Research Publications (Food Safety)

Persistence of Salmonella in milk powders has caused several foodborne outbreaks. The determination of proper pasteurization processing conditions requires an understanding of the thermal inactivation kinetics of Salmonella in milk powders. However, there is a lack of knowledge related to the effects of water activity (aw) and fat content on Salmonella inactivation in milk powder during thermal processing.

ABSTRACT

Author(s): Elena Bartkiene, Modestas Ruzauskas, Vadims Bartkevics, Iveta Pugajeva, Paulina Zavistanaviciute, Vytaute Starkute, Egle Zokaityte, Vita Lele, Agila Dauksiene, Michael Grashorn, Ludwig E. Hoelzle, Anara Mendybayeva, Raushan Ryshyanova, Romas Gruzauskas

Author(s): Laura Menchetti, Agnese Taticchi, Sonia Esposto, Maurizio Servili, David Ranucci, Raffaella Branciari, Dino Miraglia

Antimicrobial effect of oregano and thyme essential oils (1%) in minced pork was assessed after storage at 3°C/7 days in a vacuum. The inhibition of S. Typhimurium depended mainly on the fat content (logarithmic dependence) and to a lesser degree on the pH, whereas pH was not found to be a significant predictor in the case of L. monocytogenes. The results show that only lean minced meat (up to 5% of fat) is a suitable matrix for pathogen control by essential oils.

Unlike human isolates, environmental Escherichia coli isolates have not been thoroughly investigated for the diversity and transferability of antibiotic-resistant plasmids. In this study, antibiotic-resistant strains from marine sediment (n = 50) and clams (n = 53) were analyzed (i) for their plasmid content using a PCR-based plasmid replicon typing (PBRT) kit and (ii) for the transferability of plasmid-associated antibiotic resistance (AR) traits by mating experiments.

The emergence of bacterial strains resistant to different antibiotics has prompted the search for new sources of antimicrobial compounds. Studies have shown that jambolan [Syzygium cumini (L.) Skeels], a tropical fruit from the Mirtaceae family, contains a great variety of phytochemical compounds with high antioxidant and antimicrobial activity. This study aimed to determine the centesimal composition and physicochemical characteristics of the pulp and seed of S.

The fucosylated carbohydrate moieties on intestinal epithelial cells (IECs) are involved in the creation of an environmental niche for commensal and pathogenic bacteria. Core fucosylation catalyzed by fucosyltransferase 8 (Fut8) is the major fucosylation pattern on the N-glycans of the surface glycoproteins on IECs, however, the role of IECs core fucosylation during infection remains unclear.

A strain named as P. aeruginosa 2016NX1, which could produce phenazine and cereusitin, was isolated from the root of Millettia specisoa. Phenazines were extracted, isolated and purified by chloroform, thin‐layer chromatography, column chromatography and high performance liquid chromatography. Then the purified materials were identified by analysis of nuclear magnetic resonance (NMR). The major yellow component is 1‐hydroxyphenazine and the minor blue component is cereusitin A.

A novel selective enrichment broth (SLB) combined with a loop‐mediated isothermal amplification (LAMP) kit was developed for inspection of Salmonella in ready‐to‐eat fruits and vegetables. A novel selective enrichment broth was developed for the inspection of Salmonella. The recovery of injured Salmonella in SLB was superior to Selenite Cystine Broth. The growth of Salmonella and inhibitory non‐Salmonella in SLB was exceeding among LB and SC.

The occurrence of multidrug-resistant pathogenic bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant Acinetobacter baumannii (MDRAB), extended-spectrum β-lactamase (ESBL) Escherichia coli, and Pseudomonas aeruginosa, has become a serious problem in animals and public.

Significance and Impact of the Study: In this study, the microbiological quality and safety of minimally processed vegetables sold in the city of Piracicaba, SP, Brazil, were evaluated through the detection of Salmonella spp., generic Escherichia coli and other Enterobacteriaceae. The results obtained point to poor microbiological quality and safety of a few samples, as generic E. coli was detected in 16 out of 100 samples and Salmonella was isolated from one of them.

Spectinomycin is a ribosome-binding antibiotic that blocks the translocation step of translation. A prevalent resistance mechanism is modification of the drug by aminoglycoside nucleotidyl transferase (ANT) enzymes of the spectinomycin-specific ANT(9) family or by enzymes of the dual-specificity ANT(3)(9) family, which also acts on streptomycin. We previously reported the structural mechanism of streptomycin modification by the ANT(3)(9) AadA from Salmonella enterica.

Streptomyces is the most frequently described genus of Actinomycetes, a producer of biologically active secondary metabolites. Indeed, the Streptomyces species produces about 70% of antibiotics and 60% of antifungal molecules used in agriculture. Our study was carried out with the goal of isolating and identifying antimicrobial secondary metabolites from Streptomyces misionensisV16R3Y1 isolated from the date palm rhizosphere (southern Tunisia).

Salmonella enterica serovar Typhimurium is an important foodborne pathogen that causes diarrhea. S. Typhimurium elicits inflammatory responses and colonizes the gut lumen by outcompeting the microbiota. Although evidence is accumulating with regard to the underlying mechanism, the infectious stage has not been adequately defined. Peptidoglycan amidases are widely distributed among bacteria and play a prominent role in peptidoglycan maintenance by hydrolyzing peptidoglycans.

Author(s): Weiwei Wang, Jingzhen Liang, Mengya Shi, Guo Chen, Yu Huang, Yan Zhang, Zengzhi Zhao, Min Wang, Min Li, Meilan Mo, Tianchao Wei, Teng Huang, Xiumiao He, Ping Wei

Author(s): Aline Morgan von Hertwig, Beatriz Thie Iamanaka, Dionísio Pedro Amorim Neto, Josiane Bueno de Rezende, Ligia Manoel Martins, Marta Hiromi Taniwaki, Maristela Silva Nascimento

To identify the free‐living amoeba (FLA) and amoeba resistant bacteria (ARB) accumulated in zebra mussels and in the water in which they are found, mussels were collected at two locations in the Ebro river basin (North East Spain). Free‐living amoebas and bacteria were isolated from mussel extracts and from natural water.

ABSTRACT The prophage BTP1 is highly conserved among strains of the pathogenic lineage Salmonella Typhimurium ST313. We aimed to analyze the role of BTP1 and the gene bstA(BTP1-encoded) in virulence of S. Typhimurium D23580, the ST313 lineage 2 reference strain.

In the above article, author Priscila Guerra's name was initially misspelled. This has now been corrected.

Author(s): Yuanyuan Song, Bassam A. Annous, Xuetong Fan

Author(s): Jun-Won Kang, Woo-Ju Kim, Dong-Hyun Kang

In 1996, the Food Safety and Inspection Service published its Pathogen Reduction; Hazard Analysis and Critical Control Point (PR;HACCP) rule. The intention of this program was to reduce microbial contamination on meat, poultry, and egg products. The program was implemented in stages between January 1998 and January 2000, with sampling for Escherichia coli ( E. coli ) O157:H7 and/or Salmonella in large production establishments beginning in 1998.

The U.S. Food and Drug Administration (FDA) conducted a sampling assignment in 2014 to ascertain the prevalence of Cronobacter spp. and Salmonella in the processing environment of facilities manufacturing milk powder.Cronobacter was detected in the environment of 38 (69%) of 55 facilities.

More efficient sampling and detection methods of pathogens on fresh produce are needed. The purpose of this study was to compare a novel rinse/membrane filtration method (RMFM) to a more traditional sponge rubbing or stomaching method in processing jalapeño peppers and cantaloupe samples for detection of Escherichia coli , Salmonella enterica , and Listeria monocytogenes .