Food handlers, an important factor in food quality, may contain bacteria that are able to cause foodborne disease. The present study aimed to research coagulase-negative (CNS) and -positive staphylococci (CPS) in 82 food handlers, analyzing nasal and hand swabs, with identification of 62 CNS (75.6%) and 20 CPS strains (24.4%). Staphylococcal enterotoxins genes were investigated by PCR. In 20 CPS strains, 19 were positive for one or more genes. The percentage of CNS presenting genes for enterotoxins was high (46.8%). Despite of the staphylococcal species, the most common gene was sea (35.4%), followed by seh and sej (29.2%). The detection of new staphylococcal enterotoxins (SEs) genes showed a higher pathogenic potential in this genus. The presence of these gene points out the importance of CNS not only as contaminant bacteria but also as a pathogen.

Propolis shows biological properties such as antibacterial action. This bee product has a complex chemical composition, which depends on the local flora where it is produced. Salmonella serovars are responsible for human diseases that range from localized gastroenteritis to systemic infections. The aim of the present study was to investigate the susceptibility of Salmonella strains, isolated from food and infectious processes, to the antibacterial action of Brazilian and Bulgarian propolis, as well as to determine the behavior of these bacteria, according to the incubation period, in medium plus propolis. Dilution of ethanolic extract of propolis in agar was the used method. Brazilian and Bulgarian propolis showed an antibacterial action against all Salmonella serovars. The minimal inhibitory concentrations (MIC) of propolis were similar, although they were collected in different geographic regions. Salmonella typhimurium, isolated from human infection, was more resistant to propolis than Salmonella enteritidis.

Propolis antibiotic action has been widely investigated. This assay was carried out in order to observe the in vitro antibacterial activity of propolis against Salmonella enteritidis isolated from food and Salmonella typhimurium isolated from human infections. Propolis was collected by Apis mellifera in two regions of Brazil (Mossoró, Rio Grande do Norte State; and Urubici, Santa Catarina State). Both strains survival percentage decreased with time of incubation in Ethanolic Extracts of Propolis (EEP), demonstrating bactericidal effect after 24 hours. It was also observed that EEP from Mossoró was more effective than that from Urubici. The control of the propolis solvent - 70% ethanol - was less effective than EEP, showing only a bacteriostatic effect. We can conclude that propolis shows an activity against Gram-negative bacteria that varies according to the geographical region where it was collected by bees.

This study investigated the antibacterial activity of propolis produced by A. mellifera and Brazilian stingless bees, called "meliponíneos". Susceptibility tests to ethanolic extracts of propolis (EEP) were performed using bacterial strains (Staphylococcus aureus, Enterococcus sp, and Escherichia coli) isolated from human infections. Dilution of EEP in agar (%v/v) was used for determination of minimal inhibitory concentration (MIC). The stingless bee species (and common names) were: Nannotrigona testaceicornis ("Iraí"), Tetragonisca angustula ("Jataí"), Trigona spinipes ("Arapuá"), Scaptotrigona sp ("Tiúba"), Partamona sp ("Cupira"), Melipona scutellaris ("Uruçu"), Melipona sp ("Manduri"), and Melipona mandaçaia ("Mandaçaia"). EEP inhibitory efficiencies according to bacterial strains were: S. aureus - "Cupira" > "Manduri" = A. mellifera > "Uruçu" > "Mandaçaia" > "Iraí" > "Tiúba" > "Jataí" > "Arapuá" = Ethanol; Enterococcus sp - "Cupira" > "Manduri" > A. mellifera > "Mandaçaia" > "Uruçu" > "Tiúba" > "Jataí" > "Arapuá" = Ethanol; E. coli - "Manduri" > "Jataí" > Ethanol > A. mellifera > "Uruçu" > "Cupira" > "Iraí". Propolis produced by "Cupira" and "Manduri" bees showed higher antibacterial activity than A. mellifera.

Susceptibility to several ethanolic extracts of propolis (EEP) concentrations was tested with the population analysis technique in reference strains of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 35218). The results of these tests showed that all bacteria were killed by EEP concentrations approximately equal or higher (2.0% v/v- S. aureus; 10.0% v/v - E. coli) than the respective minimal inhibitory concentrations (MIC). Regarding the susceptibility to propolis, there was a homogeneity of data with the respective time kill curves showing a clear bactericidal effect during 6 to 9 h of exposition.

The in vitro activity of propolis against 118 Staphylococcus aureus, 108 Escherichia coli, 60 Salmonella typhimurium, 50 Candida albicans, 23 Candida parapsilosis, 19 Candida tropicalis and 14 Candida guilliermondii isolated from human infections was studied by the agar dilution method. Among the bacteria, the Gram-negative were the least susceptible organisms showing minimal inhibitory concentration (MIC) for 90% of the strains tested ranging from 22.5 mg/ml - 10,2% V/V to 23.1 mg/ml - 10.5% V/V. The MIC's for Candida ranged from 0.80 mg/ml to > 11 mg/ml (0.40% V/V to > 5.0% V/V), the strains of C. parapsilosis being the least susceptible. The relative order of susceptibility among all isolates, was: S.aureus > C. tropicalis > C. albicans > C. guilliermondii > C. parapsilosis > S. typhimurium > E. coli.