Research Publications (Food Safety)

In this work an HPLC/hydrophilic interaction liquid chromatography (HILIC) system for intact glucosinolates was optimized using a weak anion exchange resin to remove carboxylic phenolics that absorbed at the same wavelength (229 nm) as glucosinolates, by selectively protonating contaminating phenolics with pKas from 2.98 to 4 while leaving the second OH of the sulfate of the thioglycosidic linkage (pKa = 1.92) ionized.

Animal feed is a potential route for contaminants like mycotoxins to enter into the human food chain. Hence, close monitoring is fundamental and should be performed with adequate analytical methods. In this study, a commercial ELISA kit for aflatoxin B1 detection in feed corn samples, RIDASCREEN® Aflatoxin B1 30/15, was assessed by the evaluation of some performance parameters.

Photothermal effect of nanomaterial has been applied to the establishment of rapid detection method such as test strip. Previously, the detector for the photothermal test strip method mainly was a bulky thermal imaging camera or an infrared-sensing temperature sensor of which the detection data obtained is unstable due to its susceptibility to environmental changes. Herein, a resistive temperature sensor which is more stable and less susceptible to external environment was adopted.

A selective and reliable method was developed and validated for the determination of 14 lipophilic pesticides in raw propolis by gas chromatography–tandem mass spectrometry (GC-MS/MS) analysis. A test portion of milled sample was extracted with n-hexane followed by back extraction with acetonitrile and cleanup using EMR-Lipid and Florisil column adsorption. Matrix-matched standards were used to compensate for matrix effects.

Due to high toxicity to mammals and hazard to the ecosystem, parathion has been banned or limited for use in many countries. It is essential to ensure food safety by parathion suspecting. On-site testing, as a critical component of the food chain safe system, plays a major role in the protection of food safety and human health.

In this study, a specific monoclonal antibody (mAb) against Alternaria mycotoxin tenuazonic acid (TeA) was prepared and a sensitive indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) for the detection of TeA was developed. Tenuazonic acid coupled with carboxymethoxylamine hemihydrochloride (TeA-CMO) was conjugated to keyhole limpet hemocyanin (KLH) as an immunogen for Balb/c mice injection.

A new method for the quantification of four aflatoxins (AFB1, AFB2, AFG1, and AFG2) in baby food samples is described herein. In this method, the extraction/cleanup step was performed by using multi-walled carbon nanotubes as a sorbent material in a dispersive solid phase procedure. In sequence, these mycotoxins were quantified via liquid chromatographic coupled with tandem mass spectrometry. The method was fully validated according to the EC/657/2002 and SANCO/12571/2013 directives.

Pesticide residues are detected in food items globally at levels that may cause health problems. Paper-based analytical devices have emerged as an alternative low-cost and field-based tools for determining target analytes including the pesticide residues. However, the paper devices with colorimetric detection system are limited by lower sensitivity due to their inability to record wavelength specific signal from the assays when image analysis detection method is used.

We developed a self-priming compartmentalization (SPC) micro-device made of polymethyl methacrylate (PMMA) and integrated a loop-mediated isothermal amplification (LAMP) system for performing multiplex visual detection.

In order to monitor and respond rapidly to outbreaks of food-borne pathogens, establishing rapid and sensitive detection methods is becoming increasingly urgent. In this work, through the synthesis of copper-based metal-organic framework nanoparticles (Cu-MOF NPs) and functionalized with aptamers, we developed a colorimetric protocol to detect Escherichia coli. In a typical experimental procedure, aptamer 1 was immobilized onto microplate to act as capture probes.

In this work, we present a magnetic bead–based immunosensorss for the determination of Escherichia coli O26 in milk. The assay uses commercial Dynabeads® for the capture of the target bacteria from 6-h enrichment broth and horseradish peroxidase–labelled polyclonal antibodies and detection of the peroxidase activity by chronoamperometry. Bovine seroalbumin was used as blocking reagent for reducing the binding of non-specific antibodies to the beads and/or other bacteria.

Loop-mediated isothermal amplification (LAMP) had been employed as a powerful tool to facilitate genetic tests for various food pathogens, as it is easy to perform. Recently, various methods of detecting the LAMP amplicon were developed. In this study, we improved two LAMP assays by combining LAMP with chromatographic flow dipstick (LFD) assays for Salmonella (targeting phoP and invA, respectively).

This preliminary study describes the use of high resolution and accuracy mass spectrometry techniques combined with new generation chemical software products for detecting and identifying contaminants in food commodities. As a first step, the extracts of routine target analysis samples (obtained in our official laboratory responsible for food residues control) were acquired and processed with this method in order to search unknown and non-targeted contaminants in food.

In this paper, the technique of continuous sample drop flow microextraction (CSDF-ME) is developed by the addition of a narrow-necked conical vessel. In the developed technique, an organic solvent denser than water is used for the extraction of organophosphorus pesticides (OPPs) from fruit juice and river water, followed by analysis with GC-MS.

Avermectin (AVM) has been widely used in agriculture and animal husbandry for the treatment of broad spectrum parasitic diseases, but it has a harmful effect on human body through food chain. In this paper, on the basis of anti-AVM specific antibody, expanded mesoporous silica-encapsulated gold nanoparticles (EMSN-AuNPs)-based enzyme-linked immunosorbent assay (ELISA) for the detection of AVM was developed.

Quinolone is a family of widely prescript antibiotics in veterinary medicine. Their excessive use can be causative of quinolone residues in foodstuffs of animal origin. Therefore, a magneto immunofluorescence assay in microwell plate has been developed and validated to screen quinolone in bovine milk. The assay is based on an indirect competitive method where the quinolone in the milk sample competed with the quinolone immobilized on magnetic beads for the anti-quinolone antibody.

Twenty-two mycotoxins were investigated in bread and biscuits samples (n = 115) purchased from Tunisia. Deoxynivalenol (DON), enniatin B (ENB), ENB1, and zearalenone (ZEA) occurred in the samples with ENB detected in all the samples. Whole bread was the most contaminated matrix showing the highest amounts of DON (25.2 ng/g), ENB (10.7 ng/g), and ENB1 (5.4 ng/g). However, biscuits showed a maximum level of ZEA (1.08 ng/g).

The non-destructive method for detection of fungal contamination in peach fruit using hyperspectral imaging was evaluated. Growth characteristics of three major spoilage fungi in peach fruit during decay were estimated. Three quantitative prediction models were then constructed to forecast the microbial content from the HSI datasets. The prediction of fungal contamination on the fruit was visualized with different colors.

In the present study, an elevated temperature homogeneous liquid extraction coupled with ionic liquid‑based dispersive liquid–liquid microextraction was developed to extract five carbamate pesticides (pirimicarb, carbaryl, methiocarb, aldicarb, and carbofuran) from packed fruit juice samples. The method consisted of a two-step procedure in which cyclohexylamine was used in order to extract the target analytes.

Reliable and sensitive detection of Staphylococcal enterotoxin B (SEB) is important to prevent potential human health risk from foods contaminated by SEB. Here, a triple-channel assay was developed for ultrasensitive detection of SEB.

Due to the legislative shortcomings, Atlantic salmon often shares the common name of San Wen Yu (Chinese ideogram 三文鱼) with other salmonids in China, therefore concealing the differences with the rest salmonids in price, nutrition, and even food safety aspect, and also paving the way for species adulteration.

In this study, the molecularly imprinted nano-polymer of minocycline was polymerized on the surface of a metal organic framework material to synthesize a novel composite. This composite was used as absorbent to develop a dispersive solid phase microextraction method for extraction of 7 tetracyclines in chicken muscle followed by determination with ultra performance liquid chromatography.

Food-borne diseases are widespread; one of the reasons is contamination with staphylococcal pathogens that can produce enterotoxins of the protein, causing numerous diseases in humans. The long-term stability of the toxins requires that the methods for foodstuff quality control be refined to prevent contamination with staphylococcal enterotoxins.

In this study, a real-time loop-mediated isothermal amplification (Rti-LAMP) combined with immunomagnetic beads separation (IMS) assay and SDS rinse was developed for the rapid and sensitive detection of Salmonella in ready-to-eat (RTE) meat without prior enrichment. Polyclonal antibody and specific immunomagnetic beads (IMBs) for Salmonella flagellum were prepared.

In 2018, the European Food Safety Authority reiterated the need for continued monitoring and reduction of opium alkaloid contamination on culinary poppy seeds. In this study, we propose acidic potassium permanganate chemiluminescence as an alternative detection strategy for the selective determination of morphine on poppy seeds. Six different brands of poppy seed purchased in Australia were found to contain, on average, between 21 and 210 μg/g of morphine.