Research Publications (Food Safety)

CgtA, a highly conserved 50S ribosome-associated essential GTPase, acts as a repressor of the stringent stress response under nutrient-rich growth conditions to suppress basal levels of the alarmone ppGpp in V. cholerae. To further explore the in vivo functionality of CgtA, we introduced an amino acid substitution, i.e., Gly98Asp, in a conserved glycine residue in the N-terminal domain. The constructed V. cholerae mutant was designated CgtA(G98D).

Mastitis is a significant disease in dairy ruminants, causing economic losses to the livestock industry and severe risks to public health. Antibiotic therapy is one of the most crucial practices to treat mastitis, although the susceptibility of caprine mastitis pathogens to current antibiotics has not been tested under standard or modified incubation conditions.

Microbiology Resource Announcements, Ahead of Print. We report the isolation, identification, and assemblies of three antibiotic-producing soil bacteria (Staphylococcus pasteuri, Peribacillus butanolivorans, and Micrococcus yunnanensis) that inhibit the growth of Neisseria commensals in coculture.

mBio, Ahead of Print. For decades, the remote island nation of Samoa (population ~200,000) has faced endemic typhoid fever despite improvements in water quality, sanitation, and economic development. We recently described the epidemiology of typhoid fever in Samoa from 2008 to 2019 by person, place, and time; however, the local Salmonella enterica serovar Typhi (S. Typhi) population structure, evolutionary origins, and genomic features remained unknown.

Antimicrobial Agents and Chemotherapy, Ahead of Print. Frequent outbreaks of Salmonella Typhimurium infection, in both animal and human populations and with the potential for zoonotic transmission, pose a significant threat to the public health sector. The rapid emergence and spread of more invasive multidrug-resistant clinical isolates of Salmonella further highlight the need for the development of new drugs with effective broad-spectrum bactericidal activities.

Mechanism characterization on cross protection between different stresses is important for microbial intervention optimizations to ensuring food safety. In our previous work, ethanol adaptation was found to induce cross-protection against freezing stress in Salmonella Enteritidis. The current work aimed to uncover the underlying mechanisms of this phenomenon using proteomic and mutagenic techniques.

The objective of the present study was to compare the growth of food-pathogens Listeria monocytogenes, Salmonella enterica, food spoilage Bacillus subtilis, an industrial milk product isolate, and spore-forming Paenibacillus in commercially available ultrahigh temperature processed (UHT) bovine milk and non-dairy, plant-based beverages (coconut, almond, cashew) stored at chilled and ambient temperatures (4 °C, 8 °C or 20 °C).

Salmonella enterica serovar Typhimurium monophasic variants (Salmonella 4,[5],12:i:) has increased dramatically, causing human salmonellosis and colonization in pigs. With a difference to S. Typhimurium, the monophasic variants of S. Typhimurium lose the gene cassettes encoding the second phase flagellin.

The adaptability of foodborne pathogens to sublethal concentrations of antimicrobials including essential oils poses a great threat to food safety. The aim of this study was to evaluate the effect of pre-exposure of Origanum vulgare L. essential oil (OVEO) on the tolerance of Yersinia enterocolitica and explore its adaptive response mechanism by the RNA-Seq.

To date, Cd contamination of cropland and crops is receiving more and more attention around the world. As a plant hormone, abscisic acid (ABA) plays an important role in Cd stress response, but its effect on plant Cd uptake and translocation varies among plant species.

This study aimed to optimize the ultrasonic-assisted extraction of the anti-Vibrio parahaemolyticus substances of Phellodendri Chinensis Cortex (ASPC), identify their active substances, and investigate their application in shrimp storage. The ultrasonic-assisted extraction conditions of ASPC were optimized through a single-factor experiment combined with response surface methodology.

A novel chromosome-encoded aminoglycoside O-nucleotidyltransferase AadA33 was identified in Providencia vermicola strain P13. The AadA33 shares the highest amino acid identity of 51.28% with the function characterized AadA31. Antibiotic susceptibility testing and enzyme kinetics analysis revealed that the function of AadA33 is to mediate spectinomycin and streptomycin resistance.

Gallium (Ga) is considered a high-tech Critical Metal, used in the manufacture of several microelectronic components containing either gallium arsenide (GaAs) or gallium nitride (GaN). The current high demand for this critical metal urges the development of effective recovery processes from secondary resources such as mine tailings or electronic recycling material.

Listeria monocytogenes biofilm is a consistent source of cross-contamination, both in housing storage and food processing environments. This study monitored the dynamic process of L. monocytogenes ST9 and ST87 biofilms, as well as their cross-contamination behaviors at various stages of formation. Scanning Electron Microscopy (SEM) captured the honeycomb-like structures and extracellular polymeric substances (EPS) during the biofilm formation.

Human noroviruses (HuNoVs) have been found as the leading cause of acute gastroenteritis outbreaks in all age groups and are significantly correlated with the consumption of shellfish. In this study, the contamination of HuNoVs in shellfish was estimated through a systematic review and meta-analysis. Studies on the contamination of HuNoVs in shellfish were searched from PubMed, Web of Science, Embase, and Cochrane Library from January 2000 to August 2021.

In this work, a fluorescence and colorimetric dual-mode immunoassay for detecting zearalenone (ZEN) was established. This platform relied on the dephosphorylation of p-nitrophenyl phosphate (PNPP) by alkaline phosphatase (ALP) to produce yellow p-nitrophenol (PNP). And the internal filtration effect between G-quadruplex/N-methylmesoporphyrin IX (G4/NMM) and PNP led to fluorescence quenching of G4/NMM.

Dinoflagellate inhabitants of the reef-building corals exchange nutrients and signals with host cells, which often benefit the growth of both partners. Phytohormones serve as central hubs for signal integration between symbiotic microbes and their hosts, allowing appropriate modulation of plant growth and defense in response to various stresses. However, the presence and function of phytohormones in photosynthetic dinoflagellates and their function in the holobionts remain elusive.

Ocular toxoplasmosis (OT) is retinochoroiditis caused by Toxoplasma gondii infection, which poses a huge threat to vision. However, most traditional oral drugs for this disease have multiple side effects and have difficulty crossing the blood-retinal barrier, so the new alternative strategy is required to be developed urgently. Histone deacetylases (HDAC) inhibitors, initially applied to cancer, have attracted considerable attention as potential anti-Toxoplasma gondii drugs.

In this study, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous determination of deoxynivalenol, aflatoxin B1, zearalenone, ochratoxin A, T-2 toxin and fumonisin B1 in feed and feedstuff was established.

Winter savory (Satureja montana L.) is a well-known spice and medicinal plant with a wide range of activities and applications. Two subspecies of S. montana, subsp. montana and subsp. variegata, were used for the preparation of seven different extracts: steam distillation (essential oil (EO) and hydrolate (HY)), subcritical water (SWE), ultrasound-assisted (UAE-MeOH and UAE-H2O), and microwave-assisted (MAE-MeOH and MAE-H2O) extraction.

Human norovirus is the leading cause of foodborne illness in the United States. Among many of the challenges related to understanding and controlling noroviruses, the influence of host microbiota on viral pathogenesis has continued to remain the subject of increased focus. Foundational work previously suggested that some bacteria may directly interact with noroviruses and promote infection.

Vibrio parahaemolyticus is a foodborne pathogen that is naturally found in estuarine and marine environments. Seafood may acquire this pathogen from its growing environment or through cross-contamination. Recent studies have shown that the occurrence and levels of this pathogen in seafood at harvest are influenced by aquaculture practices and environmental factors, particularly sea surface temperature and salinity conditions.

Greenbelts around roads are an essential part of the ecosystem that can reduce heavy metal contamination from traffic and contribute to sustainable development. However, only limited studies have examined the rapid detection of heavy metal content in urban road greenbelt zones.

Foodborne disease caused by pathogenic bacteria remains a great threat to public health throughout the world. Herein, a colorimetric assay was developed for rapid and selective detection of Salmonella typhimurium (S. typhimurium) based on Fe/4Cu-metal organic framework nanorods (Fe/4Cu-MOF).

BCp12, a novel antimicrobial agent derived from buffalo milk, poses superior antimicrobial activity against Staphylococcus aureus. In the present study, the effect of BCp12 on the cell wall synthesis and molecular pathways of Staphylococcus aureus was studied by the CLSM, SEM and proteomics analyses to facilitate the development of this novel antimicrobial peptide.