Research Publications (Food Safety)

In poultry slaughtering, cross-contamination with Salmonella Enteritidis is a constant ongoing challenge. Interaction between food contact surfaces can potentially transfer pathogenic material like feces from carcasses to another one. One approach to break this chain is to modify surfaces that frequently come into contact with the animal during the slaughtering process.

Honey, a nutritious and healthy product, has recently been the focus of research due to its characteristic chemical composition and a wide variety of biological properties.

Colorimetry has emerged as a promising option for pathogenic detection. Herein, a novel method based on saltatory rolling circle amplification (SRCA) combined with photosensitization colorimetric assay (SRCA-C) was developed for rapid and sensitive detection of Salmonella in food. The target identification and signal amplification are realized by SRCA to produce a large amount of double-stranded DNA.

Traditional thermal processing often denatures protein, causing loss of active ingredients and nutrients in dairy products, even the formation of 5-hydroxymethylfurfural (5-HMF) and advanced glycation end products (AGEs). In this study, the high hydrostatic pressure (HHP) combined with moderate heat (50 °C) pre-incubation (MHHP) was utilized to explore the alternative processing to reduce the levels of 5-HMF and AGEs in milk.

Honey is an important bee product with its nutritional and medicinal properties. Characterization of different monofloral honey has importance for focusing on honey’s biocomponents and the potential use of its medicinal applications. Although Black cumin (Nigella sativa L.) is a valuable monofloral honey, there are less study about its both chemical and biochemical study in literature.

Bee pollen (BP) and bee bread (BB) have attracted great attention due to their biological activities including antibacterial activity. However, the mechanism of antibacterial activity is largely unknown.

The aim of this study was to establish a rapid and visual nucleic acid isothermal amplification method for the detection of viable Staphylococcus aureus (S. aureus) in pork and pork products. The method was based on saltatory rolling circle amplification (SRCA) combined with propidium monoazide (PMA). Eighteen S. aureus strains and 29 non-S. aureus strains were used for the specificity evaluation.

The effects of sumac, cumin, black pepper and red pepper diethyl ether extracts on the growth of eight foodborne pathogens (FBP) and their biogenic amine (BA) production were investigated in histidine decarboxylase broth. The antimicrobial effect was determined by the minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations. Sumac extract showed the highest antimicrobial activity against FBP.

Recently, frequent outbreaks of foodborne diseases have attracted increasing attention, and how to rapidly detect foodborne pathogens has also become an urgent issue. Herein, we reported the colorimetric sensor based on chitosan-coated magnetic nanoparticles (CS@MNPs) for rapidly broad-spectrum detection of the total bacterial count, whose color change can be visible to the naked eye without any other sophisticated instruments.

This study aimed to develop a combination of immunomagnetic separation (IMS) and real-time PCR (qPCR) techniques to detect and analyze Salmonella spp. (SAL), Listeria monocytogenes (LM), and Escherichia coli O157:H7 (O157: H7) in meat samples quickly and accurately. Bacteria-specific immunomagnetic beads (IMBs) were prepared from carboxyl magnetic beads and affinity-purified polyclonal antibodies using a novel magnetic bead activator.

Industrial production of Tenebrio molitor larvae (TML), a promising source of protein for food, requires safety, fast growth, maturation, and high survival. Probiotics, enhance host growth and protect against pathogens and diseases. This study evaluates the effects of three probiotic bacteria immobilized on the diet of mealworms, on growth performance, nutritional value, and microbial load of T. molitor larvae.

The scope of this work was to study the efficacy of the combination of sonication at 35 or 130 kHz with three temperature treatments: 20, 50 and 55 ºC, on the population of artificially inoculated Listeria innocua in strawberries, and on their overall quality. Prior in vitro results showed that temperature was the main factor in decreasing L.

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The potential employment of 18 commercial Tunisian essential oils (EOs) as natural food preservatives was investigated. Their antimicrobial activity was evaluated against two food-borne bacteria (Escherichia coli O157:H7 and Klebsiella pneumoniae) by the agar-well diffusion method and, subsequently, by determining the minimum inhibitory concentration (MIC); while their antioxidant activity was assayed by the DPPH test.

Listeria in food, are a serious risk to consumer’s health that may even have a fatal outcome. To analyze Listeria in food, the methods used must provide reliable results and detect all strains of Listeria. Several qPCR systems have been published for the identification of Listeria monocytogenes, innocua, ivanovii, welshimeri and seeligeri. PCR systems for Listeria spp. have also been published. However, they do not detect all known Listeria.

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.

With its ability to easily infect each step of food production chain, Salmonella spp. stands as one of the most important foodborne pathogens which impose threats against economy and human health by creating high morbidity and mortality, worldwide.

The effect of low-temperature plasma generated at atmospheric pressure was studied in term of reduction of bacterial contamination and influence on nutritional characteristics of allspice (Pimenta dioica). The low-temperature plasma was generated in ambient air using Diffuse Coplanar Surface Barrier Discharge (DCSBD). The bacterial species inoculated on the surface of samples were reduced in dependence on exposure time.

Pomegranate peel extract (PGE) is a new promising natural alternative control substance with large spectrum of activity against wide range of pathogenic microorganisms. In the present study, PGE was firstly investigated as natural antimicrobial against Listeria monocytogenes both in vitro and on fresh-cut fruits. The in vitro results showed quick and strong bactericidal and bacteriostatic activity against five different strains which were almost completely inhibited by the extract.

The aim of the study was to assess the antibacterial properties of bioactive compounds released during the fermentation of goat’s milk by selected bacterial strains that are part of the kefir grain microflora. The material used in the experiments was kefir grain microflora (Lactobacillus kefiranofaciens subsp.

Activity-guided fractionation based on in vitro assays was used to identify antibacterial components in the residue wasted in the manufacturing process of aged garlic extract (AGE). Antimicrobial activity of the hexane extract of aged garlic-derived residue (AGR) was evaluated against clinically isolated Gram-positive and -negative bacteria including levofloxacin (LVX)-resistant strains.

We examined the initial attachment of E. coli to abiotic surfaces conditioned with cereal extracts. The extracts were water-soluble fractions prepared from flours of barley, quinoa, rice, and wheat. Strains used were E. coli ATCC 8739, E. coli NBRC 3301, E. coli NBRC 3302, E. coli NBRC 13168, E. coli NBRC 13891, and E. coli O157:H7 sakai.

Salmonella is a major cause of foodborne illness throughout the world and has resulted in a serious of public health issues over the past decades. The conventional culture methods for Salmonella detection are laborious and time-consuming; thus a variety of new methods have been developed to enable rapid detection.

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