Two strains of Staphylococcus aureus was inoculated at final concentrations of 103 or 108 cfu ml-1in natural mineral waters (NMWs) and sterile natural mineral waters (SNMWs) with different levels of total dissolved solids (TDS at 180 °C: <50 and >1500 mg l-1) and sterile distilled deionized water (SDDW). The samples were stored at room temperature and examined every day until no recovery of S. aureus was obtained. This study has indicated that, at initial concentration of 103 cfu ml-1, S. aureus can survive for upto 4 days in commercially bottled NMWs with TDS <50 mg l-1 and for upto 14 days in NMWs with TDS >1500 mg l-1. At the initial concentration of 108 cfu ml-1, S. aureus could still be recovered from the water types with TDS <50 mg l-1 at the end of 6 days, and for upto 10 days in NMW types with TDS >1500mg l-1. There were differences in the survival of pathogens among the mineral water samples with different levels of organic solids at different inoculums. Finally, the autochthonous flora has a negative effect on the fate of S. aureus in samples of water examined.
Survival of Staphylococcus aureus in bottled natural mineral water
Vernile, Anna;BENEDUCE, LUCIANO;SPANO, GIUSEPPE;MASSA, SALVATORE
2010-01-01
Abstract
Two strains of Staphylococcus aureus was inoculated at final concentrations of 103 or 108 cfu ml-1in natural mineral waters (NMWs) and sterile natural mineral waters (SNMWs) with different levels of total dissolved solids (TDS at 180 °C: <50 and >1500 mg l-1) and sterile distilled deionized water (SDDW). The samples were stored at room temperature and examined every day until no recovery of S. aureus was obtained. This study has indicated that, at initial concentration of 103 cfu ml-1, S. aureus can survive for upto 4 days in commercially bottled NMWs with TDS <50 mg l-1 and for upto 14 days in NMWs with TDS >1500 mg l-1. At the initial concentration of 108 cfu ml-1, S. aureus could still be recovered from the water types with TDS <50 mg l-1 at the end of 6 days, and for upto 10 days in NMW types with TDS >1500mg l-1. There were differences in the survival of pathogens among the mineral water samples with different levels of organic solids at different inoculums. Finally, the autochthonous flora has a negative effect on the fate of S. aureus in samples of water examined.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
