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Pseudomonas aeruginosa is a Gram-negative bacillus associated with waterborne diseases. The objective of this study was to determine whether particular P. aeruginosa sequence types (STs) were associated with drinking water contamination in Brazil. This was achieved by searching the Pseudomonas PubMLST database, which contains the records for 8358 strains collected between 1938 and 2023. The majority (97.2%) had the complete 7-loci multilocus sequence typing profile and were assigned to 3486 STs. After eBURST (an algorithm used to infer patterns of evolutionary descent among clusters), 1219 groups with single-locus variant and 575 groups with double-locus variant were formed. Brazil was the South American country with the most isolates (n  = 219, 58.24%), and the Simpson's index was 0.9392. Of the 219 Brazilian isolates, eight were isolated in water and identified as STs 252, 1417, 1605, 2502, 2620, 3078, and 3312. ST252, 1417, and 3078 have already been isolated from clinical cases worldwide. Furthermore, ST1605 and 2620, after the eBURST, they were grouped in the same clonal complex as STs involved in human infections. In conclusion, P. aeruginosa STs involved in human infections were found in bottled drinking water commercialized in Brazil, revealing that these types of drinking waters can be a vehicle of contamination. [ABSTRACT FROM AUTHOR]

We evaluated the combined effects of vacuumed hydrogen peroxide vapour (VHPV) and vacuum‐sealed dry heat (vacuum heat, VH) to inactivate food‐borne pathogens (Salmonella Typhimurium, Escherichia coli O157:H7 and Listeria monocytogenes) on alfalfa seeds. Alfalfa seeds inoculated with food‐borne pathogens were sequentially treated initially with 1·0 ml of 0 or 30% VHPV for 1 min and later with dry heat (DH) or VH for 2 h, and the rate of seed germination was evaluated. The combination treatment decreased the populations of three food‐borne pathogens below the limit of detection (1·0 log CFU per gram) on alfalfa seeds without decreasing germinability. The sequential treatment using VHPV and VH greatly reduced the total treatment time needed to inactivate pathogens on alfalfa seeds by more than 5 log CFU per gram. These results demonstrate that a combination of VHPV and VH has potentially employed as a new method for pasteurization of alfalfa seeds without affecting their germinability. [ABSTRACT FROM AUTHOR]

Controlling spread of human pathogens on fresh produce is a top priority for public health reasons. Isolation of compounds from agricultural waste that would control spread of human pathogens was explored using Salmonella enterica serovar Typhimurium as a model organism. In the environment, micro-organisms migrate as a 'community' especially when they move on moist surfaces. This type of motility is characterized as swarming motility. We examined extracts from agricultural waste such as soya bean husk, peels of orange, pineapple, avocado and pomegranate for antiswarming activity. Avocado and pineapple peels showed moderate (~40%) inhibition of swarming motility while pomegranate peel extract had high antiswarming activity (~85% inhibition) and was examined in further detail. Although the pomegranate peel extract was acidic, swarm-inhibitory activity was not due to low pH and the peel extract did not inhibit growth of Salmonella. Among the key swarm motility regulatory genes, class II ( fliF, fliA, fliT and fliZ) and class III ( fliC and fliM) regulators were downregulated upon exposure to pomegranate peel extract. Pomegranate peels offer great potential as a bioactive repellent for pathogenic micro-organisms on moist surfaces. Significance and Impact of the Study Controlling the spread of food-borne pathogens in moist environments is an important microbial food safety issue. Isolation of compounds from agricultural waste (such as fruit peels) that would control spread of human pathogens was explored using Salmonella enterica serovar Typhimurium as a model organism. Pomegranate peels offer great potential as a bioactive repellent for pathogenic micro-organisms. [ABSTRACT FROM AUTHOR]

The distribution and presence of hygiene indicator and pathogenic micro-organisms in 375 samples of attieke marketed in Côte d' Ivoire, and their roles in the food poisoning were evaluated. Microbiological analyses were carried out, which included the total viable bacteria, coliforms, Escherichia coli, Staphylococcus aureus, Salmonella, Bacillus spores, fungi and Clostridium perfringens. The results revealed that the viable bacteria counts ranged from 2·2 ± 1·2 × 105 to 3·4 ± 1·4 × 106 CFU g−1, while the yeasts and the moulds counts ranged, respectively, from 2·4 ± 0·12 × 104 to 9·8 ± 0·4 × 105 CFU g−1 and 1·3 ± 0·7 × 101 to 1·7 ± 0·7 × 102 CFU g−1. Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Citrobacter freundi, Enterobacter amnigenus, Citrobacter youngae, Enterobacter aerogenes, Klebsiella pneumoniae, Serratia marcescens, Enterobacter agglomerans and Klebsiella oxytoca were the bacteria isolated, and Rhizopus spp., Mucor spp., Thamnidium spp., Fusarium spp., Moniliella spp. the fungi. Escherichia coli, Clostridium perfringens and Salmonella spp. were not found. The occurrence of some bacteria and fungi illustrate that attieke collected in Côte d'Ivoire markets may act as a reservoir of pathogenic micro-organisms for human. Significance and Impact of Study This study demonstrates the great need to carry out microbiological tests frequently on attieke and even more the need to apply correct HACCP system during the production. Attieke is especially a well-known product in West Africa; hence, it is extremely important to ensure an adequate microbiological quality to guarantee consumers health. Overall, the study highlighted the need for effective communication on microbiological food risks, proper instruction and supervision in food-handling procedures, greater education on food safety risks. [ABSTRACT FROM AUTHOR]

t.l. wong, g.v. carey-smith, l. hollis and j.a. hudson. 2005. To gauge the effectiveness of pâté and ham manufacturers’ management of the microbial safety and quality of their products. A survey of 60 batches of prepackaged pâté showed that 41·7% of the batches had aerobic plate counts (APC) exceeding 105 CFU g−1, one of pâté sample contained a Bacillus cereus count of >5000 CFU g−1 and another contained 1700 CFU g−1 of Listeria monocytogenes. No other pathogens were isolated from any of the samples. The survey of prepackaged ham showed that only 1% (1/104) of the ham samples were positive for L. monocytogenes (50 CFU g−1). The presence of microbial hazards in these foods has generally declined since the early 1990s in New Zealand. Noncomplying APC levels may be due to an over-estimation of product shelf life or poor food handling practices during manufacture. Few of the samples tested contained pathogens at significant levels. The prevalences of L. monocytogenes in pâté and ham were low. The presence of 1700 CFU g−1 of L. monocytogenes in a pâté sample indicates that occasionally, the population can be exposed to levels of L. monocytogenes above the zero tolerance level set in New Zealand. [ABSTRACT FROM AUTHOR]

y.s. jung, r.c. anderson, t.r. callaway, t.s. edrington, k.j. genovese, r.b. harvey, t.l. poole and d.j. nisbet. 2004.To test the inhibitory activity of 2-nitro-1-propanol (2NPOH) againstSalmonellaTyphimurium,Escherichia coliO157:H7 andEnterococcus faecalis.Specific growth rates (h−1) ofS. Typhimurium,E. coliO157:H7 andEnt. faecaliswere determined during culture in tryptic soya broth (TSB) supplemented with 0–10 mm2NPOH. Growth rates were inhibited by 2NPOH, with nearly complete inhibition observed with 10 mm. Studies withS. Typhimurium revealed that its survivability during culture in TSB containing 5 or 10 mm2NPOH was lower (P < 0·05) under aerobic than anaerobic conditions. The survivability ofSalmonelladuring anaerobic culture in TSB containing 2·5 mm2NPOH was less at pH 5·6 than at pH 7·0 and 8·0. NoSalmonellasurvived anaerobic incubation in TSB supplemented with 10 mm2NPOH regardless of pH. When incubated in suspensions of freshly collected populations of ruminal and faecal bacteria,Salmonellaconcentrations were lower (P < 0·05) in suspensions containing 10 mm2NPOH than in suspensions containing no 2NPOH.2NPOH inhibitedS. Typhimurium,E. coliO157:H7 andEnt. faecalis.Results suggest that 2NPOH may be a useful antimicrobial supplement to reduce carriage of certain food-borne pathogens in food animals. [ABSTRACT FROM AUTHOR]