Residues In Food Research Articles

Secondary metabolites of Santolina africana: chemical profiles and assessment of biological activities

Chemicals and antibiotics are serious problems that cause the resistance of bacteria and the persistence of chemical residues in food. These chemical products affect human health and promote diseases. Therefore, the use of natural resources, especially plants, appears as an alternative to avoid the harmful impacts of such products. Plant active substances such as essential oils, alkaloids and phenols are of great interest to scientists and have been studied for their biological activities. Essential oils (Eos) from the stems of Santolina africana were extracted by hydrodistillation and analyzed by Gaz Chromatography/ Mass Spectrometry (GC-MS). The antioxidant activity of crude extracts and Eos was evaluated by the DPPH assay and the antibacterial activity was evaluated by the disc diffusion method and the broth microdilution method against Gram-positive strains (Bacillus subtilis, Staphylococcus aureus) and Gram-negative strains (Escherichia coli, Salmonella paratyphi, and Pseudomonas aeruginosa). S.africana Eos from Morocco and Tunisia were found to be rich in artemisia ketone (35.4% and 44.3%, respectively), santolina alcohol (16.2%and 3.2%, respectively) and isoborneol (6.1% and 26.6%, respectively). Methanol extracts were rich in phenolic and flavonoids contents and showed the highest DPPH radical scavenging activity. Results exhibited the sensitivity of the strains to essential oils from S. africana especially against Gram-positive bacteria. This current research will provide new information about this plant that can be used as a natural antioxidant and antibacterial for industrial purposes.

Antibody Production, Immunoassay Establishment, and Specificity Study for Flunixin and 5-Hydroxyflunixin.

Flunixin (FLU) is a nonsteroidal drug that is widely used in animals, causing severe drug residues in animal-derived foods and environment. The development of antibody-based rapid immunoassay methods is of great significance for the monitoring of FLU and its metabolite 5-hydroxyflunixin (5-FLU). We prepared monoclonal antibodies (mAbs) with different recognition spectra through FLU-keyhole limpet hemocyanin conjugates as immunogen coupled with antibody screening strategies. mAb5E6 and mAb6D7 recognized FLU with high affinity, and mAb2H5 and mAb4A4 recognized FLU and 5-FLU with broad specificity. Through evaluating the recognition of these mAbs against more than 11 structural analogues and employing computational chemistry, molecular docking, and molecular dynamics methodologies, we preliminarily determined the recognition epitope and recognition mechanism of these mAbs. Finally, an indirect competitive enzyme-linked immunosorbent assay for FLU based on mAb6D7 was developed, which exhibited limits of detection as low as 0.016-0.042 μg kg -1 (L-1) in milk and muscle samples.

Allergies in the light of global environmental changes

The increase in allergies began worldwide with the onset of the Great Acceleration. Environmental pollution and climate change now threaten to cancel out decades of success in health research. Asummary of environmental influences is provided, which not only shows the significant increase in the prevalence of allergies worldwide but also that of noncommunicable diseases. The effects of the climate crisis on allergies and the multifactorial and interfunctional relationships with other environmental changes are described in detail. In order to obtain an overview of the possible effects of global environmental changes on allergies, awide range of literature was evaluated and the study results were prepared and summarized. Alarge number of allergens are influencing the human exposome on adaily basis. These allergens are triggered by environmental changes, such as air pollution in the ambient air and indoors, chemicals in everyday objects or residues in food. People are sensitized by the interaction of allergens and pollutants. The prevalence of allergies is stagnating in industrialized countries. This is probably just the calm before the storm. The accelerating effects of global warming could make pollen and air pollutants even more aggressive in the future. Urgent action is therefore needed to minimize environmental pollution and mitigate climate change.

Semistable emulsion assisted dispersive liquid–liquid microextraction for the determination of fungicide residues via HPLC

Fungicide residues in food can pose serious hazards to humans. The aim of this study was to establish a new method of semistable emulsion assisted dispersive liquid–liquid microextraction (DLLME) for the preconcentration and determination of fungicide residues in juice samples. In this study, Gum Acacia (GA) was selected as the dispersive agent and decanoic acid was adopted as the extractant in aqueous sample. Based on that, a semistable emulsion was induced to facilitate the extraction of target analytes and automatic phase separation. The mechanistic analysis results revealed that the formation of the semistable emulsion was attributed to the mild emulsification of GA with a high molecular weight. Besides, the semistable emulsiont allowed the automatic phase separation in DLLME for the first time. Moreover, the novel method was optimized for detecting fungicide residues and exhibited good linearity (R2 ≥ 0.995), precision (≤16.2 %), matrix effect (≤9.8 %), method recovery (84.0–103.6 %), as well as a low limit of detection (0.5–2.5 μg·L−1) and quantitation (1–5 μg·L−1). In conclusion, this method can be employed to effectively measure fungicide residues in juice samples (orange, grape, carrot and peach). Furthermore, this method can be considered as an effective DLLME alternative for the automatic pretreatment of samples, exhibiting a promising application prospect in food safety.

Simultaneous and rapid determination of lomefloxacin and chlortetracycline hydrochloride residues in meat foods by Al3+ sensitized synchronous fluorescence spectrometry

The fluorescence intensity of lomefloxacin and chlortetracycline hydrochloride were significantly enhanced after the complexation of the two antibiotics with Al3+ and the synchronous fluorescence spectra of the two complexes could be well separated when Δλ = 70 nm. Based on the above facts, a new method combining Al3+ sensitization with synchronous fluorescence spectrometry was developed to determine lomefloxacin and chlortetracycline hydrochloride residues in meat foods in this study. This study showed that the concentration of the two antibiotics had an excellent linear relationship with the synchronous fluorescence intensity in the range of 1–550 ng mL−1 and 5–1800 ng mL−1. Detection limits of the two antibiotics were 0.0378 μg kg−1 and 0.3530 μg kg−1, respectively. Recovery rates for lomefloxacin and chlortetracycline hydrochloride were 86.1 - 90.2% and 85.3 - 96.5% in meat samples, respectively. The novel synchronous fluorescence spectrometry established in the experiment had the advantages of high sensitivity, good selectivity, low detection limit, fast detection speed and high accuracy. It had been applied to the detection of lomefloxacin and chlortetracycline hydrochloride residues in meat with satisfactory results.

Development of a competitive array for discriminative determination of amphenicols in egg based on ribosomal protein L16

Abstract Object The amphenicols (chloramphenicol, thiamphenicol and florfenicol) can cause aplastic anaemia and other severe side effects to the consumers, so it is very necessary to inspect their residues in foods of animal origin. However, there has been no paper reporting the use of amphenicols receptor for the determination of their residues, and all the previously reported immunoassays for amphenicols can not differentiate the specific species. Materials and Methods In this study, the ribosomal protein L16 of Escherichia coli was first expressed, and its intermolecular interaction mechanisms with the three amphenicols were studied by using molecular docking technique. Then the protein was combined with three enzyme labeled conjugates to develop a direct competitive array on microplate for determination of the three drugs in egg. Results Due to the use of principal component analysis to analyze the data, this method could discriminate the three drugs in the range of 0.1-10 ng/mL, and the limits of detection for the three drugs were in the range of 0.0002-0.0009 ng/mL. The analysis results for the unknown egg samples were consistent with a liquid chromatography tandem mass spectrometry method, and the method performances were superior to the previous immunoassays for amphenicols. Conclusion This is the first paper reporting the use of ribosomal protein L16 to develop a competitive array for discriminative determination of amphenicols in food sample.

SURVEY OF TETRACYCLINES RESIDUES IN BRAZILIAN SWINE MUSCLE

The use of antibiotics is still intensive in animal production. Among the most used veterinary products in pig farming, tetracyclines can be highlighted. When used in excess, these substances can leave residues in food, which depending on the concentration pose a risk on consumers. Brazil, as one of the world’s largest producer and exporter of animal protein, must be attentive to the laws and ensure that their meat products are safe for human health. So, the concentration of veterinary residues eventually detected must be below the maximum residue limits (MRLs) stipulated by the regulatory agencies. To contribute with subsidies for decision making in pork safety to the annual monitoring program, performed by the Ministry of Agriculture and Livestock, this study aimed to evaluate the residues of tetracyclines in swine muscle from the federal inspection system, by validated and officially accepted analytical methodology (HPLC-UV). Any suspect results obtained from the HPLC-UV analysis can be confirmed immediately by injecting the samples onto a LC-MS/MS system. The results showed that all evaluated samples had concentrations of tetracycline residues below the MRL, and therefore, can be considered safe for human consumption.

Avaliação da modulação do manejo integrado de pragas para mitigação de resíduos de pesticidas em manga

ABSTRACT The increase of pesticide residues in food is extremely dangerous for humans. This research aimed to determine the concentrations of left-over pesticides residues on mangoes after they were exposed to pesticide residue mitigation modules (PRMM). Among these, four modules were used as candidate for integrated pest management approaches, while the fifth was traditional and served as a control. Residues of the lambda-cyhalothrin, cypermethrin, indoxacarb, imidacloprid, pyriproxyfen, acetamiprid, buprofezin and chlorpyrifos pesticides were assessed from mangoes taken from orchards. The QuEChERS technique was used to extract the residue samples and the GC-MS for their quantification. A significant increase in the percentage of contaminated samples was recorded during the 2019-2020 and 2020-2021 growing seasons. Samples belonging to PRMM-I showed 16.67 % (2019-2020) and 25.29 % (2020-2021) of contamination over the control. The samples collected during 2019-2020 and 2020-2021 from PRMM-II showed, respectively, 58.13 and 53.13 % of contamination. During 2020-2021, 66.67 and 67.00 % of the samples were contaminated for PRMM-III and PRMM-IV, respectively. Recoveries ranged from 88.37 to 99.02 %, with 1.07 to 3.97 % relative standard deviation, for all samples, in both seasons. PRMM-IV showed a greater contamination than the other modules and the control.

Etched stainless steel wire modified with conjugated microporous polymers-F6 for jacket-free stir bar sorptive extraction of benzoylureas in juice sample.

Benzoylurea (BU) insecticides have been widely used for pest control as third-generation insecticides. Considering that their residues in food may cause adverse effects on human health, the upper limits of BUs remaining in food have been set by the administration. Therefore, it is essential to develop a sensitive and efficient analytical method to determine the residues of BUs in food. Stir bar sorptive extraction (SBSE) is a novel sample preparation technique, and stainless steel wire (SSW) is an ideal substrate for an SBSE device. In this work, a novel SBSE device of SSW jacket-free stir bar with a dumbbell shape was designed and prepared. The conjugated microporous polymer CMP-F6, which possesses a porous structure, high hydrophobicity and rich fluorine-containing functional groups, was immobilized on the surface of SSW by the method of polyacrylonitrile glue adhesion. Compared with previous studies, which used SSW as a substrate, the method of etching partial SSW with hydrochloric acid, on the one hand, made the surface of SSW rough and easy to modify the extraction coating, and on the other hand, converted itself into a dumbbell-shaped structure, which is conducive to improving the extraction efficiency and stability of the SBSE device. The method of SBSE-HPLC-UV was established for determining five BUs. Owing to the hydrophobic interaction and F-F interaction between CMP-F6 and analytes, this method showed good extraction efficiency and had good linearity (R2 ≥ 0.9945) and high sensitivity (LODs in the range of 0.1-0.2 ng mL-1). It was used for the analysis of benzoylurea in an apple juice sample, and the recoveries were 74.3-117.9%.

A new plant-esterase inhibition based electrochemical sensor with signal amplification by MoS2@N-CDs for chlorpyrifos detection.

Chlorpyrifos (CPF) is the most common pesticide entering the food chain and posing a threat to human health. This study presents a new electrochemical biosensor based on molybdenum disulfide nanosheets and nitrogen-doped carbon dot nanocomposite (MoS2@N-CDs) and kidney bean esterase (KdBE), and it is shown to achieve accurate detection of CPF. MoS2@N-CDs were prepared by a facile solvothermal method and characterized by electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Electrochemical characterization confirmed that MoS2@N-CDs facilitated electron transfer and increased the electroactive surface area of the electrode, thereby improved the sensing performance of the electrode. The oxidation peak current of 1-naphthol, which was produced by the hydrolysis of 1-naphthyl acetate catalyzed by KdBE, was adopted as the signal of the sensor. CPF can suppress KdBE activity and consequently cause a decrease in the sensing signal. The experimental results show that the variation of sensing signal is a reliable index to evaluate the CPF level. Under the optimized conditions, the developed enzyme sensor showed superior CPF assay performance with a linear detection range as wide as 0.01-500 μg L-1 and LOD as low as 3.5 × 10-3 μg L-1 (S/N = 3). The inter- and intra-batch RSDs for electrode testing were 4.02% and 2.69%, respectively. Moreover, the developed biosensor also showed good stability and anti-interference. The spiked recoveries of CPF in oilseed rape and cabbage ranged from 98.09% to 106.01% with low relative standard deviation (RSD) (<5.23%), suggesting that the sensor is a promising tool to enable simple, low-cost but highly sensitive large-scale screening of CPF residues in food.

Assessing the performance of various sorbents in micro-solid phase extraction cartridges for pesticide residue analysis in feed.

Newly designed micro-solid phase extraction cartridges are now available, reflecting the increasing shift towards laboratory automation, especially in the clean-up step for the analysis of pesticide residues in food and feed. In the present study, the introduction of different sorbents on the newly designed PAL µSPE CTC cartridges was investigated for the removal of matrix interferents and the recovery of pesticides. Eight cartridges containing different sorbent combinations and different amounts were used including EMR-lipid (not activated), Z-sep, chitin, C18, PSA, and GCB. The evaluation of co-extractive removal for each cartridge showed that the optimal choice for removing fatty acids was the cartridges containing PSA and Z-sep as clean-up sorbents. However, the presence of C18 and EMR-lipid was still required for the removal of sterols and tocopherols. Two grams of sample, fish feed (FF) and rapeseed cake (RSC) were extracted using QuEChERS citrate buffer, followed by a freeze-out step. The recoveries and repeatability of QuEChERS using µ-SPE clean-up were evaluated for 216 pesticide residues (112 compounds analyzed by GC-MS/MS and 143 compounds by LC-MS/MS, from which 39 compounds were analyzed using both techniques). The best results, with recovery between 70 and 120% and RSD <20%, were achieved when FF samples were cleaned-up with 15 mg EMR-lipid and 20 mg MgSO4. This was achieved for 94% of GC-amenable compounds and 86% of LC-amenable compounds. In the case of RSC, the best results were seen when samples were cleaned-up with the cartridge containing only 20 mg Z-sep and 20 mg MgSO4. This was achieved for 88% of GC-amenable compounds and 90% of LC-amenable compounds. Although these cartridges yielded optimal results in terms of recovery, their use could require more instrument maintenance, especially for GC-MS/MS, due to the lower removal of co-extractives.

Detection of carbofuran in fruits and vegetables by Raman spectroscopy combined with immunochromatography.

It has long been desired to develop rapid methods for the rapid identification and quantification of pesticides and their metabolites. Carbofuran, a representative pesticide of the carbamate group, is highly systemic and is used on vegetables, fruits and grains, which has led many countries to test for residues in food and the environment. In this study, gold and silver composite core-shell (Au@Ag) nanoparticles were used to label the carbofuran antibody and Raman molecule 5,5-dithiobis-2-nitrobenzoic acid (DTNB) to synthesize Raman immune probes. The signal value of DTNB was read using a Raman spectrometer, and the quantitative detection technology of carbofuran was established based on lateral flow immunochromatographic assay (ICA) combined with surface-enhanced Raman spectroscopy (SERS). SERS-ICA is a rapid, quantitative and ultrasensitive test for the determination of carbofuran in fruits and vegetables with a sensitivity of 0.1 pg mL-1. Consequently, the results demonstrate that the SERS-based lateral flow immunosensor developed in this study has the advantages of excellent assay sensitivity and remarkable multiplexing capability, and thus it will have great application potential in food safety monitoring.

Comparison of different fast gas chromatography - mass spectrometry techniques (Cold EI, MS/MS, and HRMS) for the analysis of pyrethroid insecticide residues in food.

In the multiclass, multiresidue analysis of pesticides in food and environmental samples, pyrethroid insecticides are generally more difficult to analyze than other types of analytes. They do not ionize well by electrospray ionization, and although they are suitable for analysis by gas chromatography-mass spectrometry (GC-MS), selectivity using standard electron ionization (EI) in GC-MS is often insufficient because the molecular ion is rarely present. Many pyrethroids tend to have the same fragment ions in MS or high-resolution (HR)MS, and similar ion transitions in tandem MS/MS, leading to difficulties in distinguishing different pyrethroids from each other and chemical interferences in complex matrices. In this study, different forms of fast GC coupled with different types of MS detectors were compared for the analysis of up to 15 pyrethroids in barley extracts as a test case to assess which approach was the most advantageous. The three studied GC-MS techniques consisted of Cold EI using supersonic molecular beams in selected ion monitoring (SIM) mode with a single quadrupole instrument; triple quadrupole MS/MS; and HRMS using an orbital ion trap (orbitrap). A higher flow rate was used in Cold EI, and low pressure (LP) GC was employed in the MS/MS and orbitrap methods, to speed up the GC analyses (<10 min chromatograms in all cases). Each technique had some advantages over the others depending on specific pyrethroid analytes in the matrix. Nontargeted LPGC-orbitrap typically yielded the highest selectivity, but it rarely achieved the needed detectability to quantidentify the residues at 10 ng g-1. Cold EI-SIM and LPGC-MS/MS usually met the needed detection limits and generally achieved similar capabilities for the targeted pyrethroids.

Determination of 118 pesticide residues in urine by ultra-high performance liquid chromatography-tandem mass spectrometry

Pesticide residues in food and their hazardous effects have attracted much attention given the increased and widespread use of pesticides. The long-term consumption of food containing pesticide residues is an important pathway for the gradual accumulation of pesticides in the human body. Urine is often monitored as a biological sample for low-dose exposure to pesticides, and urine collection is a relatively convenient sampling technique in general population research. In order to effectively monitor residual levels of multiple pesticides in human urine and provide an important technological approach for health risk assessment, a rapid screening and confirmatory detection method for 118 pesticides in urine was established using QuEChERS method as a pretreatment combined with ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-MS/MS). The 118 pesticides analyzed included organophosphorus, carbamate, neonicotinoid, and strobilurin fungicides and other widely used pesticides. Following systematic optimization of the pretreatment process, LC separation conditions, and MS/MS parameters, 118 pesticides were extracted from urine samples and analyzed within 2 h. In brief, the target analytes in 5 mL urine samples were extracted with 10 mL of acetonitrile and added with 5 g of anhydrous MgSO4 and 1 g of NaCl as water-removal and salting-out agents, respectively. After centrifugation, 6 mL of the supernatant was cleaned using the QuEChERS method with 300 mg of C18, 300 mg of primary secondary amine (PSA) and 900 mg of anhydrous MgSO4 as the purification adsorbent. After nitrogen blowing and solubilization, the 118 target analytes were separated on a ZORBAX Eclipse Plus C18 analytical chromatographic column (100 mm×2.1 mm, 1.8 μm) with gradient elution using (A) 0.01% formic acid aqueous solution (containing 2 mmol/L ammonium formate) and (B) 0.01% formic acid methanol solution (containing 2 mmol/L ammonium formate) as mobile phases. The gradient elution program was as follows: 0-0.5 min, 5%B; 0.5-1.5 min, 5%B-20%B; 1.5-2.5 min, 20%B-50%B; 2.5-8.0 min, 50%B-80%B; 8.0-9.0 min, 80%B-98%B; 9.0-11.0 min, 98%B; 11.0-11.5 min, 98%B-5%B; 11.5-15.0 min, 5%B. The analytes were then determined by UHPLC-MS/MS with positive/negative ion switching in dynamic multiple-reaction monitoring mode and quantified using the external standard method. The results indicated that the proposed method can determine 118 pesticides in urine simultaneously and rapidly. The limits of detection and limits of quantification were 0.10 and 0.50 μg/L, respectively, and the matrix effects were less than 20%for all targeted compounds. The recoveries of the 118 pesticides in urine were between 70.2% and 104% at three spiked levels of 0.50, 1.00, and 5.00 μg/L, and the relative standard deviations ranged from 2.8% to 9.3%. The method was applied to 10 actual urine samples, and the results revealed the presence of six pesticides, including thiamethoxam, clothianidin, acetamiprid, dinotefuran, isoproturon, and dimethomorph, with contents ranging from <LOQ to 3.65 μg/L. Thiamethoxam and clothianidin were detected most often in the samples, and their concentrations were highly correlated with the current use of these pesticides in edible agricultural products. The proposed method has the characteristics of high efficiency, sensitivity, and accuracy and is suitable for the rapid screening and determination of the 118 pesticide residues in human urine samples.

The determination of 11 sulfonamide antibiotics in water and foods by developing a N-rich magnetic covalent organic framework combined with ultra-high performance liquid chromatography-tandem mass spectrometry.

The concentration of antibiotic residues in water and animal-derived foods is low and the matrix is complex, and effective extraction of antibiotic residues in them is a key factor for accurate quantification. It is important to establish a rapid and effective method for the analytical determination of antibiotics in water and foods. In this study, a type of novel magnetic COF (Fe3O4@SiO2@PDE-TAPB-COF) was synthesized and characterized. Moreover, Fe3O4@SiO2@PDE-TAPB-COF combined with ultra-high performance liquid chromatography-tandem mass spectrometry was used to determine the 11 sulfonamide antibiotics (SAs) in water and food. The parameters including pH, adsorption amount, adsorption time, type of elution solvent and elution time were optimized. Under the optimal conditions, the standard curves of 11 SAs showed good linearity (R 2 > 0.999) in their respective concentration ranges and had lower detection and quantification limits. The spiked recoveries of the developed MSPE-UPLC-MS/MS method for the 11 SAs in water and foods were 74.3-107.2% and 75.1-102.5%, respectively. And the relative standard deviations (RSDs) were less than 9.56% (n = 7). The results indicated that the method can be used for the determination of SAs in foods and water with low detection limits and high sensitivity.

Rapid Determination of 53 Stimulants Residues in Animal Food by Ultra-high Liquid Chromatography Tandem Mass Spectrometry

Rapid Determination of 53 Stimulants Residues in Animal Food by Ultra-high Liquid Chromatography Tandem Mass Spectrometry

Impacts of the Environmental Pollution Residues in Human Food on the Public Health

The environmental pollution Polychlorinated dibenzo-p-dioxins, the polychlorinated dibenzofurans PCDD/F and the polychlorinated biphenyls (PCB) contamination in the food from the animal origin were caused by the industrially produced feed from the free range chicken, sheep, and beef. To elucidate the entry of the the environmental pollution polychlorinated biphenyls (PCBs) and the Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans PCDD/Fs in the food related to the environmental contamination. The food products from the farm animals are sensitive to the environmental pollution dioxin/ polychlorinated biphenyls (PCB) exposure, the suckling calves and the laying hens housed outdoor at the soil concentrations that have previously been considered as safe. In the beef/veal when the soil is contaminated. The eggs/ the broiler, this can occur. The eggs consumer's especially the young children can easily exceed the health-based guidance values, the tolerable daily intake. The soil, the chicken eggs exposure pathway is probably the most sensitive route for the human exposure to both the environmental pollution dioxin-like polychlorinated biphenyls and the PCDD/Fs from the soil and needs to be considered for the soil guidelines. The calves from the suckler cow herds are the most prone to the impacts of the dlPCB contamination due to the excretion/accumulation via the milk. The environmental pollution polychlorinated biphenyls (PCB) (and the PCDD/F) intake for the free-range cattle stems from the feed and the soil. The sources for the PCDD/Fs and polychlorinated biphenyls (PCBs) relevant to the environmental contamination in polychlorinated biphenyls respect to the food safety. It also includes the considerations on the assessment of the emerging persistent organic pollutants. The major sources of the environmental pollution PCDD/F and the dl-PCB contamination of the food of the animal origin are the soils contaminated from the polychlorinated biphenyls (PCB) and the PCDD/F releases; the polychlorinated biphenyls (PCBs) emitted from the buildings and the constructions; the environmental pollution polychlorinated biphenyls (PCBs) present at the farms. The impacted areas need to be assessed with the respect to the potential contamination of the food producing animals. The livestock management techniques can reduce the exposure to the environmental pollution PCDD/Fs and the environmental pollution polychlorinated biphenyls (PCBs). The control and the reduction measures are recommended for the emission sources and the new listed and the emerging persistent organic pollutants to ensure the food safety.

Mechanisms of piperonyl butoxide cytotoxicity and its enhancement with imidacloprid and metals in Chinese hamster ovary cells

The widespread use of chemicals and the presence of chemical and metal residues in various foods, beverages, and other consumables have raised concerns about the potential for enhanced toxicity. This study assessed the cytotoxic effects of Piperonyl butoxide (PBO) and its enhancement by combination with major contamination chemicals including Imidacloprid and metals, using different cytotoxic and genotoxic assays in Chinese hamster ovary (CHO) cells. PBO exhibited elevated cytotoxic effects in poly (ADP-ribose) polymerase (PARP) deficient CHO mutants but not in Glutathione S-transferase deficient CHO mutants. PBO cytotoxicity was enhanced by PARP inhibitor, Olaparib. PBO cytotoxicity was also enhanced with co-exposure to Imidacloprid, Lead Chloride, or Sodium Selenite. PBO induces γH2AX foci formation and apoptosis. The induction of DNA damage markers was elevated with PARP deficiency and co-exposure to Imidacloprid, Lead Chloride, or Sodium Selenite. Moreover, PBO triggers to form etch pits on plastic surfaces. These results revealed novel mechanisms of PBO cytotoxicity associated with PARP and synergistic effects with other environmental pollutants. The toxicological mechanisms underlying exposure to various combinations at different concentrations, including concentrations below the permitted limit of intake or the level of concern, require further study.

Enhanced detection of acetamiprid via a gold nanoparticle-based colorimetric aptasensor integrated with a hybridization chain reaction.

This study presents a novel colorimetric aptasensor, which seamlessly integrates gold nanoparticles (AuNPs) with the amplification potential of the hybridization chain reaction (HCR) for enhanced detection of acetamiprid. The aptamer, hybridized with a partially complementary strand that is covalently linked to AuNPs, serves as the recognition element for acetamiprid. The free end sequence of the aptamer, distal from the AuNP surface, functions as the initiating strand for the HCR, triggering the amplification process. In the absence of acetamiprid, the HCR efficiently occurs, conferring robust salt tolerance to the AuNPs and maintaining their characteristic red coloration. However, in the presence of acetamiprid, the aptamer preferentially binds to its target, disrupting the double-stranded structure and leading to the dissociation of the aptamer from the AuNPs. This dissociation results in a decrease in the HCR product, subsequently diminishing the salt tolerance of AuNPs and triggering a colorimetric transition from red to gray. This integration enhances sensitivity to 3.14 nM. Additionally, carbon quantum dots (CQDs) transduce colorimetric signals to fluorescent ones, further boosting the sensitivity to 0.24 nM. The aptasensor exhibits excellent selectivity and robustness. Real-world testing on tomato, peach, and lettuce shows recoveries of 98.50% to 100.36% with low standard deviations, validating its utility for pesticide residue analysis and food safety. This study provides a powerful tool for rapid and accurate pesticide detection, crucial for food safety.

A circular economy for reusable plastic packaging: digital assessment for cleaning assurance

Single use plastic packaging is widely accepted to cause significant negative environmental impacts. One option to reduce these impacts is to develop commercially viable and socially acceptable reuse systems. Such closed loop packaging systems require careful consideration of reverse (or circular) logistics, financial modelling, and quality control (fulfilling legal requirements and ethical obligations). One of the most prominent barriers to the concept of reusable packaging for food is safety, dictated by challenges of effective cleaning and pack integrity assessment. This research directly addresses cleaning assurance by investigating the application of ultraviolet (UV) induced fluorescence imaging to optically detect residual food fouling on plastic packaging surfaces. This research reports for the first time the evaluation of UV fluorescence imaging @370 nm for the detection of food fouling on washed PET food pots. The technique is compared against the industry standard, adenosine triphosphate swabbing, and is found to provide a comparable range of sensitivity, full surface coverage, faster assessment, and is suitable for full automation without the use of consumables. The technique is evaluated with respect to integration into industrial process systems. Plastic packing design implications are discussed in this context.