ISOLATION OF COAGULASE NEGATIVE STAPHYLOCOCCUS STRAINS FROM FOODS OF ANIMAL ORIGIN EXIBITING ENTEROGENECITY AND ANTIBIOTIC RESISTANCE
NUNES, R.S.C.1 *, PEREIRA, K.S.2, DEL AGUILA, E.M1 and PASCHOALIN,V.M.F.1
1Universidade Federal do Rio de Janeiro, Instituto de Química
2Universidade Federal do Rio de Janeiro, Escola de Química
Staphylococcus is a Gram-positive bacteria which can cause food poisoning and other diseases. Several researchers have reported the existence of coagulase-negative staphylococci (CNS) in food that are able to produce enterotoxins and show antimicrobial resistance.In Brazil, staphylococcal poisoning is the second most common foodborne diseases.Sixty five bacterial CNS strains were isolated from salami (38/65) and cheese (27/65), according to the methodology described in Bergey’s Manualof Systematic Bacteriology and the isolates were identified by sequencing. The 16 enterotoxin genes (sea, seb, sec, sed, see, seg, seh, sei, sej, sem, sen, seo, seq, ser, sek, and seu) were searched within the genome of CNS presumptive strains by multiplex PCR and the antimicrobial susceptibility to antibiotics were tested by using the disc diffusion method. The results showed prevalence of 10 genes in 45 strains of the 65 isolates (45/65): sea (n= 13), sed and see (n= 9), seh (n=7), sem (n= 5), seb (n= 4), sei and sej (n=3), sec and seq (n= 2). In thirty strains (40 %) showed to be reactive against pool antibodies to enterotoxins (sea, seb, sec, sed and see). The 65 isolates were identified as S. sciuri (n=2), S. saprophytics (n=34), S. xylosus (n=3), S. epidermides (n=2) and S. piscifermentas (n=6), S. carnosu s (n=6), S. succinu s (n=2) and Staphylococcus spp. (n=10). The higher resistance of the 65 CNSisolates was observed against penicillin G (50/65, 78%), oxacillin (49/65, 77%), neomicin (37/65, 57%), trimetropim (36/65, 55%), clindamycin (35/65, 54%), gentamicin (34/65, 53%), cefetoxin (33/65, 52%), rifampicin (29/65, 45%), eritromycin (27/65, 42%) and (24/65, 38%) against tetracylcline, vancomycin, ciprofluoxacin, sulfazothrim and cefepime. Taken toghether, the results indicate that the coagulase negative Staphylococcus strains found in cheese and salami showed a high frequency of presence of enterotoxins genes and high antimicrobial resistance to the antibiotics tested.
Financial Support: FAPERJ, CNPq and CAPES; Area: Food Science.
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