Research Publications (Food Safety)

Salmonella enterica remains a leading cause of food-borne diseases worldwide. Serotype information is important in food safety and public health activities to reduce the burden of salmonellosis. In the current st...

Yersinia pestis is a highly virulent pathogen and the causative agent of bubonic, septicemic, and pneumonic plague. Primary pneumonic plague caused by inhalation of respiratory droplets contaminated with Y. pestis is nearly 100% lethal within 4 to 7 days without antibiotic intervention. Pneumonic plague progresses in two phases, beginning with extensive bacterial replication in the lung with minimal host responsiveness, followed by the abrupt onset of a lethal proinflammatory response.

The stringent response is an essential mechanism of metabolic reprogramming during environmental stress that is mediated by the nucleotide alarmones guanosine tetraphosphate and pentaphosphate [(p)ppGpp]. In addition to physiological adaptations, (p)ppGpp also regulates virulence programs in pathogenic bacteria, including Salmonella enterica serovar Typhimurium. S.

Wine and alcoholic apple cider are commonly back-sweetened with unpasteurized juice to produce fresh, natural, and palatable sweetened alcoholic beverages. Foodborne pathogens may be introduced from unpasteurized juice into alcoholic beverages through this back-sweetening process. Although pathogens generally do not survive under low pH conditions or high alcohol environment, the die-off of these pathogens has not been established to ensure the safety of the products.

Flies are a vector for spreading foodborne pathogens pertinent to fresh produce, such as Shiga-toxigenic Escherichia coli and Salmonella; however, most studies focus on concentrated animal feeding operations, which do not reflect low-density animal farming practices that often adjoin fruit and vegetable acreage.  In this study, we determined the prevalence of Salmonella in flies collected biweekly on an integrated animal and produce operation over two growin

Pyridoxal 5'-phosphate (PLP) is the biologically active form of vitamin B6, essential for cellular function in all domains of life. In many organisms, such as Salmonella enterica serovar Typhimurium and Escherichia coli, this cofactor can be synthesized de novo or salvaged from B6 vitamers in the environment. Unexpectedly, S. enterica strains blocked in PLP biosynthesis were able to use exogenous PLP and pyridoxine 5'-phosphate (PNP) as the source of this required cofactor, while E.

Salmonella spp. are resilient bacterial pathogens in low-moisture foods. There has been a general lack of understanding of critical factors contributing to the enhanced thermal tolerance of Salmonella spp. in dry environments. In this study, we hypothesized that the moisture content (XW) of bacterial cells is a critical intrinsic factor influencing the resistance of Salmonella spp. to thermal inactivation. We selected Salmonella enterica serotype Enteritidis PT 30 to test this hypothesis.

Despite recent advances in Salmonella-sprout research, little is known about the relationship between Salmonella and the sprout microbiome during sprouting. Sprout spent irrigation water (SSIW) provides an informative representation of the total microbiome of this primarily aquaponic crop.

Author(s): H. Zeng, K. De Reu, S. Gabriël, W. Mattheus, L. De Zutter, G. Rasschaert

Salmonella contamination sources and transmission routes were studied in five Belgian poultry slaughterhouses. Samples from the slaughter and cutting line after cleaning and disinfection were collected, as well as neck skin samples and thighs during slaughter of the first flock.

Foodborne illness caused by consumption of food contaminated with Salmonella is one of the most common causes of diarrheal disease and affects millions of people worldwide. The rising emergence and spread of antimicrobial resistance, especially in some serotypes of Salmonella, has raised a great awareness of public health issues worldwide. To ensure safety of the food processing chain, the development of new food preservatives must be expedited.

ABSTRACT

Author(s): Andrea R. McWhorter, Samiullah Khan, Margaret Sexton, Talia S. Moyle, Kapil K. Chousalkar

Deoxynivalenol (DON) is a widely distributed mycotoxin that frequently occurs in various foodstuffs, and poses a health risk to human and animals. Biodegradation of DON to less- or non-toxic substances using naturally existing microorganisms is considered the best approach for DON detoxification. Although various microorganisms capable of detoxifying DON have been reported; however, such studies on probiotic strains are scarce.

The objective of this survey was to estimate the prevalence, contamination level, and genetic diversity of Salmonella in selected raw, shelled tree nuts (Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios, and walnuts) at retail markets in the United States. A total of 3,374 samples of eight tree nuts were collected from different types of retail stores and markets nationwide between September 2015 and March 2017.

Author(s): Zhengquan Chen, Jie Bai, Xibin Zhang, Shaojun Wang, Kaifeng Chen, Qijie Lin, Chenggang Xu, Xiaoyun Qu, Hongxia Zhang, Ming Liao, Jianmin Zhang

Salmonella  has been linked to many food-borne illnesses and epidemics in both humans and animals. This cross-sectional study determined the prevalence, serovars and factors associated with Salmonella contamination of chickens slaughtered in outlets of the informal markets in Gauteng Province, South Africa. A total of 151 chicken carcasses were randomly collected from 47 outlets.

Salad vegetables purchased from farmers’ markets and grocery stores in central Ohio during the summers of 2015 and 2016 were tested for the presence of Enterobacteriaceae resistant to extended spectrum cephalosporins and carbapenems, Salmonella contamination, and coliform bacteria count. A total of 364 samples were collected from 36 farmers’ markets and 33 grocery stores.

Disk diffusion method to determine antimicrobial activity of plant essential oils was used. While the essential oil extracted from oregano has a high effect on 9 of our test microorganisms (75%), one of them had a medium effect and two of them had a weak effect in the test results.

The lesser-known traditionally processed meat products such as beef kargyong, pork kargyong, satchu, and khyopeh are popular food items in the Himalayan state of Sikkim in India. The present study aimed to assess the microbiological safety of traditional meat products by identifying the potential spoilage or pathogenic bacteria, detecting the enterotoxins, and screening the antibiotic susceptibility patterns.

Author(s): Jing Zhuang, Xiaoyue Ji, Yue Zhu, Wei Liu, Jing Sun, Xinan Jiao, Xiulong Xu

BACKGROUND Fermentation, a traditional food preserving technique and an effective process, widely used to enrich the nutrients diversity and bioactivity of the fermented foods since ancient times. This study aimed at investigating the effects of various fermentation starters on the physicochemical, antioxidant, antimicrobial, and antidiabetic properties of the blueberry juices.

Author(s): Renata Galetti, Rafael Antonio Casarin Penha Filho, Joseane Cristina Ferreira, Alessandro M. Varani, Pavelas Sazinas, Lars Jelsbak, Ana Lúcia Costa Darini

ABSTRACT Biofilm is a predominant lifestyle of bacteria that comprises of cells as collectives enmeshed in a polymeric matrix. Biofilm formation is vital for bacterial species as it provides access to nutrients and protects the cells from environmental stresses. Here we show that interference in biofilm matrix production is a strategy by the competing bacterial species to reduce the ability of the other species to colonize a surface.

The açai palm (Euterpe oleracea) is native to the Amazon basin, a humid tropical forest. High levels of total mesophilic bacteria with high diversity have been consistently reported in açai fruits. As local consumers have few digestive problems, the results of the present study reveal the lactic acid bacteria (LAB) recovered from açai fruits with characteristics that suggest they are possible candidates for probiotics and antagonistic potential against pathogens for the first time.

Author(s): Zhang Jian, Wei Luo, Guifeng Liu, Yang Wang, Shizhong Geng, Zhiming Pan, Xin’an Jiao