results from DGGE revealed that fecal bacterial populations in all samples over all times were similar to those of the controls given no treatment. The results from gene sequencing showed that, except for SC at 24 h, potential beneficial bacterial numbers increased, and potential harmful bacteria numbers decreased. In conclusion, all treatments were effective in reducing the E. coli pathogens, with EO being the most effective. The beneficial pig bacterial communities were not greatly influenced by the treatments. Results are of interest to livestock researchers and producers seeking alternatives to antibiotics against pathogens potentially harmful to consumers of meat products.

Technical Abstract: The influence of sodium chlorate, ferulic acid, and essential oils was examined on the survivability of two porcine diarrhetic enterotoxigenic Escherichia coli (ETEC) strains (F18 and K88) and populations of normal beneficial nonpathogenic porcine fecal bacteria. Fecal bacterial populations were examined by denaturing gradient gel electrophoresis (DGGE) and identified by 16S gene sequencing. The treatments were control (no additives), 10 mM sodium chlorate (SC), 2.5 mg ferulic acid/mL (FA), a 1.5% vol/vol solution of an essential oils mixture (EO), as well as mixtures of EO+SC, EO+FA, and FA+SC at each of the aforementioned concentrations. Essential oils were a commercial blend of oregano oil and cinnamon oil with water and citric acid. Freshly collected porcine feces (0.5%, wt/vol) in 300 mL of Mueller Hinton broth was inoculated with approximately 10**6 CFU of E. coli F18 (Trial 1) or E. coli K88 (Trial 2). Ten-milliliter volumes of the fecal-E. coli suspensions were transferred to 18 x 150 mm crimp top tubes preloaded with less than or equal to 0.3 mL of stock concentrations of the treatment compounds. Quantitative enumeration was at 0, 6, and 24 h. All treatments reduced (P less than 0.05) the counts of E. coli F18 at 6 and 24 h. With the exception of SC, all the other treatments reduced (P less than 0.05) the K88 counts at 24 h. The most effective treatments to reduce the F18 and K88 growth were those containing EO. Results of DGGE revealed that Dice percentage similarity coefficients (%SC) of bacterial profiles among treatment groups varied from 81.3 to 100%SC. The results of gene sequencing showed that, except for sodium chlorate at 24 h, all other treatments reduced the counts of the family Enterobacteriaceae, while Lactobacillaceae and Ruminococcaceae increased, and Clostridiaceae decreased in all treatments. In conclusion, all treatments were effective in reducing the ETEC, but EO was the most effective. There were no synergic effects when treatments were combined. The porcine microbial communities may be influenced by the studied treatments.