Research Publications (Food Safety)

Zhao, Dongjun et al. Thermal pasteurization can achieve the U.S. Food and Drug Administration–required 5-log reduction of pathogenic Escherichia coli O157:H7 and Cryptosporidium parvum in apple juice and cider, but it can also negatively affect the nutritional and organoleptic properties of the treated products.

Yeater, Michael C. et al.

Casco, G. et al.

Al-Qadiri, Hamzah et al. This study investigated the growth and survival of three foodborne pathogens (Clostridium perfringens, Campylobacter jejuni, and Listeria monocytogenes) in beef (7% fat) and nutrient broth under different oxygen levels. Samples were tested under anoxic (<0.5%), microoxic (6 to 8%), and oxic (20%) conditions during storage at 7°C for 14 days and at 22°C for 5 days. Two initial inoculum concentrations were used (1 and 2 log CFU per g of beef or per ml of broth).

Jensen, Dane A. et al. Hand washing is recognized as a crucial step in preventing foodborne disease transmission by mitigating cross-contamination among hands, surfaces, and foods. This research was undertaken to establish the importance of several keys factors (soap, soil, time, and drying method) in reducing microorganisms during hand washing.

Livezey, Kristin W. et al. Escherichia coli O157:H7 and six serovars (O26, O103, O121, O111, O145, and O45) are frequently implicated in severe clinical illness worldwide. Standard testing methods using stx, eae, and O serogroup–specific gene sequences for detecting the top six non-O157 STEC bear the disadvantage that these genes may reside, independently, in different nonpathogenic organisms, leading to false-positive results.

Eady, Matthew et al. This study was designed to evaluate hyperspectral microscope images for early and rapid detection of Salmonella serotypes Enteritidis, Heidelberg, Infantis, Kentucky, and Typhimurium at incubation times of 6, 8, 10, 12, and 24 h. Images were collected by an acousto-optical tunable filter hyperspectral microscope imaging system with a metal halide light source measuring 89 contiguous wavelengths every 4 nm between 450 and 800 nm.

Keller, Susanne E. et al. The survival of Salmonella on dried chamomile flowers, peppermint leaves, and green tea leaves stored under different conditions was examined. Survival and growth of Salmonella was also assessed after subsequent brewing using dried inoculated teas. A Salmonella enterica serovar cocktail was inoculated onto different dried tea leaves or flowers to give starting populations of approximately 10 log CFU/g.

Delbeke, Stefanie et al. The survival of Salmonella and Escherichia coli O157:H7 on strawberries, basil leaves, and other leafy greens (spinach leaves, lamb and butterhead lettuce leaves, baby leaves, and fresh-cut iceberg lettuce) was assessed at cold (<7°C) and ambient temperatures. All commodities were spot inoculated with E. coli O157:H7 or Salmonella to obtain an initial inoculum of 5 to 6 log and 4 to 5 log CFU/g for strawberries and leafy greens, respectively.

du Plessis, Erika M. et al. The potential transfer of human pathogenic bacteria present in irrigation water onto fresh produce was investigated, because surface water sources used for irrigation purposes in South Africa have increasingly been reported to be contaminated with enteric bacterial pathogens.

Williams, K. J. et al. A longitudinal study was conducted to assess the methods available for detection of Escherichia coli O157 and to investigate the prevalence and occurrence of long-term shedding and super shedding in a cohort of Australian dairy heifers. Samples were obtained at approximately weekly intervals from heifers at pasture under normal management systems.

Publication date: October 2015
, Volume 56
Author(s): María Ruiz-Rico , Cristina Fuentes , Édgar Pérez-Esteve , Ana I. Jiménez-Belenguer , Amparo Quiles , María D. Marcos , Ramón Martínez-Máñez , José M. Barat

Publication date: October 2015
, Volume 56
Author(s): Ramin Khaksar , Traci Carlson , Donald W. Schaffner , Mahni Ghorashi , Dieter Best , Srikanth Jandhyala , Julie Traverso , Sasan Amini

Publication date: October 2015
, Volume 56
Author(s): Igor Tomašević , Jelena Petrović , Milica Jovetić , Smiljana Raičević , Milica Milojević , Jelena Miočinović

To the Editor: Shigella sonnei causes a bacillary dysentery called shigellosis. Shiga toxins 1 (Stx1) and 2 (Stx2) are mainly produced by Shiga toxin–producing Escherichia coli (STEC), but Stx1 can also be produced by S. dysenteriae serotype 1 (1).

To the Editor: Shigellosis is an uncommon infection in many industrialized countries, and many cases are linked to travel to Shigella spp.–endemic countries. The epidemiology of Shigella infections in developing countries is changing. S. sonnei seems to be replacing the more antigenically diverse S. flexneri in regions undergoing economic development and improvements in water quality (1).

We analyzed 1,093 Vibrio cholerae isolates from the Democratic Republic of the Congo during 1997–2012 and found increasing antimicrobial drug resistance over time. Our study also demonstrated that the 2011–2012 epidemic was caused by an El Tor variant clonal complex with a single antimicrobial drug susceptibility profile.

Publication date: 2 July 2015
, Volume 204
Author(s): Yun Jiang , Shuang Yin , Edward G. Dudley , Catherine N. Cutter

Fernando Gómez, Dajun Qiu, Rubens M. Lopes, Senjie Lin

The microaerophilic food-borne pathogen Campylobacter jejuni uses complex cytochrome-rich respiratory chains for growth and host colonization. Cytochrome c biogenesis requires haem ligation to reduced apocytochrome cysteines, catalysed by the cytochrome c synthase, CcsBA. While ccsBA could not be deleted, we showed that the thiol reductase DsbD and the CcsX homologue Cj1207 are involved in, but not essential for, cytochromes c biogenesis.

Clostridium perfringens enterotoxin (CPE) is a three-domain polypeptide, which binds to Claudin-3 and Claudin-4 with high affinity. Because these receptors are highly differentially expressed in many human tumors, claudin-3 and claudin-4 may provide an efficient molecular tool to specifically identify and target biologically aggressive human cancer cells for CPE-specific binding and cytolysis.

Publication date: Available online 31 March 2015
Food and Chemical Toxicology
Author(s): Andrew D. Monnot , Whitney V. Christian , Matthew M. Abramson , Mark H. Follansbee

Publication date: May 2015
, Volume 71
Author(s): Karla Aguilar , Alfonso Garvin , Ebner Azuara , Albert Ibarz

Tuberculosis (TB) is a devastating disease that affects humans and many animal species. In humans, TB is mainly caused by Mycobacterium tuberculosis, whereas most cases in cattle are caused by Mycobacterium bovis. However, M. bovis can also cause, albeit rarely, human TB. In PNAS, Wu et al. (1) report the...

Conventional methods for the detection of Salmonella based on culturing are time-consuming and laborious. The aim of this study was to develop a template preparation method and polymerase chain reaction (PCR) assay for the detection of Salmonella spp. in egg yolk, pizza, ground beef, pork, pork sausage, chicken drumsticks, mayonnaise and Minas cheese. The DNA extraction was performed with thermal lysis followed by nucleic acid purification with phenol-chloroform.