Karen Signori Pereira

Transmission of toxoplasmosis (Toxoplasma gondii) by foods.

Protozoan foodborne diseases are generally underrecognized. Toxoplasma gondii is the causative agent of toxoplasmosis, one of the most prevalent parasitic infections to humans and domestic animals. The most likely source of T. gondii occurring through food is the consumption of raw or undercooked meat contaminated with tissue cysts. Sporulated T. gondii oocysts, from the feces of infected cats, present in the environment are a potential source of infection. The ingestion of water contaminated with oocysts and the eating of unwashed raw vegetables or fruits were identified as an important risk factor in most epidemiological studies. This review presents information and data to show the importance of T. gondii transmission by foods.

Transmission of Chagas Disease (American Trypanosomiasis) by Food

In April 2009, the centenary of the discovery of the American trypanosomiasis, or Chagas disease, was celebrated. A hundred years after the discovery, little has been invested in diagnostics and treatment because the disease affects mainly poor people in developing countries. However, some changes in the epidemiology of the disease are of great importance today. Chagas disease transmitted through food is a public health concern in all areas where there is a reservoir of Trypanosoma cruzi in wild animals (e.g., mammals and marsupials) and/or where infected triatomine bugs are in contact with human food source items (especially fruits and vegetables). Recently, several outbreaks of illness related to the ingestion of food contaminated with T. cruzi have been recorded in Brazil, Colombia, and Venezuela.

Survival In Vitro and Virulence of Trypanosoma cruzi in Acai Pulp in Experimental Acute Chagas Disease

Chagas disease is a parasitic infection with high socioeconomic impact throughout Latin America. Although this severe, incurable disease can be transmitted by several routes, oral transmission is currently the most important route in the Amazon Basin. Açaí pulp has nutritional properties and is popular throughout Brazil and abroad. However, this pulp has been associated with microepidemics of acute Chagas disease (ACD) in northern Brazil, where açaí fruit is the main food supplement. In this study, we examined the in vitro survival and in vivo virulence of Trypanosoma cruzi Y strain in açaí pulp. Aliquots of in natura açaí pulp produced in Belém city in the northern Brazilian state of Pará were mixed with 10⁵ trypomastigotes. The samples were incubated at room temperature or at 4 or -20°C for various periods, and the parasites were isolated by forced sieving. The resulting eluates were examined by microscopy, and the trypomastigotes were administered intraperitoneally, orally, or by gavage to immunodeficient mice (C.B-17-Prkdc(scid)/PasUnib) that had been pretreated with antibiotics. Parasitemia was quantified by the Brener method, and mortality was recorded daily. All routes of administration resulted in ACD. A 5-day delay in the onset of parasitemia occurred with oral administration. The survival and virulence of the parasites were unaffected by prior incubation at room temperature for 24 h, at 4°C for 144 h, and at -20°C for 26 h. These results indicate that T. cruzi can survive and retain its virulence in açaí pulp under various conditions and that cooling and freezing are not suitable methods for preventing foodborne ACD.

Identification and molecular phylogeny of coagulase-negative staphylococci isolates from Minas Frescal cheese in southeastern Brazil: Superantigenic toxin production and antibiotic resistance.

Minas Frescal is a typical Brazilian fresh cheese and one of the most popular dairy products in the country. This white soft, semiskimmed, nonripened cheese with high moisture content is obtained by enzymatic coagulation of cow milk using calf rennet or coagulants, usually in industrial dairy plants, but is also manufactured in small farms. Contamination of Minas Frescal by several staphylococci has been frequently reported. Coagulase-negative staphylococci (CNS) strains are maybe the most harmful, as they are able to produce heat-stable enterotoxins with super antigenic activities in food matrices, especially in dairy products such as soft cheeses. The aim of the present study was to investigate the presence of CNS strains in Minas Frescal marketed in southeastern Brazil concerning the risk of staphylococci food poisoning by the consumption of improperly manufactured cheese and the possibility of these food matrices being a reservoir of staphylococcal resistance to antimicrobials. Ten distinct CNS strains were found in 6 cheeses from distinct brands. The most frequent species were Staphylococcus saprophyticus (40%), Staphylococcus xylosus (30%), Staphylococcus sciuri (20%), and Staphylococcus piscifermentans (10%). Three strains were identified to the Staphylococcus genera. Three major species groups composed of 3 refined clusters were grouped by phylogenetic analyses with similarities over to 90%. All CNS strains carried multiple enterotoxin genes, with high incidence of sea and seb (90 and 70%, respectively), followed by sec/see, seh/sei, and sed with intermediate incidence (60, 50, and 40%, respectively), and, finally, seg/selk/selq/selr and selu with the lowest incidence (20 and 10%, respectively). Real-time reverse transcription PCR and ELISA assays confirmed the enteroxigenic character of the CNS strains, which expressed and produced the enterotoxins in vitro. The CNS strains showed multiresistance to antimicrobial agents such as β-lactams, vancomycin, and linezolid, which have therapeutic importance in both human and veterinarian medicines. The risk of staphylococci food poisoning by the consumption of improperly manufactured Minas Frescal was emphasized, in addition to the possibility of these food matrices being a reservoir for antibiotic resistance. More effective control measures concerning the presence and typing of staphylococci in raw milk and dairy derivatives should be included to prevent the spread of pathogenic strains.

Virulence of Trypanosoma cruzi in Açai (Euterpe oleraceae Martius) Pulp following Mild Heat Treatment

Outbreaks of acute Chagas disease (ACD) in northern Brazil can be caused by the ingestion of unprocessed açai pulp contaminated with Trypanosoma cruzi . The aim of this study was to determine the minimum thermal process required to inactivate T. cruzi in açai pulp. Trypomastigotes (100,000) of T. cruzi Y strain were added to 0.15 M NaCl or açai pulp and continuously mixed while being heat treated at 37 to 49°C for up to 1 h. When necessary, parasites were separated from açai pulp by forced sieving. Inocula were administrated intraperitoneally in inbred immunodeficient C.B-17-Prkdcscid/Pas Unib mice, and the recipients were monitored for parasitemia and mortality. Mice received prophylactic antibiotic therapy by using cephalexin to prevent bacterial infection from the açai pulp. T. cruzi retained its virulence in 0.15 M NaCl and açai pulp at 44 ± 0.1°C for 10 min and at 43 ± 0.1°C for 20 min, respectively, causing ACD and death in mice up to 24 days after infection. Incubation of açai pulp inoculum above 43°C for 20 min neutralized T. cruzi virulence, thereby preventing ACD and death in murine recipients. The heating of açai pulp above 43°C for 20 min is a practical and effective measure to prevent foodborne ACD caused by T. cruzi .

FSSC 22000 Packaging Implementation: a Plastics Industry Research

This paper presents the outcomes of an exploratory research carried out in companies, which are located in Brazil. They are FSSC-22000-certified food plastic packaging manufacturers. In order to identify the key aspects of the implementation process and certification, a questionnaire was developed and sent to twenty certified organizations. Out of them, eleven of which participating companies responded in a collaborative way. Based on the data obtained, improving competitiveness and customer retention were the reasons, which led the companies to seek the certification. However, the greatest difficulties were related to personnel, which presented technical and behavioral issues. In addition, it was noted that an overall satisfaction, derived from after-certification benefits, has been arisen in the companies. For instance, enhanced employee awareness, improved company’s image and winning new customers, significantly contributing to their competitiveness, are some of the benefits found in this process.

Salad dressing spoilage by Bacillus amyloliquefaciens with gas formation

B. amyloliquefaciens is a Gram-positive, aerobic, motile rod, often found in soil, which has been described as a plant growth promoter and is used in several industrial processes. This study reports an episode involving the gassy spoilage of salad dressing caused by B. amyloliquefaciens in a production facility located in Rio de Janeiro, Brazil. Nine B. amyloliquefaciens strains were isolated from spoiled salad dressings, the sugar used as a raw material in the manufacture and from the production plant. A genotypic analysis of the isolates by Rep-PCR generated eight band profiles grouped in five Rep-PCR clusters. When re-inoculated into fresh salad dressing three B. amyloliquefaciens isolates belonging to the Rep-PCR clusters A, D and E were able to reproduce the gassy spoilage process, whereas the isolates belonging to the Rep-PCR clusters B and C did not produce any visible spoilage, suggesting that these isolates were not directly involved in the spoilage process. The predominant Rep-PCR cluster, cluster A, included strains isolated from barbecue and passion fruit seed salad dressings and from sugar (raw material), suggesting it is a common source of contamination for such salad dressings.

Microbiological Quality and Safety of Minas Frescal Cheese Commercialized Under Federal Inspection in Rio de Janeiro City, Rj, Brazil

Camilla Pires de Souza, Luis Eduardo Henrique de Freitas Pereira, Karen Signori Pereira. Microbiological Quality and Safety of Minas Frescal Cheese Commercialized Under Federal Inspection in Rio de Janeiro City, RJ, Brazil. In: Anais do 12o Congresso Latinoamericano de Microbiologia e Higiene de Alimentos MICROAL 2014 [= Blucher Food Science Proceedings, num.1, vol.1]. Sao Paulo: Editora Blucher, 2014. DOI 10.5151/foodsci-microal-203 Microbiological Quality and Safety of Minas Frescal Cheese Commercialized Under Federal Inspection in Rio de Janeiro City, RJ, Brazil