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A total of 119 samples of peanut were collected throughout the peanut production chain in São Paulo State, Brazil. The peanut samples were directly plated for determination of percentages of infection and a polyphasic approach was used to identify Aspergillus section Flavi species. Further, the potential for aflatoxin production by the isolates was tested using the agar plug technique and the presence of aflatoxins in peanuts was assessed using an immunoaffinity column followed by quantification using HPLC with reverse phase column and fluorescence detection. The limit of detection and quantification were 0.05 and 0.17 μg/kg for total aflatoxins, respectively. Four species of Aspergillus section Flavi were isolated: A. caelatus (11), A. flavus (515), A. parasiticus (17) and A. tamarii (13). All isolates of A. parasiticus were able to produce aflatoxin B and G whereas aflatoxin B was produced by 50% of A. flavus isolates. Aflatoxins were found in 12 samples at concentrations ranging from 0.3 to 100 μg/kg. The data reported in this study add information on the occurrence and biodiversity of fungi in peanuts at several stages of the production chain. The occurrence of aflatoxins is also of major relevance for continuous monitoring and assessment of likely exposure of consumers to aflatoxins through consumption of peanuts. [ABSTRACT FROM AUTHOR]

Irrigation water samples were collected from 69 farms in Sao Paulo during two rainy seasons and one dry season. Levels of culturable microorganisms were analyzed using direct plating technique, while levels of E. coli , Enterococci and Clostridium perfringens were determined using membrane filtration. Agroecosystem features including the incidence of manure stockpile, manure lagoon and livestock grazing, amongst others were observed and recorded. In the study area, groundwater (33%) was the most commonly exploited water resource for irrigating vegetables, while the least utilized resources were potable water (4%), streams (2%), lakes (2%) and domestic wastewater (2%). Other water resources exploited for irrigation in the area were farm ponds (21%), harvested rainwater (15%), canals (10%) and rivers (5%). The microbiological quality of water used to irrigate vegetables in the study area was variable depending on factors including source and treatment (chlorination) applied. The levels of culturable microorganisms recovered from the samples ranged between 11.0 and 1.7 log CFU/mL during the rainy and dry seasons, respectively, while the levels of E. coli , Enterococci and Clostridium perfringens detected in irrigation water samples were in the range of 0–6, 0 – 6.5, and 0 – 5.8 log CFU/100 mL, respectively. Irrigation water collected from farms that utilize surface waters such as canals and farm ponds generally contained higher levels of bacteria. In general, bacterial contamination varied among sources in the following order: surface water > groundwater > municipal water. Levels of bacteria detected in groundwater were comparatively low and in about 60% of the cases, for groundwater, no seasonal fluctuation in levels was observed. At the farms where seasonal fluctuations were observed for the levels of bacteria however, at least one potential source of fecal bacteria such as the presence of manure stockpile or livestock grazing was identified. • Groundwater and farm ponds were the main exploited sources for irrigation. • Seasonal variations in levels of indicator bacteria in surface water irrigation. • Irrigation water from farms that used chlorination contained low levels of E. coli. • Cattle grazing influence levels of Enterococci in groundwater irrigation water. • Manure composting is not common amongst studied farms. [ABSTRACT FROM AUTHOR]

Abstract: Minimally processed vegetables (MPV) may be important vehicles of Salmonella spp. and cause disease. This study aimed at detecting and enumerating Salmonella spp. in MPV marketed in the city of São Paulo, Brazil. A total of 512 samples of MPV packages collected in retail stores were tested for Salmonella spp. and total coliforms and Escherichia coli as indication of the hygienic status. Salmonella spp. was detected in four samples, two using the detection method and two using the counting method, where the results were 8.8 × 102 CFU/g and 2.4 × 102 CFU/g. The serovars were Salmonella Typhimurium (three samples) and Salmonella enterica subsp. enterica O:47:z4,z23:- (one sample). Fourteen samples (2.7%) presented counts of E. coli above the maximum limit established by the Brazilian regulation for MPV (102 CFU/g). Therefore, tightened surveillance and effective intervention strategies are necessary in order to address consumers and governments concerns on safety of MPV. [Copyright &y& Elsevier]