Research Publications (Food Safety)

The illicit burn practices on farms promote food contamination that is harmful and must be controlled by improved analytical methods. Polycyclic aromatic hydrocarbons (PAHs), which have high toxic and carcinogenic potential, can contaminate foods, mainly through fire exposure. Considering the toxicity of PAHs, development of sensitive, simple, and solvent-free methods to analyze PAHs in foods is necessary.

In the present work, a new and efficient sample treatment method based on the combination of stirring-dependent magnetic dispersive solid phase microextraction and ferrofluid-based dispersive liquid–liquid microextraction has been developed for the extraction of some pyrethroid pesticides (bifenthrin, phenothrin, tetramethrin, cyhalothrin, permethrin, and cypermethrin) from fruit juices prior to their determination with gas chromatography–mass spectrometry.

A simple methodology for the simultaneous determination of 67 pesticides, 25 veterinary drugs, and aflatoxin M1 in raw milk was developed and validated. After evaluating different combinations of sample preparation protocols, an extraction with acetonitrile:water (2:1) with QuEChERS citrate buffer salts and a combination of RP-C18 and anhydrous magnesium sulfate for the dispersive clean-up, using gas and liquid chromatography couples to mass spectrometry for determination, was selected.

Hemp is one of the most complete plants for industrial and consumer purposes. In the food industry, the main hemp product is the seed oil, which contains a wide spectrum of compounds such as amino acids and fatty acids that are essential for human health. Given its growing consumption, systematic studies were undertaken for the quantification of toxic elements (As, Cd, and Pb) in hemp products, such as seeds (shelled and peeled), oil, protein, and butter.

Minerals such as calcium, magnesium, and potassium which are available in the Ajwa dates are known to play vital roles in the regulation of blood pressure due to their interaction with the arterial resistance. The purpose of this study was to investigate the level of various ions in these date seeds and their correlation to the cardiovascular parameters. The powder was subjected to the electron microscope scanning to investigate the texture.

Vegetables are potential vehicles for the transmission of parasites. Helminth eggs have been detected in produce in various countries around the world, with high prevalence rates. However, there is no standard validated method or ISO to the isolation, concentration, and identification of helminth eggs in salad vegetables, which makes comparison difficult since each study utilized different analytical methods and food matrix.

In this study, a real-time loop-mediated isothermal amplification (Rti-LAMP) combined with immunomagnetic beads separation (IMS) and ethidium bromide monoazide (EMA) treatment was developed for the rapid and ultrasensitive detection of viable Escherichia coli (E. coli) O157:H7 in milk without enrichment. Polyclonal antibodies against E. coli O157:H7 flagellum and specific immunomagnetic beads (IMBs) were prepared.

To detect enrofloxacin (ENR) and ciprofloxacin (CIP) residues in fishery foods, a computer simulation was used to predict and analyze the binding sites existing aptamer specific to ENR and CIP. A new aptamer (SEQ.3) that can recognize ENR and CIP was screened and evaluated, and the dissociation constants (Kd) of SEQ.3 from ENR and CIP were determined to be 210.955 nM and 887.49 nM which are higher than other aptamers SEQ.4 and SEQ.5 by microscale thermophoresis (MST).

Tiamulin is a semi-synthetic derivative of the natural antibiotic pleuromutilin and is widely used as a veterinary drug for swine. Herein, we report the development of a sensitive and reliable method for determining 8α-hydroxymutilin as a marker residue for tiamulin in swine tissue using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Pollution of foods with chloropropanol fatty acid esters is a growing international food safety issue, especially contamination with 3-monochloropropane-1, 2-diol (3-MCPD) esters. Traditional GC/MS method using phenylboronic acid (PBA) as a derivatization reagent has been proven to be high selective.

In recent years, there was increasing concerns on food safety issues associated with fluorescent whitening agents from package materials. Here, we reported the development of a facile and reliable method suitable for high-throughput quantification and identification of two common fluorescent whitening agents (FWA 184 and FWA 367) in cereal products (wheat and rice flour), platformed by high-performance thin-layer chromatography.

The combination of ultra-high-performance liquid chromatography (UHPLC) with time-of-flight mass spectrometry (ToF-MS) is one of the most powerful analytical tools in terms of selectivity, sensitivity and speed.

Polyaniline-modified magnetic halloysite nanotube composites (MHNTs@PANI) were evaluated for the first time as an efficient adsorbent for the magnetic micro-solid-phase extraction of polycyclic aromatic hydrocarbons (PAHs) from beer samples prior to gas chromatography-mass spectrometric detection. MHNTs@PANI were prepared from naturally available material halloysite by coating magnetic HNTs with polyaniline.

Tortoise shell is not only an armor, but also an important structure for storing nutrients for tortoise. The shell from one tortoise strain, Chinemys reevesii (CR), has long been used as a traditional Chinese medicine (TCM). Nowadays, massive CR shells are also processed into healthy food in Asian countries. Despite large-scale culture of CR in nowadays, there still exist massive counterfeit CR shells derived from other strains of tortoises in the market of TCM.

Macrolides are antimicrobials widely used in dairy farming, classified as critically important for human and animal health, and a priority for actions against antimicrobial resistance. Infant formula is used as a substitute for breast milk and should be safe to support child growth and development. In this context, the aim of this study was to validate an analytical method for macrolide analysis in infant formulas produced from bovine milk.

Vibrio cholerae is an important food-borne pathogenic bacterium that causes human disease, resulting in economic losses worldwide. Rapid diagnosis of cholera infection is important to avoid potential spread of disease. In this study, recombinase-aided amplification (RAA) primers labeled with biotin and fluorescein isothiocyanate (FITC) at 5′ end were prepared for the ctxA pathogenic gene of V. cholerae.

A magnetic dispersive solid-phase microextraction procedure (MDμ-SPE) was developed to extract organophosphorus pesticides (OPP), including ethion, chlorpyrifos, diazinon, malathion, and fenitrothion, from vegetable samples before their analysis with gas chromatography/mass spectroscopy (GC/MS). Magnetic graphene@Fe3O4@SiO2@TiO2 nanocomposites were synthesized as a unique sorbent using the sol-gel and co-precipitation procedures.

Bovine β-casein is a highly polymorphic protein, with A1 and A2 representing the most frequent variants identified in Western cattle breeds. Depending on the presence of histidine or proline at position 67 of the sequence, β-casein variants can be grouped in two families: those within the A1 family (A1-like), possessing histidine, and those within the A2 family (A2-like), with proline.

In this paper, using molybdenum disulfide doped with gold nanoclusters (Au NCs@MoS2) as the substrate, an aflatoxin aptamer sensor was constructed utilizing iron porphyrin organic porous material modified with streptavidin and loaded with gold nano-bipyramids (SA-Au NBPs@ porous aromatic framework (PAF)-40-Fe) as a label. The catalyzed reduction current of hydrogen peroxide (H2O2) by Au NBPs@PAF-40-Fe was detected which is proportional to the concentration of aflatoxin B1.

The microbiological contamination of food causes concern for public health due to the pathogenic action of microorganisms and the increasing of antimicrobial resistance observed in bacterial strains.

Salting-out assisted liquid-liquid extraction (SALLE) coupled to dispersive liquid-liquid microextraction (DLLME) was developed as an efficient extraction method for purification and preconcentration of bisphenol A and six analogs (B, E, F, S, BADGE, BFDGE) in canned coffee drinks. Ultra-performance liquid chromatography-tandem mass spectrometry was applied for the determination of the analytes.

This work proposes, for the first time, a method based on homogenous liquid-liquid microextraction with switchable hydrophilicity solvent as extraction phase (SHS-HLLME) for the determination of food-packaging contaminants including dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), di-n-octyl phthalate (DNOP), 4-octylphenol (4-OP), 4-nonylphenol (4-NP), and benzophenone (BZP) in coconut water samples by gas chromatography-mass s

Fruits contain nutrients, minerals, trace elements, vitamins, and phytochemicals that are important in terms of human health. When fruits are consumed in a balanced diet, they have a positive effect with regard to reducing disease risk. As a result of heavy metal contamination of the environment, they can be a potential source of toxic elements so it is important to determine the toxic, essential, and trace elements in fresh fruit and commercial fruit products such as fruit juice, marmalade.

This paper describes a novel strategy based on fluorescence energy transfer (FRET) with green synthesis of carbon quantum dots (CQDs) and gold nanoparticles (GNPs) for the detection of one of the most pathogenic bacteria, Staphylococcus aureus (S. aureus). Novel green CQDs with blue color emission and high quantum yield were synthesized from olive leaves via the hydrothermal method. The fluorescence of the CQDs was quenched in the presence of aptamers and GNPs.

Melamine adulteration is a fraudulent practice to increase the protein content of food in some areas of the world. In 2008, many babies in China suffered from serious illness and death because of melamine-tainted powdered infant formula. The issue prompted researchers to develop methods on detecting melamine in milk powder. Optical spectroscopy technologies have been proven to be effective in identifying and quantifying food contaminants.