Abstract
Goat milk has been frequently implicated in staphylococcal food poisoning. The potential risk of raw goat milk contaminated by Staphylococcus aureus (S. aureus) in Shaanxi province of China is still not well documented. This study investigated the prevalence, antibiotic resistance, as well as virulence-related genes of S. aureus from raw goat milk samples in Shaanxi, China. A total of 68 S. aureus isolates were cultured from 289 raw goat milk. Most of the isolates were resistant to penicillin and oxacillin, although 41.18%, 33.82%, and 29.41% of the isolates expressed resistance to piperacillin, trimethoprim-sulfamethoxazole, and ciprofloxacin, respectively. Our data demonstrated that 91.18% of the isolates produced biofilm, of which 54.41% isolates belonged to high-biofilm producers. In addition, genotypic analysis of biofilm related genes (fnbA, clfB, fnbB, cna) revealed that 91.18% of the isolates harbored at least one of the genes, in which the most prevalent genes were fnbA (66. 17%), clfB (48.53%), and fnbB (26.47%). 94.8% of the isolates contained at least one toxin-related gene, of which seb (76.47%), tsst (36.76%), and sea (23.53%) genes were the more frequently detected. Further analysis revealed a positive association between fnbA, clfB, fnbB, seb, tsst, and sea genes and certain antibiotic resistance. The results indicated that raw goat milk samples contaminated by S. aureus can be a potential risk to public health.
Highlights
Staphylococcus aureus (S. aureus) is a Gram-positive pathogen that can be isolated from a wide range of food, animal, human, and medical environments
S. aureus counts ranged from 2.6 × 102 to 3.3 × 104 CFU/mL, with a mean value of 5.6 × 103 CFU/mL, in which 25 isolates were lower than 103 CFU/mL and 43 isolates were more than 103 CFU/mL, suggesting the existence of factors associated with the S. aureus in raw goat milk produced in the region
Our study provides an epidemiological investigation of the prevalence of S. aureus in raw goat milk in Shaanxi province, China
Summary
Staphylococcus aureus (S. aureus) is a Gram-positive pathogen that can be isolated from a wide range of food, animal, human, and medical environments. Microbial food poisoning accounted for 53.7% of the food poisoning incidents in China, of which S. aureus is one of the most commonly identified foodborne pathogens that causes a wide range of clinical infections [1]. A biofilm is defined as an assemblage of microbial cells that irreversibly attaches to a surface and enclosed in a matrix of hydrated extracellular polymeric substances [10]. Biofilm development of S. aureus consists of a three-stage process of deeply wired genetic developmental process triggered by stress signals, including (i) attachment of cells to surface, (ii) maturation of the biofilm, and (iii) detachment/dispersal [11,12]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have