Research Publications (Food Safety)

Singlet oxygen (1O2), an initiator for photooxidation, is responsible for vegetable oil degradation. However, few details about the formation of 1O2 in vegetable oil are known due to the lack of a reliable method for its determination. In this study, a simple, reliable, and sensitive high-performance liquid chromatography (HPLC) method for indirect quantification of 1O2 generated in vegetable oil was developed. Furfuryl alcohol (FFA) was selected as a real-time “trap” for 1O2.

The dual-mode sensing strategy not only has the inherent characteristics of each response mode but also can mutually verify the detection results obtained by different modes, which will effectively improve the accuracy and reliability of detection. The electrochemical-photothermal dual mode not only has two mode signals, but also has the advantages of fast response, high sensitivity, good selectivity, low cost, and simple operation.

India has achieved its food security through the green revolution and technological revolution, although food safety is still not realized. Subsequently, agricultural runoffs, industrial wastes and domestic sewages continuously contaminate the water and the associated livelihood through several contaminants. Pesticides and their residues, which function as endocrine disrupting chemicals (EDCs), influence the food web through water resources, among other things.

Salmonella is one of the most common food-borne pathogens, and the food safety problem caused by Salmonella has raised concern globally. In this work, a novel electrochemical biosensor based on single primer isothermal amplification (SPIA) was established for the specific and sensitive detection of Salmonella.

Macrocyclic lactones (MLs) are widely used as antiparasitic agents in the livestock, monensin (ionophore antibiotics) is recommended in cattle feed as growth-promoting additives, and fipronil is a drug prescripted in animal production to control ectoparasitic infestations. However, the use of these drugs in food-producing animals may lead to the appearance of their residues in meat and offals.

Fungicides are applied from plant development to grape production, transport, and storage. Even after fruit processing, residues of these compounds can be present in grape by-products such as wine and juice.

In this study, we developed an efficient method based on magnetic Fe3O4-modified graphene oxide (MNPs@GO) along with aptamer-functionalized upconversion nanoparticles (UCNPs) for Staphylococcus aureus detection. MNPs@GO are prepared using aptamer-functionalized MNPs and GO by means of π-π stacking interaction. In the absence of Staphylococcus aureus, MNPs@GO are formed and are magnetically separated.

Zearalenone (ZEN), which is usually generated by Fusarium species, is common contamination of corn. ZEN induces estrogen effects and disrupts the reproductive system of humans and animals. Herein, we established a method of quantum dots (QDs) immunochromatographic test strips for the detection of ZEN. In this method, QDs (Q2605, G2701A) and anti-ZEN monoclonal antibodies were conjugated by carbodiimide.

A fluorescence immunochromatographic strip using quantum dot nanobeads (QDNBs)-monoclonal antibody (McAb) conjugates was developed to rapidly detecting okadaic acid (OA) in shellfish. Under optimal conditions, the linear working range was 0.62–20 ng·mL−1, and the full competitive limit of detection (LOD) was 20 ng·mL−1, corresponding to 160 μg·kg−1 per shellfish, meeting the regulatory limit of European Conformity (EC).

Norfloxacin is an antibiotic in the fluoroquinolone family licenced for use in animals. However, residues in animal products can have negative consequences for consumers. As a result, residue detection in various food matrices must be considered. Norfloxacin accumulates in animal-derived foods, causing deleterious consequences in humans such as foetal deformity, renal failure and drug resistance.

The electrochemical immunosensor is one of the most promising detection approaches for pathogenic microorganism. In this study, a label-free electrochemical immunosensor based on chitosan/gelatin was fabricated for the detection of Bacillus cereus. Anti-Bacillus cereus polyclonal antibodies were immobilized through a cross-linking method on a chitosan/gelatin-modified electrode.

A programmed, autonomous, and self-powered DNA motor was developed for one-step amplification detection of ochratoxin A (OTA). The OTA can bind with the aptamer of hairpin and induce the opening of hairpin. Then, the Mg2+-specific DNAzyme can circularly cleave the fluorophore-labeled DNA on the gold nanoparticles (AuNPs), causing autonomous and processive movement of DNA motor.

The most commonly reported serotype of Shiga toxin-producing Escherichia coli (STEC) is O157:H7. This pathogen presents a threat to public health and is a cause of foodborne illness worldwide. The efficient and sensitive detection of E. coli O157:H7 remains a challenge for food safety. In this report, we developed a sensitive and specific loop-mediated isothermal amplification (LAMP) reaction coupled with a lateral flow (LF) assay to rapidly detect E. coli O157:H7.

A novel sandwich strategy based on the dual recognition by teicoplanin (Teic) and IgG was developed for the rapid separation and identification of Staphylococcus aureus.

Escherichia coli O157 (E. coli O157) is one of the most dangerous foodborne pathogens worldwide. A convenient, sensitive, and specific method for the E. coli O157 detection is necessary. The present study developed an isothermal real-time recombinase polymerase amplification (real-time RPA) assay and an RPA combined with lateral flow strip (LFS-RPA) to detect E. coli O157 targeting the conserved region of the rfbE gene.

Harmful secondary metabolites produced by fungi, mycotoxins, are found worldwide in a multitude of products. Roquefortine C (ROQ-C) is a mycotoxin produced by Penicillium roqueforti, the major fungus used to ripen blue-veined cheeses. To facilitate the screening of cheeses for ROQ-C, a method based upon the ambient ionization technique of direct analysis in real time-mass spectrometry (DART-MS) was developed.

In this study, a recombinase aided amplification (RAA) assay with an improved propidium monoazide (PMAxx) treatment called PMAxx-RAA assay was developed to detect Salmonella in milk. The established method was performed at 39 °C and the detection time was less than 40 min. Compared with traditional detection methods, the PMAxx-RAA assay is fast, sensitive, and specific because of the gene invA that was selected to design unique primers and probes for detection.

Ochratoxin A (OTA) is one of the most common toxins in food and feed, which seriously affects the health of public. Herein, a convenient biosensor for OTA detecting was built based on graphene oxide (GO) and quantum dots-aptamer (QDs-aptamer) in this investigation. The results in our study demonstrated that the constructed biosensor shows excellent sensitivity and highly selectivity for OTA.

In the European Union (EU), Salmonella was the causative agent responsible for almost one in three (30.7%) of all foodborne outbreaks reported by member states during 2018, causing 11,581 cases of illness, which represented an increase of 20.6% compared to 2017.

Agricultural product contamination by endocrine-disrupting compounds (EDCs) residues is an international public health issue and requires continuously stringent administration. A high-throughput biotin-streptavidin-amplified enzyme-linked immunosorbent assay (BA-ELISA) for detection of progesterone (P4) has been established to be applied in determining milk samples.

A novel method based on ultrasonic-assisted aqueous two-phase extraction (UAATPE) coupled with solidifying organic drop-dispersible liquid–liquid microextraction (SOD-DLLME) was developed for simultaneous determination of nine mycotoxins (aflatoxins of B1, B2, G1, G2, and M1, ochratoxin A, zearalenone, deoxynivalenol and patulin) in medicinal and edible foods by high-performance liquid chromatography (HPLC) with diode array detector (DAD) and fluorescence detector (FLD) in series.

Metribuzin is a broad-spectrum herbicide that allows effective weed management in fields but the contamination of metribuzin on the environment and humans is a threat to its application. To better monitor the residue of metribuzin in practical application, an HPLC–MS/MS method for the determination of herbicide metribuzin and its metabolites DA, DK, and DADK residues in potato tuber was developed. The matrix effects were also investigated in this work.

In recent decades safety of food has played a pivotal role from raw material till it reaches the consumer. The food consumed may contain unwanted contaminants, which may impose severe health implications on the consumers. Instrumental techniques like HPLC, GCMS, LCMS, AAS, FTIR, and NIRS detect the contaminants, but the need for low cost, continuous, specific, real-time, and rapid contaminant detection method is required. To meet these essentials, a biosensor stands as a powerful tool.

Developing sensitive assay for pathogen detection is a sustained demand for food scientists, industries, and government. In this study, an ultrasensitive colorimetric lateral flow assay (LFA) was successfully developed for the detection of Salmonella typhimurium (S. typhimurium). Based on cascade enzyme reaction induced by horseradish peroxidase (HRP)-encapsulated starch-based liposome, the sensitivity of the conventional LFA can be dramatically improved.

In this work, gold nanoparticles (AuNPs) and DNA tetrahedral nanostructure (DTN) as a signal probe carrier platform to control the density of aptamers were used to construct an ultrasensitive electrochemical aptasensor (AuNPs-DTN sensor).