Helichrysum italicum extract interferes with the production of enterotoxins by Staphylococcus aureus

Aims: The purpose of this work was to evaluate the effect of Helichrysum italicum extract on enterotoxin (A-D) production by Staphylococcus aureus strains. Methods and Results: The production of enterotoxins A-D in the presence or absence of H.italicum diethyl ether extract was estimated in microtiter plates using a reversed passive latex agglutination (SET-RPLA) kit (Oxoid, Basingstoke, UK). The results indicate that, in culture medium, inhibition of staphylococcal growth and enterotoxins appeared with 250-125 mug ml(-1) of the extract. Lower concentrations of the extract (62.5-31.25 mug ml(-1) ) did not affect the final viable count of Staph. aureus but reduced the production of enterotoxins B and C. Conclusions: H. italicum interferes with growth and production of enterotoxins by Staph. aureus. Significance and Impact of the Study: There is considerable interest in the use of natural compounds as alternative methods to control undesirable pathogenic micro-organisms.