Research Publications (Food Safety)

The development of new types of fungicides for agriculture and medicine is highly desirable due to the uprising fungal resistance against commonly used compounds. Herein, 4-substituted-4-nitropyrazolin-5-ones (nitropyrazolones) were proposed as highly active fungicides of the novel structural type.

Hundreds of different fast-growing Salix hybrids have been developed mainly for energy crops. In this paper, we studied water extracts from the bark of 15 willow hybrids and species as potential antimicrobial additives. Treatment of ground bark in water under mild conditions extracted 12–25% of the dry material.

Staphylococcal enterotoxins (SEs) secreted by Staphylococcus aureus frequently contaminate food and cause serious foodborne diseases but are ignored during food processing and even cold-chain storage. Notably, SEs are stable and resistant to harsh sterilization environments, which can induce more serious hazards to public health than the bacterium itself. Therefore, it is necessary to develop promising strategies to control SE contamination in food and improve food safety.

Companilactobacillus crustorum usually serves as a starter culture for the food industry. Recent studies revealed that this species also possesses probiotic properties. Genome engineering, including point mutation or gene deletion, is desired to understand the mechanisms of its probiotic and fermentation properties. To tackle the hurdle in genetic manipulation in C. crustorum, here, we established a fast and easy CRISPR/Cas9-based platform for precise genome editing in this species.

An excellent bactericidal effect of octyl gallate (OG)-mediated photodynamic inactivation (PDI) against foodborne pathogens (Escherichia coli and Staphylococcus aureus) was evaluated in relation to the mode of action. UV-A irradiation (wavelength, 365 nm; irradiance, 8.254 ± 0.18 mW/cm2) of the bacterial suspension containing 0.15 mM OG could lead to a >5-log reduction of viable cell counts within 30 min for E. coli and only 5 min for S. aureus.

In this study, the dihydropteroate synthase of Staphylococcus aureus was obtained, and its recognition mechanisms for 31 sulfonamide drugs were studied. Results showed that their core structure matched well with the binding pocket of para-aminobenzoic acid, and all the sulfonamide side chains were out of the binding pocket. Hydrogen bonds and hydrophobic interactions were the main intermolecular forces, and the key amino acids were Gly171 and Lys203.

Cinnamaldehyde is a natural antimicrobial food preservative. Previous studies have suggested that cinnamaldehyde interacts with the cell membrane, but the molecular targets of cinnamaldehyde action on foodborne pathogens are still unclear. In this study, the structural changes of Staphylococcus aureus and Escherichia coli cells were observed after cinnamaldehyde treatment.

Staphylococcus aureus can cause many diseases and has a strong tendency to develop resistance to multiple antibiotics. In this study, benzyl isothiocyanate (BITC) was shown to have an excellent inhibitory effect on S. aureus ATCC25923 and methicillin-resistant S. aureus strains, with a minimum inhibitory concentration of 10 μg/mL. Under a scanning electron microscope, shrinkage and lysis of the cellular envelope were observed when exposed to BITC, and a bactericidal mode of BITC against S.

Staphylococcus aureus RF122 is a major pathogen that causes bovine mastitis, which is the most prevalent and costly disease in the milk and dairy industry. S. aureus expresses various virulence factors that are especially highly associated with iron metabolism, and the bacterial ferrous iron transport system Feo is important for bacterial growth or virulence in mammalian hosts. In this study, we evaluated a new antimicrobial agent, PHT-427, targeting the S.

The development of new preservatives is an ongoing investigation in the food industry, especially those which are safe and environmentally friendly. In this study, biosurfactant sophorolipids (SLs) functionalized with amino acids were developed as efficient preservative agents. SLs were first isolated from fermentation broth by Candida bombicola ATCC 22214, hydrolyzed, and purified by extraction.

Staphylococcus aureus (S. aureus) is one of the foodborne pathogens that can cause infectious diseases and food poisoning. Herein, colorimetric and fluorescent dual-mode nanoprobes were developed for ultrasensitive detection of S. aureus to immediately respond to public health emergencies, reduce false positives, and improve measurement accuracy and persuasiveness.

Lasso peptides, a class of ribosomally synthesized and post-translationally modified peptides (RiPPs) secreted by bacteria, have antimicrobial activity. Here, a novel lasso peptide, microcin Y (MccY), was discovered and characterized. The gene cluster for MccY synthesis was cloned for expression in Escherichia coli. This peptide was purified by HPLC and characterized by Q-TOF.

Staphylococcal enterotoxins (SEs) are responsible for frequent food poisoning outbreaks worldwide. Specific identification of SEs is crucial for confirmation of food poisoning, tracking of the incriminated foods or food ingredients, and removal from the food chain. Here, we report on a new food testing protocol addressing the challenge of low abundance of SEs in contaminated food and high sequence heterogeneity.

Nowadays, films with antibacterial activity and applied for freshness monitoring by colorimetric response have been drawing growing attention in food packaging. However, the development of versatile antibacterial and colorimetric agents is still highly desirable. Herein, WO3 nanorods are incorporated in a polyvinyl alcohol (PVA) matrix to develop a novel composite film with photothermal antibacterial activity and freshness monitoring faculty.

Rhamnolipid is the main group of biosurfactants predominantly produced by Pseudomonas aeruginosa, a ubiquitous and opportunistic pathogen, which limits its large-scale exploitation. Thus, cost-effective rhamnolipid production from a newly isolated nonpathogenic Enterobacter sp. UJS-RC was investigated. The highest rhamnolipid production (4.4 ± 0.2 g/L) was achieved in a medium constituting agroindustrial wastes (sugarcane molasses and corn steep liquor) as substrates.

This study presents a method for modifying pectin with phenolic acids catalyzed by lipase in a two-phase system of water/tetrahydrofuran. Salicylic acid (SA) and its isomers, including m-hydroxybenzoic acid (MHBA) and p-hydroxybenzoic acid (PHBA), were grafted onto pectin, and the products were characterized via UV–vis, Fourier transform infrared spectroscopy (FTIR), and 1H NMR analyses to explore the reaction process and mechanism between pectin and the three phenolic acids.

A strain isolated from the gut of Pantala flavescens was characterized as Trichoderma harzianum QTYC77. The strain was assessed as a potential biocontrol agent against Fusarium oxysporum f. sp. cucumerinum (FOC). Mycoparasitism and competing abilities of T. harzianum QTYC77 lead to inhibition of the mycelial growth of FOC, with the inhibition rate of 70.99%, in dual culture assays.

In part as a result of the production of an enterotoxin, Staphylococcus aureus is a highly infectious pathogen and is a considerable threat to food hygiene and safety. Clinical mastitis models were established by S. aureus nipple-tube perfusion. The influence of mastitis on the mammary-gland-tissue proteomic profile was investigated using isobaric tags for relative and absolute quantitation.