Occurrence and antimicrobial resistance of bacteria in retail market spices

Abstract

ABSTRACT: This study aimed to evaluate the microbiological quality and the transmission of multidrug-resistant bacteria in different spices sold in town fairs (local food markets) in the municipalities of Recôncavo Baiano. Samples of black pepper, oregano, and cinnamon were collected over a period of six months and investigated for coliforms at 45 °C, Staphylococcus spp., Staphylococcus aureus, Bacillus spp., Bacillus cereus, Escherichia coli and Salmonella spp. The contamination in the black pepper samples (log 4.66 CFU g-1) was higher (P>0.05), than those of cinnamon (log 2.55 CFU g-1) and oregano (log 2.49 CFU g-1), particularly for B. cereus. E. coli (89%) and Salmonella spp. (67%) were isolated only from black pepper. B. cereus and S. aureus showed greater resistance to β-lactams (penicillin, oxacillin, and cefepime), with approximately 40% of the strains with a multiple antimicrobial resistance (MAR) index of 0.33 (i.e., resistant to three antimicrobials). E. coli was more resistant to ampicillin and Salmonella spp. to nalidixic acid, ampicillin, and ceftriaxone. Salmonella spp. had a MAR index ranging from 0.16 to 0.91 (i.e, resistant to up to 11 antimicrobials), and E. coli to up to 0.58 (i.e., resistant to 7 antimicrobials). In conclusion, the spices sold in the town fairs of Recôncavo Baiano are of low microbiological quality, with the presence of pathogens, of which some display high resistance to antimicrobials that are commonly used for treating foodborne illnesses.

Keywords

• spice plants
• antibacterial activity
• multiresistance