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In sports, curcumin, a substance derived from the rhizome of Curcuma longa (turmeric) plant with antioxidant effect 8 times greater than vitamin E, has attracted the attention of scientists because of its potent antioxidant action, since in athletes subjected to intense exercise the—endogenous mechanisms of neutralization of reactive species are saturated. However, the pharmacokinetic characteristics of curcumin do not favor its medicinal use due to its low absorption, accelerated metabolism and rapid systemic elimination. Thus, the determination of plasma levels in supplemented patients is a crucial step in their pharmacodynamic evaluation. Therefore, the objective of this work was to develop and validate an analytical method by HPLC-FLD for curcumin evaluation in plasma of supplemented athletes. Luna column (C18; 150 × 4 mm; 3 µm), acetonitrile: acetic acid pH 3.2 (45:55 to 60:40) as mobile phase, flow rate of 1 mL min−1, excitation at 429/285 nm and emission at 529 nm and injection of 10 µL were the chromatographic conditions used. Plasma samples were extracted using ethylacetate and methanol (95: 5, 500 µL) and estradiol (30 µg mL−1) as internal standard, with subsequent stirring (3 min) and centrifugation (8 min) (triple extraction). The organic fraction was evaporated under N 2 (20 min) and the dried residue reconstituted in acetonitrile. The method was linear between 44 and 261 ng mL−1, showing intra-day (2.05.6%) and inter-day (4.0–5.1%) precision with accuracy and selectiveness (curcumin t R = 8.7 min and internal standard t R = 13.9 min with relative recovery of 83.2%). So, it can be successfully used for curcumin evaluation in plasma samples from supplemented athletes, as well as being an alternative and advantageous method to UV–Vis and MS/MS in bioavailability studies. [ABSTRACT FROM AUTHOR]

This study aimed to establish a reliable method to determine the level of eight biogenic amines in wine using derivatization and modified liquid-liquid extraction with high performance liquid chromatography-fluorescence detector (HPLC-FLD). HPLC separation conditions were optimized to analyze the derivatized biogenic amines. The standard curve of each biogenic amine exhibited a good linearity confirmed by determination coefficient (0.9983–0.9999) under the concentration range of 0.1 to 50.0 mg/L. The intra- and inter-day precision of the mixed standard (15 mg/L) appeared to be 4.86 and 5.22%, respectively. The limit of detection and limit of quantification ranged of 0.001–0.050 mg/L and 0.005–0.167 mg/L, respectively. To achieve the optimal extraction, 1.0 mL of wine sample was derivatized with 1000 μL of dansyl chloride followed by derivatization termination using 100 μL of ammonium hydroxide. The derivatized amines were further extracted with 1.7 mL of acetonitrile and then centrifuged at 10,000 rpm for 5 min. The optimized extraction was further validated in two wine samples spiked with these biogenic amines under three concentration levels (1.0, 5.0, and 10.0 mg/L). The recoveries of these target amines were found to be 73.02 to 111.61%. A total of 57 wine samples were analyzed using this established method to determine their biogenic amines level. It was found that the red wine samples contained higher concentration than the white wines. The predominant biogenic amines found in these wines included putrescine, tyramine, and 2-phenylethylamine. This study could provide a reliable and accurate method on the determination of the concentration of biogenic amines in wine. [ABSTRACT FROM AUTHOR]

In this study, the effect of three essential oils (EOs) – clove oil (CO), thyme oil (TO), and garlic oil (GO), which are generally recognized as safe – on the planktonic growth, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), motility, biofilm formation, and quorum sensing (QS) of Vibrio parahaemolyticus was investigated. All three EOs showed bacteriostatic activity, with MICs in the range 0.02%–0.09% (v/v). CO and TO completely controlled planktonic growth at 0.28% and 0.08% (v/v), which is four times their MIC (4 × MIC), after 10 min, whereas GO completely controlled growth at 0.36% (v/v) (4 × MIC) after treatment for 20 min. V. parahaemolyticus motility was significantly reduced by all three EOs at 4 × MIC (0.28% for CO, 0.08% for TO, and 0.36% for GO), whereas QS was controlled and biofilm formation reduced by all three EOs at 8 × MIC (0.56% for CO, 0.16% for TO, and 0.72% for GO) after 30 min of treatment. These results suggest that CO, TO, and GO have a significant inhibitory effect on V. parahaemolyticus cells in biofilm sand thus represent a promising strategy for improving food safety. These results provide the evidence required to encourage further research into the practical use of the proposed EOs in food preparation processes. [ABSTRACT FROM AUTHOR]

An effective method for the determination of 20 free amino acids in tea samples using 4-(carbazole-9-yl)-benzyl chloroformate (CBBC-Cl) as a derivatization reagent by high-performance liquid chromatography combined with fluorescence detection (HPLC-FLD) has been established. CBBC-Cl quickly derivatized amino acids within 6 min in basic solution (pH 9.0) at room temperature (ca. 25 °C). The maximum excitation and emission wavelengths of the stable derivatives were 290 nm and 370 nm, respectively. The separation of 20 amino acids, including the theanine (THE) derivative, was optimized on a Hypersil BDS-C18 column. Identification of these derivatives was performed via liquid chromatography/electrospray ionization mass spectrometry (LC/ESI/MS) in positive-ion detection mode. Under optimal conditions, excellent linearity for all the amino acids was obtained, with determination coefficients of r2 > 0.9986. The detection limits (LODs) and quantitation limits (LOQs) ranged from 0.13 to 1.5 μg·kg−1 and 0.43 to 4.95 μg·kg−1, respectively. Satisfactory recoveries, ranging from 86.7 to 106.4%, were obtained for all the amino acids in the tea samples. The developed method has been successfully applied to the quantification of 20 amino acids in tea samples. [ABSTRACT FROM AUTHOR]

Disorders of certain branched‐chain amino acids may be associated with the occurrence and development of non‐alcoholic fatty liver disease. Measurement of related branched‐chain amino acid levels could provide a reference for the clinical and scientific research of the non‐alcoholic fatty liver disease. An established HPLC–FLD method was used to quantify aspartic acid, glutamate, glutamine, glycine, taurine, tyrosine, 4‐amino butanoic acid, tryptophan, methionine, valine, phenylalanine, isoleucine and leucine in mouse brain tissue. Brain tissue samples mixed with internal standard (3‐aminobutyric acid) were processed, then derivatized with 2‐O‐phthaldialdehyde, and finally separated on an ODS2 column through gradient elution at a flow rate of 1.0 ml·min−1. The excitation and emission wavelengths were set at 340 and 455 nm, respectively. The mobile phase A was 100% methanol and the mobile phase B consisted of 30 mmol·L−1 sodium acetate (pH 6.8). The injection volume was 20 μl and the single run time was 45 min. Several parameters, accuracy, precision, and stability, were verified and the results showed the established method had good sensitivity and resolution for all of the 13 compounds and internal standard in mouse brain. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a mycotoxin that may be present in various food and feed of plant and animal origin, including chicken meat. In Italy, backyard poultry farming is rather widespread. Animals are raised for meat, eggs and for ornamental purpose, and they are often fed with home-made diets not subject to official controls. The purpose of this study was to evaluate exposure of ornamental and backyard chickens to OTA using biliary ochratoxin A as a biomarker. Therefore, bile samples, in addition to kidney, liver and muscle, were collected from 102 chickens reared in 16 farms located in 6 Italian regions. High-performance liquid chromatography method and fluorimetric detection (HPLC-FLD) analysis were carried out firstly on bile from all animals, and OTA was detected in 12 chickens (concentration range 3.83-170.42 μg/L). Subsequently, the kidneys of these chickens were also analysed, and the mycotoxin was not detected. The analytical detection limits (LODs) of OTA in bile and kidney were 2.1 μg/L and 0.1 μg/kg, respectively. In conclusion, these animals were exposed to OTA but their meat can be considered safe, given that this mycotoxin, if present, concentrates highest in kidneys. Biliary ochratoxin A confirms its use as a valid biomarker to assess exposure of poultry to OTA. [ABSTRACT FROM AUTHOR]

Purpose: With the present work, we aimed to assess the occurrence of ochratoxigenic fungi and Ochratoxin A (OTA) in dried grapes from Tunisia. Methods: Dried grapes samples (n = 90) were investigated for the presence of ochratoxigenic fungi, which were further characterized at the species level through amplification of the internal transcribed spacer (ITS) region and polymerase chain reaction (PCR) product sequencing. Fungal isolates were tested for their ochratoxigenic potential by high-performance liquid chromatography with fluorescence detection (HPLC-FLD), as well as dried grapes samples after an immunoaffinity column (IAC) clean-up procedure. Results: Black Aspergilli isolates were the dominant genre among the filamentous fungi found in dried grapes samples and were the only OTA-producing fungi encountered. Aspergillus niger aggregate were the most frequently found isolates reaching 70%, 80%, and 85% in dried grapes samples from regions of Kelibia, Sfax, and Rafraf, respectively, while covered 100% of the relevant mycobiota found in imported samples. Aspergillus carbonarius isolates were found only in Sfax’s and Kelibia’s samples, while uniseriate Aspergilli were found between 7 and 20% in dried grapes from Kelibia, Sfax, and the imported samples. The in vitro OTA production test showed that 88.9% of OTA-producing isolates belonged to A. carbonarius with OTA levels varying from 0.06 to 1.32 μg/g of Czapek Yeast Agar (CYA). The remaining OTA-producing fungi (11.1 %) belonged to A. niger aggregate group having a maximum OTA potential of 2.88 μg/g CYA, and no uniseriate Aspergilli isolate was able to produce OTA. All dried grapes samples were free of OTA presence. Conclusion: According to the present study’s findings, no OTA contamination was recorded in the investigated samples from Tunisian market. Nevertheless, the presence of strong OTA producers A. carbonarius in samples originated from the two out of three studied Tunisian regions, as well the high incidences of Aspergillus niger aggregate group with an attested potential for OTA production in all samples, necessitates further research on Tunisian dried grapes. Additionally, a continuous analysis of staple food of the Mediterranean diet is imperative to insure the best quality for the consumers and prevent potential health problems. [ABSTRACT FROM AUTHOR]

Infestation of food crops by fungi has led to serious economic losses in the international market. There is a paucity of information on the multi-mycotoxin profile of cashew nuts from different geographical locations in Nigeria and South Africa. This work aims at comparing the fungal metabolite profile of cashew nut from two African countries using HPLC-FLD and LC-MS/MS. The differences in distribution of the fungal metabolites across the two countries were also examined. A total of 75 (39; Nigeria, 36; South Africa) roasted cashew nuts were purchased from 14 different locations in Nigeria and 10 major supermarkets in South Africa. The samples were subjected to HPLC analysis for aflatoxin and zearalenone and LC-MS/MS analysis for multiple metabolite profiling. Total aflatoxins (0.03-0.77 µg/kg and 0.01-0.28 µg/kg) and zearalenone (123.2 and 788.6 µg/kg) were quantified in nut samples from South Africa and Nigeria, respectively. In contrast, LC-MS/MS analysis showed that none of the major fungi metabolites except for one (citrinin) was present in detectable amount in Nigerian cashew nuts (31.3 μg/kg). Other microbial metabolites present in the nuts were; Aspergillus metabolites (< LOD to 398 × 104 μg/kg and < LOD to 1760 μg/kg); flavoglaucin (5.4-177.4 μg/kg and 45.5-18,368 μg/kg), 7-hydroxykaurenolide (5.5-45.8 μg/kg and 3.5-33.7 μg/kg), chloramphenicol (0.3-4.5 μg/kg) for South African and Nigerian cashew nuts, respectively. The incidence rate of the fusarium toxins beauvericin and bikaverin were higher in Nigerian cashew nut (100% and 17%) than the South African nuts (8% and 8%), 7-Hydroxykaurenolide and chloramphenicol were found in all the cashew nut samples. A total of 15 unspecific metabolites (17-100%) were recorded in the nuts from both countries. Information on the metabolite profile of cashew nuts will provide useful information for policy makers, border agencies and other health-related Institutes. Fungi metabolites profile of Cashew nut from selected locations in Two African Countries. *Roasted cashew nut image- [ABSTRACT FROM AUTHOR]

This survey describes the occurrence and levels of AFs and OTA in chocolate products consumed in Turkey. A total of 130 samples, including bitter chocolate, milk chocolate and chocolate wafers were analysed for these mycotoxins by high-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD). The values of recovery (81–92%) and precision (RSD < 9%) fulfilled the requirements of EC Regulation No. 401/2006. OTA was the most prevalent mycotoxin, with an incidence of 46.7% in bitter chocolate, 22.8% in milk chocolate and 17.4% in chocolate wafers, ranging from 0.18 to 0.75 μg kg−1. AFs were detected in 13.3% of bitter chocolate, in 19.6% of milk chocolate and in 8.7% of chocolate wafers, in concentrations ranging from 0.15 to 2.04 μg kg−1. [ABSTRACT FROM AUTHOR]

Aflatoxin M1 (AFM1) is a 2B Group human carcinogens agent and introduces into the human diet by milk consumption. In the present study 257 raw, 143 pasteurized and 61 UHT milk samples were collected from markets in 117 cities throughout Iran, during winter 2017 and AFM1 contents were determined using a HPLC-FLD method after immunoaffinity clean-up. Mean recovery rates and relative standard deviations of the method were 90.6 ± 5.7%. AFM1 was detected in 252 of 461 (54.7%) samples (mean 31.3 ± 8.8 ng/L), ranging from <10 to 150 ng/L. Three samples (0.6%) exceeded the Iranian maximum limit of 100 ng/L. The mean AFM1 content was significantly higher in raw milk samples obtained from humid climate areas. The extrapolated concentration of AFB1 in dairy cattle feed based on the AFM1 value of milk was 1.96 µg/kg. The AFM1 contamination of milk seems not to be a serious public health concern in Iran. [ABSTRACT FROM AUTHOR]

Supramolecular solvents are nanostructured liquids that are separated from colloidal solutions of amphiphilic compounds as a result of self-assembly of amphiphiles and coacervation under changing conditions. They are considered to be designer solvents as their properties can be tailored to a specific analytical task by controlling the conditions of their formation (amphiphile, coacervation inducer, medium, concentration of components). The discovery of new extraction systems based on supramolecular solvents and their application to relevant analytical tasks are of great importance for the advancement of environmentally-friendly sample preparation. A novel green liquid-phase microextraction approach involving in situ formation of 1-octylamine citrate followed by preconcentration of ochratoxin A from aqueous extract of food sample in supramolecular solvent droplets was developed. The extraction system was carefully characterized. The density of the solvent allowed it to be to retrieved from the extraction system by its solidification. The alkaline nature of the obtained extract allowed the use of acetic acid for its dissolution instead of more toxic organic solvents followed by high-performance liquid chromatography with fluorometric detection. An excellent extraction recovery of 99 % and a satisfactory enrichment factor of 8.3 were achieved. The limit of detection was 0.5 μg kg−1, while the calibration plot was linear over the range of 1.5–50 μg kg−1. Cereal and roasted coffee bean samples were successfully analyzed with a relative bias less than 20 %. In the present work, a phenomenon of supramolecular solvent formation based on primary amine citrate was presented for the first time. Tetrabutylammonium bromide was investigated as a coacervation agent in an extraction system, and possible interactions responsible for its ability to induce phase separation in a micellar solution of primary amine citrate were described. The critical micelle concentration of 1-octylamine citrate in aqueous solution of tetrabutylammonium bromide was firstly determined. [Display omitted] • Primary amine citrate as amphiphilic molecules for SUPRAS phase formation. • Tetrabutylammonium bromide-induced coacervation in primary amine citrate system. • SUPRAS based on 1-octylamine citrate as efficient media for microextraction. • Microextraction of ochratoxin A from food samples followed by HPLC-FLD analysis. • Solidification of SUPRAS phase based on 1-octylamine citrate for extract collection. [ABSTRACT FROM AUTHOR]

Optimizing a multi-residue analysis when using an automatic SPE (solid phase extraction) system and complex matrices becomes a difficult problem because of the large number of experimental factors that can influence the recovery of the analytes. Furthermore, in most cases, the conditions of the factors that enhance the response of one analyte are in conflict with those suitable for some others. In this work, AQbD (Analytical Quality by Design) is applied to the development of an analytical procedure based on automatic SPE coupled to HPLC-FLD in the determination of nine polycyclic aromatic hydrocarbons (PAHs) in coffee samples. Focussing on the SPE, the elution volume, the dry time, and volume in the wash stage, and the organic solvent (at two, three, three, and four levels, respectively) were considered. The first problem is to handle these four factors (control method parameters, CMPs) at different levels to optimize responses (critical quality attributes, CQAs). This task has been carried out using a D-optimal design that, starting from a full factorial design of four factors with 72 experiments, reduced this number to 19, maintaining the precision of the estimates, saving time and costs in the laboratory. The second problem is related to the choice of CQAs to apply the AQbD methodology. A complex matrix such as coffee contains impurities that interferes with the target analytes and may even coelute in the chromatographic determination. A PARAFAC decomposition allows avoiding this problem and uses the "second order advantage" to unequivocally identify each analyte. Then, the obtained sample loadings were used as responses. Specifically, each CQA is the difference between spiked and blank coffee samples. All these CQAs must be maximized. Once the experimental data were obtained, two alternatives were posed: on the one hand, the classical optimization based on the estimation of the effects of CMPs on the CQAs, and on the other hand, applying the AQbD methodology to construct the design space that allows to increase the knowledge of the automatic SPE system. Because the experimental domain of CMPs is discrete and the SPE system performs differently for each analyte, it is not possible to obtain the maximum of all CQAs at the same factor levels. Therefore, the design space of the CMPs is obtaining through the Pareto front of the non-dominated values of CQAs. The nine PAHs selected were phenanthrene (PHE), anthracene (ANT), fluoranthene (FLN), pyrene (PYR), chrysene (CHR), benzo[a]anthracene (BaA), perylene (PER), benzo[b]fluoranthene (BbF) and benzo[a]pyrene (BaP). European regulations amending foodstuff set maximum levels for BaP and the sum of the content of four compounds (PAH4): BaP, BaA, BbF and CHR. • Determination of nine PAHs in coffee by means of automatic SPE coupled to HPLC-FLD. • D-optimal design and PARAFAC useful tools in Analytical Quality by Design. • Multi-response optimization, using a D-optimal design reduces the experimental effort. • Comparison between analysis of effects versus discrete estimate of the design space. • Optimal conditions of automatic SPE selected by means of the useful tool AQbD. [ABSTRACT FROM AUTHOR]

• Magnetic boronic acid hypercrosslinked polymer was prepared via one-pot strategy. • The sorbent possessed good extraction capability for OH-PAHs and catecholamines. • Boronate affinity and π-π stacking played important role in the extraction. • The proposed method provides lower LODs and higher precisions. Urinary hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) and catecholamines (CAs) are important biomarkers of PAHs exposure. In this study, a novel magnetic boronic acid hypercrosslinked composite (Fe 3 O 4 @HCP-BA) is synthesized using a facile one-pot strategy and applied as a sorbent for the simultaneous extraction of OH-PAHs and CAs in urine samples. The synthesized Fe 3 O 4 @HCP-BA composites are characterized by rich pore structure, highly specific surface area, good magnetic response, and excellent selectivity and adsorption efficiency (range: 65.26–496.71 and 1227.3–1581.8 µmol g−1 for CAs and OH-PAHs, respectively). The mechanisms governing the adsorption of the OH-PAHs and CAs to the Fe 3 O 4 @HCP-BA composites were systematically studied via adsorption kinetics, isotherm models, XPS characterization, and molecular simulation. The resultant Fe 3 O 4 @HCP-BA composite-based MSPE/HPLC-FLD method exhibited good linearity (R2 > 0.9916), low limits of detection (0.2–0.3 pg mL−1 and 0.2–0.3 ng mL−1 for OH-PAHs and CAs, respectively), and good precision (intra-day and inter-day RSDs < 11.1%). The analysis of CAs and OH-PAHs in the urine samples from 14 smokers and 14 non-smokers revealed a positive correlation between the concentrations of CAs and OH-PAHs. Our findings not only establish the proposed method as a green, environmentally friendly, and simple strategy for preparing magnetic adsorbents, but also confirm it as a promising alternative method for accurate determination of OH-PAHs and CAs in biological samples. [ABSTRACT FROM AUTHOR]

Biogenic amines (BAs) are low-molecular nitrogenous compounds especially abundant in fermented foodstuff such as wine and cheese, as well as in spoiled products. BAs are bioactive compounds that can cause toxicological problems—e.g., migraines, hypertension, rash, etc.—when ingested in high amounts. Contents of BAs in wines may depend on different factors such as fermentation processes and other oenological practices, as well as on grape quality. This work aims at assessing the evolution of biogenic amines during the manufacturing process of sparkling wines by analysing samples of must, base wines, stabilized wines and 3-month- and 7-month-aged sparkling wines obtained from Pinot Noir and Xarel·lo grape varieties. In addition, the effect of grape quality was also evaluated. The determination of BA contents relies on liquid chromatography with fluorescence detection (HPLC-FLD) with precolumn derivatization of analytes with dansyl chloride. Principal component analysis has been applied to try to extract featured information concerning overall patterns dealing with wine production steps and qualities. The analysis has shown that putrescine is the most abundant amine in this type of samples. Ethanolamine, tyramine, cadaverine and histamine concentrations are also remarkable. Regarding BA formation, their concentrations are quite low in musts, but especially rise after the first alcoholic fermentation. Besides, BA levels are smaller in the products elaborated with grapes of the best qualities, while significantly increase when using grapes of lower qualities.

Cytostatics are toxic pharmaceuticals, whose presence in surfaces puts healthcare workers at risk. These drugs might also end up in hospital effluents (HWW), potentially damaging aquatic ecosystems. Bicalutamide is a cytostatic extensively consumed worldwide, but few analytical methods exist for its quantification and most of them require advanced techniques, such as liquid chromatography mass spectrometry (LC-MS), which are very complex and expensive for large monitoring studies. Therefore, a simple but reliable multi-matrix high performance liquid chromatographic method, with fluorescence detection, was developed and validated to rapidly screen abnormal concentrations of bicalutamide in HWW and relevant contamination levels of bicalutamide in indoor surfaces (>100 pg/cm2), prior to confirmation by LC-MS. The method presents good linearity and relatively low method detection limits (HWW: 0.14 ng/mL; surfaces: 0.28 pg/cm2). Global uncertainty was below 20% for concentrations higher than 25 ng/mL (HWW) and 50 pg/cm2 (surfaces); global uncertainty was little affected by the matrix. Therefore, a multi-matrix assessment could be achieved with this method, thus contributing to a holistic quantification of bicalutamide along the cytostatic circuit. Bicalutamide was not detected in any of the grab samples from a Portuguese hospital, but an enlarged sampling is required to conclude about its occurrence and exposure risks.

Analytical methods using the fluorescence properties of bisphenols (BPA, BPF and BPS) and their complexes with β-cyclodextrin and methyl-β-cyclodextrin were developed. The methods were applied for the analysis of thermal paper and canned food. Their performance was compared with a standard HPLC approach with a diode array and fluorescence detections. For comparison purposes, basic validation parameters (linear range, limit of detection, sensitivity, precision) were evaluated. It was concluded the developed methods facilitate fast and cost-effective determination of three bisphenol species in liquid samples, similar to the HPLC performance. They are also environmentally friendly. BPA, BPF and BPS can be routinely determined with the presented approach.

Hawthorn leaves are a rich source of phenolic compounds that possess beneficial activities for human health. Ultrasonic-assisted extraction (UAE) is an extraction technique frequently used for the isolation of phenolic compounds in plants. Thus, in this study, a Box–Behnken design was used to optimize UAE conditions such as the percentage of acetone, the extraction time and solvent-to-solid ratio (v/w) in order to obtain the maximum content of total compounds by Folin–Ciocalteu and the maximum in vitro antioxidant activity by DPPH, ABTS and FRAP assays in Crataegus monogyna leaves. The optimum conditions to obtain the highest total phenolic content and antioxidant activities were 50% acetone, 55 min and 1/1000 (w/v). A total of 30 phenolic compounds were identified and quantified in C. monogyna leaf extract obtained at these optimum UAE conditions. HPLC-MS allows the identification and quantification of 19 phenolic compounds and NP-HPLC-FLD analyses showed the presence of 11 proanthocyanidins. According to the results, the most concentrated phenolic compounds in C. monogyna leaf extract obtained at optimum UAE conditions were phenolic acid derivatives such as protocatechuic acid-glucoside, dihydroxy benzoic acid pentoside and chlorogenic acid, flavones such as 2″-O-rhamnosyl-C-hexosyl-apigenin, flavonols such as hyperoside and isoquercetin and proanthocyanidins such as monomer and dimer. As a result, the optimized UAE conditions could be used to obtain an extract of C. monogyna leaves enriched with phenolic compounds.

In this research, 42 mesir paste samples produced by a limited number of manufacturers in Manisa, Turkey, were analysed for aflatoxin content by high-performance liquid chromatography with a fluorescence detector after pre-separation using immunoaffinity columns. A good correlation was found with good performance in terms of precision for the method. Limit of detection-limit of quantitation of AFG2-AFB2 and AFG1-AFB1 were 0.05/0.15 and 0.03/0.09 µg/kg, respectively. AFG2, AFG1 and AFB1 were detected in 29%, 71% and 52% samples, whereas AFB2 was not detected in any sample. AFtotal, AFG2, AFG1 and AFB1 content varied between 0.04/10.20 µg/kg, 0.07/0.42 µg/kg, 2.02/10.11 µg/kg and 0.04/0.11 µg/kg, respectively. About 9.5% of samples were found to be above the maxium limit (ML) for AFtotal (10 µg/kg), but none of samples exceeded the ML for AFB1 (5 µg/kg) as set by the European Union for spices. According to the results, it was concluded that traditional products like mesir paste which contains different types of spices should be examined in terms of aflatoxins.

Coffee, one of the most popular drinks around the world, is also one of the beverages most susceptible of being adulterated. Untargeted high-performance liquid chromatography with ultraviolet and fluorescence detection (HPLC-UV-FLD) fingerprinting strategies in combination with chemometrics were employed for the authenticity assessment and fraud quantitation of adulterated coffees involving three different and common adulterants: chicory, barley, and flours. The methodologies were applied after a solid–liquid extraction procedure with a methanol:water 50:50 (v/v) solution as extracting solvent. Chromatographic fingerprints were obtained using a Kinetex® C18 reversed-phase column under gradient elution conditions using 0.1% formic acid aqueous solution and methanol as mobile phase components. The obtained coffee and adulterants extract HPLC-UV-FLD fingerprints were evaluated by partial least squares regression-discriminants analysis (PLS-DA) resulting to be excellent chemical descriptors for sample discrimination. One hundred percent classification rates for both PLS-DA calibration and prediction models were obtained. In addition, Arabica and Robusta coffee samples were adulterated with chicory, barley, and flours, and the obtained HPLC-UV-FLD fingerprints subjected to partial least squares (PLS) regression, demonstrating the feasibility of the proposed methodologies to assess coffee authenticity and to quantify adulteration levels (down to 15%), showing both calibration and prediction errors below 1.3% and 2.4%, respectively.

Accelerated solvent extraction (ASE) and solid‐phase extraction (SPE) conditions were optimized by a high‐performance liquid chromatography‐fluorescence detector (HPLC‐FLD) method for the detection of piperazine in chicken tissues and pork. Piperazine residues were determined by precolumn derivatization with trimethylamine and dansyl chloride. Samples were extracted with 2% formic acid in acetonitrile using an ASE apparatus and purified using a Strata‐X‐C SPE column. The monosubstituted product of the reaction of piperazine with dansyl chloride was 1‐dansyl piperazine (1‐DNS‐piperazine). Chromatographic separations were performed on an Athena C18 column (250 × 4.6 mm, id: 5 μm) with gradient elution using ultrapure water and acetonitrile (5:95, V/V) as the mobile phase. The calibration curves showed good linearity over a concentration range of LOQ‐200.0 μg/kg with a coefficient of determination (R2) ≥ .9992. The recoveries and relative standard deviations (RSD values) ranged from 78.49% to 97.56% and 1.19% to 5.32%, respectively, across the limit of quantification (LOQ) and 0.5, 1, and 2.0 times the maximum residue limit (MRL; μg/kg). The limits of detection (LODs) and LOQs were 0.96 to 1.85 μg/kg and 3.20 to 5.50 μg/kg, respectively. The method was successfully applied for the validation of animal products in the laboratory. [ABSTRACT FROM AUTHOR]

• The CAA of different honeys were evaluated comprehensively. • The CAA markers in honey were firstly explored based on the QCAR. • The antioxidant research on fennel honey was firstly investigated. • Phenolic acids, flavonoids and free amino acids in different honeys were analyzed. • Isosakuranetin, cryptochlorogenic acid and methionine were firstly found in honey. Antioxidant molecules in honey contributed to various biological effects, but antioxidant components markers in honey are required to be investigated further. Phenolic compounds, flavonoids and free amino acids were analyzed using UPLC-MS/MS and HPLC-FLD from 39 honey samples, in which fennel honey was firstly investigated. Based on the quantitative composition-activity relationship, the cellular antioxidant activity (CAA) assay of various honeys is closely related with the interaction of some phenolic compounds (isoferulic acid, 3,4-dihydroxy benzoic acid, 4-hydroxy benzoic acid, chlorogenic acid, caffeic acid, gallic acid, cryptochlorogenic acid, p -coumaric acid, salicylic acid), flavonoids (isosakuranetin, sakuranetin, pinocembrin, vitexin, taxifolin, galangin, luteolin, chrysin) and free amino acids (Tyr, Gly, Ile, Glu, Val, Phe, Leu, Asp, His, Pro, Ala). The results would be beneficial for the understanding of the nutritional values, exploitation and utilization of honeys with different floral origins, further contributable to the market development and consumption choice of honey. [ABSTRACT FROM AUTHOR]

The maintenance of the cold chain is essential to ensure foodstuff conformity and safety. However, gaps in the cold chain may be expected so designing analytical methods capable to detect cold chain breaks is a worthwhile issue. In this paper, the possibility of using the amount of nine biogenic amines (BAs) determined in Thunnus albacares by HPLC-FLD for detecting cold chain breaks is approached. Tuna is stored at 3 different temperature conditions for 8 storage periods. The evolution of the content of BAs is analyzed through parallel factor analysis (PARAFAC), in such a way that storage temperature, BAs and storage time profiles are estimated. PARAFAC has made it possible to observe two spoilage routes with different relative evolution of BAs. In addition, it has enabled to estimate the storage time, by considering the three storage temperatures, with errors of 0.5 and 1.0 days in fitting and in prediction, respectively. Furthermore, a class-modelling technique based on partial least squares is sequentially applied to decide, from the amount of BAs, if there has been a cold chain break. Firstly, samples stored at 25 °C are statistically discriminated from those kept at 4 °C and −18 °C; next, frozen samples are distinguished from those refrigerated. In the first case, the probabilities of false non-compliance and false compliance are almost zero, whereas in the second one, both probabilities are 10%. Globally, the results of this work have pointed out the feasibility of using the amount of BAs together with PLS-CM to decide if the cold chain has been maintained or not. Image 1 • PCA and PARAFAC show a complex BA evolution over time at diverse storage temperatures. • Two different spoilage routes with different relative evolution of BAs are observed. • Estimating the storage time with errors of 0.5 (in fitting) and 1 day (in prediction). • Two PLS-CM sequentially applied allow for decision making about cold chain breaks. • Tuna stored at 25 °C, 4 °C and −18 °C, for different storage periods, is differentiated. [ABSTRACT FROM AUTHOR]

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We examined the optimum extraction solvent and conditions for fluorescence derivatization for a simultaneous analytical method that uses HPLC-FLD to measure five aflatoxins (AFB1, AFB2, AFG1, AFG2, and AFM1) in egg and processed egg samples. An egg sample and a processed egg sample were extracted under weakly acidic conditions using 0.1% formic acid in acetonitrile / water (9:1), cleaned up with an immunoaffinity column, and derivatized to fluoresce using trifluoroacetic acid (TFA) and n-hexane under warming conditions. The method was validated by replicate analysis of egg samples and granulated whole egg powder samples spiked with each AFB1, AFB2, AFG1, AFG2, and AFM1 at 0.1, 0.5 and 5.0 μg/kg. The recoveries of the egg samples and the granulated whole egg powder samples were 85.1-93.2% and 82.7-88.9%, respectively. The relative standard deviation (RSD) of repeatability and intermediate precision were ≤ 5.7% and ≤ 7.8%, respectively, all samples. The method detection limit (MDL) and the method quantification limit (MQL) were 0.004-0.010 μg/kg and 0.014-0.035 μg/kg, respectively, and MQL of the proposed method was lower than LOQ of official method in Japan. The proposed method was applied to four commercial egg samples and 19 processed egg samples, and no AFs were detected. [ABSTRACT FROM AUTHOR]

Aflatoxins (AFs) are type of mycotoxins produced by certain Aspergillus species. In the livers of cows, the aflatoxin В1 (AFB1) ingested with contaminated food is metabolized in carcinogenic aflatoxin М1 (AFM1) which is then excreted in the milk and poses a serious risk to the health of the consumers. In January of 2019, twenty five (25) samples of milk were collected from local farms in the surrounding area of Kumanovo, Republic of North Macedonia. The samples were analysed in the Centre for Public Health, Kumanovo. A method MKC EN ISO 14501:2007 for analysis of AFM1 by HPLC with fluorescence detection was applied. This method is selective, precise and applicative. The final analytical result has shown AFM1 below the LOD in any of the analyzed samples. Due to the well-known fact that AFM1 is toxic, i.e. carcinogenic and the fact that milk is widely used as staple food, continuous development as well as introduction of new, more sensitive methods for detection of AFM1 are required. [ABSTRACT FROM AUTHOR]

A total of 172 different salamis were purchased from farms and small salami factories located in four Italian regions (Piedmont, Veneto, Calabria, and Sicily) and analyzed for the presence of ochratoxin A (OTA). Analysis was performed by high-performance liquid chromatography coupled to a fluorimetric detector (HPLC-FLD). The detection limit (LOD) for the method used was 0.05 μg/kg, while the quantitation limit (LOQ) was 0.20 μg/kg; the average recovery rate was 89.1%. OTA was detected in 22 salamis, and 3 samples exceeded the Italian guidance value for OTA in pork meat (1 μg/kg). In particular, what emerges from this research is the high percentage of spicy salamis among positive samples (68.2%, 15 out of 22), although spicy salamis are only 27.3% of the total number of samples collected and analyzed. Red chili pepper contaminated by OTA could be responsible for the presence of the mycotoxin in these spicy salamis. It follow that, also the control of some ingredients used in the manufacture of these meat products, like spices, should not be neglected. [ABSTRACT FROM AUTHOR]

Abstract This presented study describes a method based on high performance liquid chromatography combined with fluorescence detection (HPLC-FLD) using N-(2-iodoacetyl)-1-pyrenemethylamine (NIPA) as a novel fluorescence labeling reagent for the determination of thyreostats in bovine milk. Five thyreostats, belonging to the group of imidazole and thiouracil, were investigated in this work: tapazole (TAP), thiouracil (TU), methylthiouracil (MTU), propylthiouracil (PTU) and phenylthiouracial (PhTU). Thyreostats were specifically purified by a silver ion solid phase extraction (Ag-SPE) cartridge and then labeled using NIPA. The labeled derivatives showed excellent fluorescence property with maximum excitation and emission wavelengths of 330 nm and 375 nm, respectively. The labeled derivatives were separated on a reversed-phase Eclipse SB-C18 column within 12 min. Excellent linearity (R2 > 0.995) of all thyreostats was achieved with the limits of detection (LODs) and the limits of quantitation (LOQs) in the low micrograms per liter range of 0.21–0.30 μg/L and 0.70–1.00 μg/L, respectively. Satisfactory recoveries in the range of 93.5–98.0% were obtained for all thyreostats. The developed method has been successfully applied to analyze thyreostats in bovine milk with good applicability. Thirty bovine milk samples have been investigated, and varying levels of thiouracil were detected in thirteen of these samples. The highest level in the raw milk reached a value of 4.5 μg/L. To our best knowledge, this study is the first to report the presence of naturally occurring thiouracil in milk by HPLC-FLD analysis. Highlights • A pre-column derivatization HPLC-FLD method was developed for the determination of thyreostats in milk samples. • LOD was in the low micrograms per liter range of 0.21–0.30 μg·L−1. • The proposed method was successfully applied to the determination of thyreostats in milk sample. • This study is the first to report the presence of naturally occurring thiouracil in milk by HPLC-FLD analysis. [ABSTRACT FROM AUTHOR]

Abstract The goal of the presented work is to develop a simple and sensitive high-performance liquid chromatography in combination with fluorescence detection (HPLC-FLD) method for the determination of four nitrofurans (NFs) metabolites compounds (semicarbazide (SEM), 1-aminohydantoin (AH), 3-amino-2-oxazolidinone (AOZ) and 3-amino-morpholinomethyl-2-oxazolidinone (AMOZ)) in foodstuffs. For this goal, we synthesized a novel fluorescence labeling reagent, 4-(carbazole-9-yl)-benzyl chloroformate (CBBC) to label NFs metabolites compounds. NFs metabolites compounds can be labeled rapidly only within 5 min at the room temperature (25 °C). The labeled derivatives showed excellent fluorescence property with maximum excitation and emission wavelengths of 375 nm and 410 nm, respectively. The labeled derivatives were analyzed on a reversed-phase Eclipse XDB-C18 column within 10 min. Excellent linearity (R2 > 0.995) of all NFs metabolites compounds was achieved with the limits of detection (LODs) and the limits of quantitations (LOQs) in the low micrograms per kilogram range of 0.20–0.30 μg·kg−1 and 0.70–1.00 μg·kg−1, respectively. Satisfactory recoveries in the range of 92.5–98.0% were obtained for all NFs metabolites compounds. Using the proposed HPLC-FLD method, we successfully determined four NFs metabolites compounds in different foodstuffs. As promising, this highly sensitive and reliable method would also be extended for the quantitation of NFs metabolites compounds in other samples. Graphical abstract Unlabelled Image Highlights • A novel fluorescence labeling reagent CBBC was synthesized to label nitrofurans (NFs) metabolites compounds. • A pre-column derivatization HPLC-FLD method was developed for the determination of NFs metabolites compounds in foodstuffs. • LODs were in the low micrograms per kilogram range of 0.2-0.3 μg·kg-1. [ABSTRACT FROM AUTHOR]

[Objectives] This study was conducted to determine capsaicin and dihydrocapsaicin in capsicum products. [Methods] The sample was ultrasonically extracted with anhydrous ethanol as the extraction solvent for capsaicin and dihydrocapsaicin, followed by centrifugation. The extract was subjected to HPLC separation with methanol-water (65:35) as the mobile phase, and a fluorescence detector (Ex = 229 nm, Em = 320 nm) was used to detect capsaicinoids in the sample. [Results] Capsaicin and dihydrocapsaicin had a good linear relationship in the range of 1-200 mg/L (R1² = 0.999 8, R2² = 0.999 6). The detection limits were both 0.007 mg/kg; the quantification limits were both 0.02 mg/kg; the precision was 0.235% and 0.754%, respectively; and the average recoveries were 95.94% and 95.39%, respectively. [Conclusions] The method is simple, rapid, with good sensitivity and precision, and is suitable for detecting capsaicin substances in capsicum products. [ABSTRACT FROM AUTHOR]

Abstract Aflatoxins (AFS) are toxic and carcinogenic fungal metabolites. Aflatoxin B1 is the most toxic and has been classified as a Group I carcinogen by the International Agency for Research on Cancer (IARC). Samples of imported rice were analyzed for their AFS content. Finley ground rice subsamples were extracted with water/methanol (100:150 v/v) followed by purification with Immunoaffinity columns (IAC). AFS purified from extracts were determined with RP-HPLC-FLD using post column electrochemical derivatization with a Kobra Cell. Concentrations of aflatoxin B1 and total AFS in test rice samples were ≤0.123 and ≤2.58 µg/kg, respectively. Tween 80 improved recoveries (86 and 106%) of aflatoxin B1 and aflatoxin G1 from brown rice. Recoveries of Aflatoxin B2 and aflatoxin G2 were substantially reduced (non-detected to 27%) by Tween 80 used in IAC cleanup of brown rice extracts. Visible dense growth of Aspergillus parasiticus (food isolate) occurred at 25 °C but higher aflatoxin B1amounts (23.9–39.3 µg/kg) accumulated when the mold grew at 37 °C in rice seeds stored for three weeks. It could be concluded that levels of aflatoxin B1 and total AFS in rice samples were within the permissible amounts of the EU and other international legislations. [ABSTRACT FROM AUTHOR]

Samples (n = 485) of raw (n = 394) or heat-treated (n = 91) milk of three different species (cow, n = 170; sheep, n = 133; donkey, n = 84), collected 2013-2016 in Western Sicily (Southern Italy), were analyzed for aflatoxin M1 (AFM1) by enzyme-linked immunosorbent assay (ELISA). Positive ELISA results were further analyzed by HPLC with fluorescence detection. Both methods had a detection limit for AFM1 in milk of 7 ng kg−1. ELISA yielded 12.9 and 5% positives in cows and sheep milk, respectively, all samples of donkey milk were negative. Levels of AFM1 were in most cases at 0.007-< 0.05 μg kg−1, only two samples (sheep milk) slightly exceeded the European Union maximum level of 0.05 μg kg−1. Only 6% of the samples were positive for AFM1 in a concentration range of 0.008-0.15 μg kg−1. Only milk samples collected directly from farms were positive. Overall, the levels were much lower than previously reported for Southern Italy cow and sheep milk samples purchased in retail stores. The results of this work indicate a continuous improvement of the feeding techniques on dairy farms of Southern Italy, which is essential to ensure consumers' protection. [ABSTRACT FROM AUTHOR]

Abstract Paralytic shellfish toxins (PST) and tetrodotoxin (TTX) are naturally-occurring toxins that may contaminate the food chain, inducing similar neurological symptoms in humans. They are co-extracted under the same conditions and thus their combined detection is desirable. Whilst PST are regulated and officially monitored in Europe, more data on TTX occurrence in bivalves and gastropods are needed before meaningful regulations can be established. In this study, we used three separate analytical methods - pre-column oxidation with liquid chromatography and fluorescence detection, ultrahigh performance hydrophilic interaction liquid chromatography (HILIC) tandem mass spectrometry (MS/MS) and HILIC high resolution (HR) MS/MS - to investigate the presence of PST and TTX in seawater and shellfish (mussels, clams) collected in spring summer 2015 to 2017 in the Mediterranean Sea. Samples were collected at 10 sites in the Syracuse Bay (Sicily, Italy) in concomitance with a mixed bloom of Alexandrium minutum and A. pacificum. A very high PST contamination in mussels emerged, unprecedentedly found in Italy, with maximum total concentration of 10851 μg saxitoxin equivalents per kg of shellfish tissue measured in 2016. In addition, for the first time TTX was detected in Italy in most of the analysed samples in the range 0.8–6.4 μg TTX eq/kg. The recurring blooms of PST-producing species over the 3-year period, the high PST levels and the first finding of TTX in mussels from the Syracuse bay, suggest that monitoring programmes of PST and TTX in seafood should be activated in this geographical area. Highlights • Recurring blooms of Alexandrium minutum and Alexandrium pacificum in Syracuse bay. • Toxin profile and content of seawater and shellfish collected in 2015, 2016, 2017. • Paralytic shellfish toxins contaminating mussels at levels up to 10851 μg STX eq/Kg. • First finding in Italy of tetrodotoxin in mussels at levels up to 6.4 μg TTX eq/Kg. • Comparison among PreCOX-HPLC-FLD, UHPLC-HILIC-MS/MS, and HPLC-HILIC-HRMS for PST. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are a group of more than 100 different chemical substances, which contain two, or more fused aromatic rings most of them toxic or carcinogenic. In this study, the Quechers extraction conditions were adapted to perform the extraction of aqueous samples. Quechers has become a standard technique for the analysis of pesticides and other organic substances. Its simplicity and low cost have made it popular in laboratories around the world for processing samples such as fruits and vegetables. The success of this method on solid samples contrasts with the advances in the extraction of aqueous samples where tedious steps of extraction, concentration and solvent changes must be carried out prior to the instrumental analysis. A methodology for the liquid-liquid extraction (water/acetonitrile) of 15 PAHs in aqueous matrices was developed. The mixture was saturated with anhydrous sodium sulfate to cause the partitioning and the extract was analyzed by High-Resolution Liquid Chromatography with Fluorescence Detection (HPLCFLD). The recoveries of analytes achieved (61-114%) were comparable to those expected using traditional extraction techniques, and with moderate uncertainty. The results were consistent with the expectations for of the required analytical and concentration ranges. [ABSTRACT FROM AUTHOR]

The prevalence of aflatoxins (AFs) B1, B2, G1, and G2 in Iranian edible oils were assessed by immunoaffinity column cleanup and HPLC equipped with a fluorescence detector (HPLC-FLD). Ninety-seven samples including sunflower, canola, refined olive, unrefined olive, frying, and blend oils were collected from eight provinces (n = 15 samples of refined olive oil, n = 15 samples of unrefined olive oil, n = 15 samples of sunflower oil, n = 15 samples of canola oil, n = 17 samples of frying oil, and n = 20 samples of blend oil). Also, cancer risk of aflatoxins in the adults and children due to ingestion of edible oils was estimated via margin of exposure (MOE) estimation in the Monte Carlo simulation (MCS) model. Considering the limit of detection (LOD) of the current study, two unrefined olive oil samples from Zanjan Province were contaminated with AFB2 in the concentrations of 0.2 and 0.4 ng/g while other samples were free from AFB1, AFB2, AFG1, and AFG2. This study revealed that about 98% of the collected samples were free from AFs and the concentrations of AFs in the polluted samples were within the standard range suggested by European Commission regulation (20 μg/kg). However, health risk assessment indicated that both adult and children in the Zanjan Province are at considerable liver cancer risk (percentile 95% of MOE < 10,000 value). Therefore, national plan to address this issue and strict inspection of edible oil products by the regulatory bodies are suggested. [ABSTRACT FROM AUTHOR]

A fast and simple method for analysis of 14 PAHs in grilled and smoked muscle foods using acetonitrile based-extraction was validated. The optimum amounts of magnesium sulfate and sodium chloride that promoted phase separation of acetonitrile extract containing PAHs from water phase were selected by Central Composite Design. Matrix-matched calibration curves were constructed by adding different concentrations of PAHs and then subjected to extraction followed by HPLC with fluorescent detection. An excellent linearity for all compounds applying weighed least squares linear regression procedure was achieved. LODs and LOQs were lower than 0.12 and 0.39 ng g−1 respectively. Validation was done according to International Conference on Harmonization recommendations for 14 PAHs. The criteria for 4 EU marker PAHs (benz[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene) established by European Comission Regulation No. 836/2011 was also accomplished. Repeatability and reproducibility were lower than 8 and 13.3%, and the most of recoveries fall in the range of 80-110% in different grilled and smoked muscle foods. The proposed method is a robust tool for determination of PAHs in grilled and smoked muscle foods, being easy to perform in short time. [ABSTRACT FROM AUTHOR]

Urinary aromatic diamines are exposure biomarkers of diisocyanate which are highly irritating to skin, mucosa and the upper respiratory system. In this study, a highly sensitive and selective high-performance liquid chromatography-fluorescence detection (HPLC-FLD) method was developed for determination of three aromatic diamines, 4,4′-methylenedianiline (MDA), 2,4-toluenediamine (4TDA) and 2,6-toluenediamine (6TDA) exposed to corresponding diisocyantes in human urine. The whole idea is based on an intramolecular excimer-forming fluorescence derivatization using 4-(1-pyrene)butanoyl chloride (PBC), followed by performing HPLC-FLD analysis.The resulting polypyrene-labeled derivatives of these aromatic diamines provided intramolecular excimer fluorescence at the emission wavelength of 475 nm wavelengths, which was shifted markedly to the higher emission wavelengths as compared with the wavelengths of the pyrene monomer. Under this condition, interferences such as amino acids and biogenic monoamines gave no peaks. It was found that using PBC derivatization, it was possible to improve the sensitivity and selectivity toward aromatic diamines. The limits of detection (LODs) were in the range of 0.30–0.52 ng/L, while the limits of quantitation (LOQs) between 1.05 and 1.63 ng/L. The intraday and interday precision was in the range of 3.6–4.5% and 4.1–5.7%, respectively. The proposed method was successfully applied to the quantitation of these exposure biomarkers in human urine samples. [ABSTRACT FROM AUTHOR]

A simple, fast and ecological analytical method using a semi-automatic fat extractor and HPLC-FLD (fluorescence detection) for determination of polycyclic aromatic hydrocarbon markers i.e. benzo(a)anthracene (BaA), chrysene (Chr), benzo(a)pyrene (BaP) and benzo(b)fluoranthene (BbF) in cocoa butter has been validated. Validation’s procedure performed out in concordance with French standard NF V03-110 (2010) was based on existing polycyclic aromatic hydrocarbon (PAH) determination methods in various smoked foodstuffs and edible vegetable oils. Determination of correlation coefficients for specific PAHs ranged from 0.9992 to 0.9998. Respective values of limits of detection were 0.010, 0.011, 0.033 and 0.029 μg kg−1 and those of quantification were 0.035, 0.038, 0.111 and 0.098 μg kg−1 for BaA, Chr, BbF and BaP. Both values of repeatability and intermediary precision tests coefficients of variation were less than 5%. Recovery scores of four PAH markers matched EU standard 836/2011 recommendations. Sum of four PAH markers (BaA, Chr, BbF, BaP) contents varied from 5.42 ± 0.58 to 11.37 ± 0.01 μg kg−1 whereas those of BaP was comprised between 0.26 ± 0.00 and 1.75 ± 0.13 μg kg−1 in 20 cocoa butter samples extracted from raw cocoa bean stored at Ivorian cocoa farmer levels. [ABSTRACT FROM AUTHOR]

Aflatoxin M1 (AFM1) is a well-known mycotoxin that can be found in the milk of animals that have ingested feed contaminated with aflatoxin B1 (AFB1). In Italy, the development of donkey farms is mainly due to growing request of donkey milk, which is considered an incomparable substitute for human mother’s milk for its chemical composition and organoleptic characteristics. The aim of this study was to assess the occurrence of AFM1 in donkey milk produced in a farm in Northern Italy, also in view of the few data available about the presence of this mycotoxin in this type of milk. Therefore, 63 milk samples were collected and analyzed using a fast and sensitive HPLC and fluorescence detection (FLD) method previously optimized and validated. None of the milk samples collected were found to be contaminated at a level above the limit of quantification (LOQ) (0.0125 ng/mL), while only one sample showed traces of the mycotoxin at a concentration between the limit of detection (LOD) and LOQ (0.0044 ng/mL), well below the legal limit established for infant milk and follow-on milk (0.025 ng/mL). These results are in line with those of the few similar surveys carried out on donkey milk and seem to indicate a low risk of AFM1 contamination for this food.

[Display omitted] • Cotton fiber was used as the normal-phase adsorbent for zearalenone extraction. • Extraction was conducted by applying pull–push operations to the syringe plunger. • Extraction zearalenone from cereal crops/traditional Chinese medicines was effective. • The extraction method was simple, low-cost, and labor/time-saving. • Coupled with LC-MS/MS, quantitative analysis of zearalenone in corn was validated. Here, an in-syringe cotton fiber solid-phase extraction (CF-SPE) method for the effective pretreatment of zearalenone (ZEA) in cereal crops and traditional Chinese medicines was developed. In this method, a syringe tube is packed with degreasing cotton, which serves as the normal-phase adsorbent for extracting ZEA from the nonpolar solvent extract of samples. The entire extraction process, including activation, sampling, washing, and elution steps, can be conveniently performed by employing a series of pull–push operations to force the solution to pass through the degreasing cotton. Optimal extraction recoveries were achieved using 200 mg of degreasing cotton as the adsorbent, a 3 mL volume of sampling solution, a desorption solution consisting of 2 mL of acetonitrile, and 4 pull–push times for both sampling and desorption. Coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS), quantification of ZEA in corns was achieved by validating matrix-matched calibration curves in the range of 0.1–100.0 ng/g with satisfactory linearity (R2 = 0.9996). The limit of detection (LOD) was calculated to be 0.025 ng/g with a signal-to-noise ratio (S/N) of 3. The intra-/inter-day relative recoveries and relative standard deviations were calculated to be in the ranges of 93.8%–110.4% and 3.2%–9.3%, respectively, which were satisfactory for quantitative analysis. The proposed in-syringe CF-SPE-LC-MS/MS method is simple, cheap, and labor/time-saving. [ABSTRACT FROM AUTHOR]

Determination of aflatoxins as a group of potent contaminations in many food products is a common analysis in food quality control laboratories. For quantification of the four most toxic aflatoxins (AFs) (i,e. AF B1, B2, G1, and G2) in food and feed, a standard method involving a liquid extraction step followed by immunoaffinity purification and high-performance liquid chromatography (HPLC) is often used. In this work, this method is verified based on the requirements of ISO/IEC 17025 for the determination of aflatoxins in peanut kernel samples. All the method figures of merit including calibration, evaluation of limit of determinations (LODs) and limit of quantifications (LOQs), accuracy, precision, and uncertainty of the method are explained in detail. The accuracy of the applied method was verified by analysis of a CRM and calculation of the recovery. The relative standard deviations of the method (n = 6) were in the range of 4.99–7.85%. The LODs and LOQs of the method were found to be 0.15 and 0.50 μg. kg−1 for AFB1 and G1 and 0.06 and 0.2 μg kg−1 for AFB2 and G2, respectively. Finally, the uncertainties in the determination of aflatoxins concentrations, at the maximum permissible levels were calculated using the GUM procedure as 0.42, 0.094, 0.42, and 0.083 μg. kg−1 for AFB1, B2, G1, and G2, respectively. • Aflatoxins were quantified in peanuts by immunoaffinity column cleanup and HPLC-FLD. • Method verification was carried out based on ISO/IEC 17025 requirements. • Figure of merits of the method were calculated. • Uncertainties of the obtained results were calculated at maximum permissible level. [ABSTRACT FROM AUTHOR]

Presence of aflatoxin M1 (AFM1) in milk should be continuously controlled in order to protect the population from risks associated with its proven toxicity and carcinogenicity. During recent years, there has been an increase in demand for development of sensitive, accurate, simple and fast method which is reliable to detect AFM1 at low concentrations found in milk samples. For that purpose, enzyme linked immunosorbent asssay (ELISA), high performance liquid chromatography with fluorescence detector (HPLC-FLD) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) were optimized and validated in order to apply them for AFM1 analysis in naturally contaminated milk samples (n=15), and to assess the closeness of agreement between results of three different methods. The obtained validation parameters indicate that all three methods are suitable for determination of AFM1 in milk samples. The statistical analysis of variance between methods and obtained correlation coefficients indicate that strong correlation exists between methods. All three methods are satisfactory in meeting the requirements for official control purposes.

A magnetic solid phase extraction technique followed by liquid chromatography with a fluorescence detector for naproxen analysis in human urine samples was developed. The method includes the extraction of naproxen with a magnetic solid synthetized with magnetite and poly 4-vinylpriridine, followed by the magnetic separation of the solid phase and desorption of the analyte with methanol. Under optimal conditions, the linear range of the calibration curve was 0.05–0.60 μg L−1, with a limit of detection of 0.02 μg L−1. In all cases values of repeatability were lower than 5.0% with recoveries of 99.4 ± 1.3%. Precision and accuracy values are adequate for naproxen (Npx) analysis in urine samples.

The introduction of antimicrobial residues in the food chain has a significant impact on human health. An innovative solution to avoid their presence in meat is the adaptation of current control methods for use with in vivo matrixes. Thus, the aim was to obtain paired blood and muscle samples from pigs treated with some of the main antimicrobials currently used in veterinary medicine (oxytetracycline, sulfamethoxypyridazine, enrofloxacin, amoxicillin), and to compare their rate of depletion in both matrixes. Antimicrobial concentrations in paired samples of blood and muscle were determined by liquid chromatography with tandem mass spectrometry (LC–MS/MS) or high performance liquid chromatography with fluorescence detection (HPLC-FLD). A comparison between values obtained in muscle and blood showed a similar distribution in both matrixes for oxytetracycline; for sulfamethoxypyridazine, a similar decrease rate but a concentration three times higher in blood compared to muscle was found; for enrofloxacin, we found significant differences in the rate of depletion, with similar antimicrobial concentrations in both matrixes with values close to the maximum residue limit (MRL) and higher amounts in muscle for values that lay considerably over the MRL. Conversely, amoxicillin depletion was so rapid that its appearance in carcasses does not seem to pose a risk. Therefore, blood would be a feasible matrix for the development of new in vivo tests.

Ochratoxin A (OTA) is a mycotoxin that may be present in various food and feed of plant and animal origin, including chicken meat. In Italy, backyard poultry farming is rather widespread. Animals are raised for meat, eggs and for ornamental purpose, and they are often fed with home-made diets not subject to official controls. The purpose of this study was to evaluate exposure of ornamental and backyard chickens to OTA using biliary ochratoxin A as a biomarker. Therefore, bile samples, in addition to kidney, liver and muscle, were collected from 102 chickens reared in 16 farms located in 6 Italian regions. High-performance liquid chromatography method and fluorimetric detection (HPLC-FLD) analysis were carried out firstly on bile from all animals, and OTA was detected in 12 chickens (concentration range 3.83−170.42 µg/L). Subsequently, the kidneys of these chickens were also analysed, and the mycotoxin was not detected. The analytical detection limits (LODs) of OTA in bile and kidney were 2.1 µg/L and 0.1 µg/kg, respectively. In conclusion, these animals were exposed to OTA but their meat can be considered safe, given that this mycotoxin, if present, concentrates highest in kidneys. Biliary ochratoxin A confirms its use as a valid biomarker to assess exposure of poultry to OTA.

Locust is esteemed as a traditional Chinese medicine, as well as one of the most important nutritional foods especially in Asian countries. However, some toxic secondary metabolites such as mycotoxins are usually found in different parts of locust to affect its quality and safety. This study aimed to investigate the aflatoxins (AFs) contaminated parts by observing Aspergillus flavus, spores’ diameter, amount and distribution on head, tentacle, wing, belly and shank parts of the locust with scanning electron microscopy (SEM). Furthermore, to assess the residue levels of multi-mycotoxins in the locust, the high performance liquid chromatography with fluorescence detection (HPLC-FLD) was adopted. The technique was used to determine the contents of AFs, zearalenone (ZON) and α-zearalenol (α-ZOL) in locust and the positive samples were confirmed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The chromatographic conditions, MS/MS parameters and the method of sample extraction were carefully optimized. Results revealed that obvious differences of Aspergillus flavus strains and spores were found, while the spores’ diameter ranged from 3.0 to 13.0 μm in different contaminated parts of the locust samples. The HPLC-FLD method for multi-mycotoxins analysis showed good selectivity, linearity, recovery and precision. Limits of quantification (LOQs) were lower than 27.6 μg/kg, while limits of detection (LODs) were in the range of 0.02–8.6 μg/kg. The accuracy of the developed method was validated regarding recoveries of 80.1–118.1% with relative standard deviation (RSD) ≤ 11.4%. Finally, the developed multi-mycotoxin method was applied for screening of these mycotoxins in 11 commercial locust samples. Only AFB1 and AFB2 were found in six samples, and the contamination levels ranged from 0.12 to 4.4 μg/kg, which were lower than the maximum residue limit and can be used safely. This is the first report on the exploration of contamination parts and levels of multi-mycotoxins in medicinal and edible locust. The combined method of SEM and HPLC-FLD exhibited advantages of low cost, high sensitivity, rapid determination, convenience and especially intuitive judgment, which is proposed for contamination parts observation, for the large-scale quantification of multi-mycotoxins in other medicinal animal matrices.

The high acidity and complex components of Hibiscus sabdariffa have provided major challenges for sensitive determination of trace aflatoxins. In this study, sample pretreatment of H. sabdariffa was systematically developed for sensitive high performance liquid chromatography-fluorescence detection (HPLC-FLD) after ultrasonication-assisted extraction, immunoaffinity column (IAC) clean-up and on-line post-column photochemical derivatization (PCD). Aflatoxins B1, B2, G1, G2 were extracted from samples by using methanol/water (70:30, v/v) with the addition of NaCl. The solutions were diluted 1:8 with 0.1 M phosphate buffer (pH 8.0) to negate the issues of high acidity and matrix interferences. The established method was validated with satisfactory linearity (R > 0.999), sensitivity (limits of detection (LODs) and limits of quantitation (LOQs) of 0.15–0.65 and 0.53–2.18 μg/kg, respectively), precision (RSD

An easy and quick sample pretreatment method, air-assisted dispersive liquid-liquid microextraction (AA-DLLME), has been introduced for the isolation and enrichment of aflatoxins B1, B2, G1, and G2 from rice samples prior to HPLC-FLD analysis. The method has also been compared with immunoaffinity column clean-up (IAC) method. In the case of AA-DLLME, the dispersion of extractant is formed in the absence of a disperser solvent and with the help of air bubbles. Several crucial factors, including the volume and type of extraction solvent, the volume of aqueous phase, and the number of extraction cycles were studied to obtain the optimal conditions. Under the optimal conditions, the suggested technique showed linearity in the range of 0.08-10 ng/mL with low limits of detection (0.68, 0.68, 0.13, and 0.13 ng/g for aflatoxins B1, G1, B2, and G2, respectively) and good sensitivity with limits of quantification of 2.0, 2.0, 0.4, and 0.4 ng/g for aflatoxins B1, G1, B2, and G2, respectively. The proposed procedure was successfully used to evaluate aflatoxins (AFs) in rice samples and acceptable recoveries in the range of 76.0-109.3% with appropriate precision (RSD < 14.2%) were obtained. [ABSTRACT FROM AUTHOR]

Oxidized white wines are produced by techniques that provide a barrel ageing which can range from a few years to some decades. This step, characterized by the metabolic activity of peculiar strains of Saccharomyces cerevisiae yeast, can affect the chemical composition of these wines and the production of unwanted substances such as biogenic amines. In this study, Vernaccia di Oristano wines from different vintages have been analysed for the first time regarding the content of biogenic amines and amino acids (by HPLC-FLD), and polar compounds (by HPLC-DAD and LC-MS). Furthermore, colour and technological parameters (contents of alcohol, reducing sugars, total and volatile acidities, pH and organic acids) of the wines were also evaluated. Older samples showed dark shades, which may have derived from polyphenols' oxidation while ageing. Some typical ageing products, such as 5-(hydroxymethyl)furfural and hydroxycinnamic acid derivatives were found in larger quantities in these samples, as well as the purinic compound xanthine, which was also detected in relevant concentrations. Additionally, as expected, the average of the main biogenic amines quantified in Vernaccia di Oristano was higher compared to non-oxidized white wines, especially in the older samples. Thus, though this content does not exceed values which spoil the quality of the wine, the monitoring of the winemaking conditions is suggested, to further limit the presence of these undesirable compounds. [ABSTRACT FROM AUTHOR]