Olive Oil as a Transport Medium for Bioactive Molecules of Plants?-An In Situ Study.

(1) Caries and erosions still remain a challenge for preventive dentistry. Certain plant extracts have shown beneficial effects in preventive dentistry. The aim of this study was to evaluate the antibacterial, anti-adherent and erosion-protective properties of ellagic acid (EA) as a polyphenolic agent. The combination with olive oil was investigated additionally to verify a possible improved bioactive effect of EA. (2) An in situ study was carried out with six subjects. Individual splints were prepared with bovine enamel specimens. The splints were worn for 1 min (pellicle formation time). Thereafter, 10 min rinses were performed with EA in water/in oil. Bacterial adherence was evaluated by fluorescence microscopy (DAPI, ConA, BacLight) after an 8 h oral exposition time. Additionally, the splints were worn for 30 min to quantify demineralization processes. The ultrastructure of the pellicle was investigated after an oral exposure time of 2 h under a transmission electron microscope. Statistical analysis was performed by Kruskal-Wallis tests, Mann-Whitney U tests and Bonferroni-Holm correction. (3) Rinsing with EA led to a significant reduction of adherent vital and dead bacteria. The combination with olive oil did not improve these outcomes. The assessment of glucan structures after rinsing with EA in water showed significant effects. Significant differences were observed for both rinses in calcium release at pH 3.0. After rinsing with EA in oil, significantly less calcium was released compared to rinsing with EA in water (pH = 3.0). (4) Olive oil is not suitable as a transport medium for lipophilic polyphenols. EA has anti-adherent and antibacterial properties in situ. EA also shows erosion-protective effects, which can be enhanced in combination with olive oil depending on the pH value. Ellagic acid has a neutral pH and could be an opportunity in the treatment of specific patient groups (xerostomia or mucositis).

Preventive Applications of Polyphenols in Dentistry-A Review.

Polyphenols are natural substances that have been shown to provide various health benefits. Antioxidant, anti-inflammatory, and anti-carcinogenic effects have been described. At the same time, they inhibit the actions of bacteria, viruses, and fungi. Thus, studies have also examined their effects within the oral cavity. This review provides an overview on the different polyphenols, and their structure and interactions with the tooth surface and the pellicle. In particular, the effects of various tea polyphenols on bioadhesion and erosion have been reviewed. The current research confirms that polyphenols can reduce the growth of cariogenic bacteria. Furthermore, they can decrease the adherence of bacteria to the tooth surface and improve the erosion-protective properties of the acquired enamel pellicle. Tea polyphenols, especially, have the potential to contribute to an oral health-related diet. However, in vitro studies have mainly been conducted. In situ studies and clinical studies need to be extended and supplemented in order to significantly contribute to additive prevention measures in caries prophylaxis.

Stability of pyrrolizidine alkaloids from Senecio vernalis in grass silage under different ensilage conditions.

BACKGROUND: This study evaluated the degradation of pyrrolizidine alkaloids (PAs) from eastern groundsel (Senecio vernalis) in grass silage prepared with different inoculants. Silages were produced from ryegrass with 230 g kg-1 dry matter (DM) content and mixed with eastern groundsel (9:1; w/w fresh matter basis) containing 5.5 g kg-1 DM PA. Treatments were: CON (untreated control), LP (3.0 × 105 cfu g-1 Lactobacillus plantarum DSMZ 8862/8866) or LBLC (7.3 × 104 cfu g-1 Lactobacillus buchneri LN40177 / Lactobacillus casei LC32909), and each of the treatments in combination with 30 g kg-1 molasses. Silages were prepared in glass jars and opened after 3, 10, and 90 days. Fermentation characteristics were determined and the PAs analyzed. RESULTS: Although the levels of fermentation acids differed between treatments, results indicated good quality of all silages during 90 days. Significant time (P < 0.001) and treatment (P < 0.001) effects were observed for PAs. Concentrations of senecionine and seneciphylline decreased with molasses, declined over time, and were negatively correlated with lactic, propionic, and butyric acid, or with lactic and butyric acid in case of seneciphylline. In all silages, seneciphylline and senecionine N-oxides were undetectable after 3 days, whereas senkirkine, the most abundant PA, remained stable. CONCLUSIONS: Silage prepared from grass contaminated with eastern groundsel still contained high PA levels, and was hence a potential health hazard. Molasses supplementation reduced concentrations of senecionine and seneciphylline, while the bacterial inoculants had no effect. Other potentially toxic PA metabolites were not analyzed in the present study and further research is needed. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Ultra turrax® tube drive for the extraction of pesticides from egg and milk samples.

The Ultra turrax® tube drive, already successfully applied for the extraction of plant materials, has also proved to be suitable for the analysis of pesticides in eggs and milk. In comparison to the matrix solid-phase dispersion (MSPD), the extraction is less time-consuming at excellent extraction efficiency. Further advantages are the flexibility of the extraction conditions with respect to the pH value and water activity. So, even strongly acidic pesticides such as phenoxy carboxylic acids can be extracted. Eighty-nine GC-amenable and 75 LC-amenable pesticides, which had been detected successfully in whole chicken eggs following MSPD extraction and further processing according to Hildmann et al., could also be analyzed with the modified method. In addition, the analysis spectrum could be expanded by 4 GC- and 37 LC-amenable substances. Of the 208 pesticides tested, 205 substances could be detected in whole chicken eggs. Similar excellent results were achieved for the milk matrix. Furthermore, the modified extraction method allows a determination of the fat content from the same analysis approach.

The Polyphenolic Composition of Cistus incanus Herbal Tea and Its Antibacterial and Anti-adherent Activity against Streptococcus mutans.

The Mediterranean plant Cistus incanus is rich in polyphenols and has shown several pharmacological activities, mainly antibacterial effects. Furthermore, in situ studies revealed that a C. incanus infusion reduces the initial bacterial adhesion in the oral cavity due to the polyphenols, an indication that C. incanus might reduce the risk of caries disease. In the present study, the polyphenols from four different commercial C. incanus herbal teas were extracted by standardized accelerated solvent extraction for in vitro tests and by an infusion for in situ tests. Both extracts were characterized qualitatively and quantitatively by high-performance liquid chromatography and only the polyphenol content differed slightly. By means of diode array detection and mass spectrometry, 29 polyphenols, including ellagitannins, flavanols, and glycosylated flavonols, were identified. Thereby, only quantitative but no qualitative differences between the four samples were detected. Furthermore, the in vitro antibacterial activity of the C. incanus accelerated solvent extracts against Streptococcus mutans, one of the primary cariogenic bacterial species, was examined using a live/dead assay (BacLight®). With this approach, C. incanus yielded antibacterial properties. Additional in situ experiments indicated that rinses with a C. incanus infusion reduced the initial bacterial colonization of enamel samples exposed to oral fluids for over eight hours. Furthermore, it was shown by transmission electron microscopy that the application of a C. incanus infusion modifies the ultrastructure of the acquired enamel pellicle, yielding a more electron-dense morphology. It can be assumed that the polyphenols are responsible for the observed effects.

Evaluation of matrix effects in different multipesticide residue analysis methods using liquid chromatography-tandem mass spectrometry, including an automated two-dimensional cleanup approach.

Pesticide residue analysis is an important part of food quality control. Three of the most widely used methods are the DFG S19 (extraction with acetone), the ChemElut method (extraction with methanol), and QuEChERS (quick, easy, cheap, effective, rugged, safe; acetonitrile-based). Despite many developments in the field of sample preparation, matrix effects are still one of the most disturbing problems in routine analysis. In this study, we compare the matrix effects in LC-MS analysis after using these three methods in pesticide analysis. Using postcolumn infusion, we were able to visualize all suppressions over the whole chromatogram in matrix-effect profiles. Recently, we also presented a system for the determination of up to 300 pesticides from various kinds of fruit and vegetables. For the measurement, we injected an aliquot of a raw acetonitrile extract. The subsequent cleanup was carried out fully automated by a multidimensional LC. Matrix compounds and analytes are separated in the first dimension on a hydrophilic interaction LC column. In this study, we also compared this new approach with the classical methods. The matrix-effect profiles showed less suppression with the hydrophilic interaction LC-based cleanup. A final evaluation of the partitioning steps of all methods confirmed the benefits of the chromatographic cleanup approach.

Application of the precolumn back-flush technology in pesticide residue analysis: a practical view.

Precolumn back-flushing is a matrix minimization technique in GC in which the carrier gas flow of the precolumn is reversed after the transfer of the highest boiling analyte to the analytical column. Practical details concerning this technology have rarely been published although it is widely used. This paper now focuses on the practical implementation of precolumn back-flushing for pesticide residue analysis of complex food matrices. Fitting the analytical column into the precolumn was found to be essential for comparable analyte responses with and without back-flushing. The effectiveness of the reverse column flow technique is mainly affected by the transfer time after which back-flushing starts. The transfer time was found to depend on which kind of injected matrix is used and the state of the precolumn. For the regular adaptation of the transfer time in routine analysis, a simple test was introduced in which 13-C-labeled deltamethrin and indeno[1,2,3-c,d]pyrene were added to the prepared extract. Chromatograms, LOQ and RSD of up to 99 pesticides in citrus oil and liver extracts proved a clearer identification and enhanced quantification using precolumn back-flushing compared to measurements without this technology. Furthermore, reduced system maintenance could be achieved through back-flushing.

Analysis of triazole-based metabolites in plant materials using differential mobility spectrometry to improve LC/MS/MS selectivity.

Triazole-derivative metabolites can occur in plant and animal materials and in water. Due to their physical-chemical properties, their analysis in complex matrixes is very difficult. The objective of this work was to develop a method for the analysis of these analytes that is easy to handle, quick, and enables quantification at a residue level of 0.01 mg/kg. Using the LC-differential mobility spectrometry/MS/MS system, cleanup and derivatization processes became unnecessary. For more than 10 representative plant materials it could be shown that the new method is valid and reproducible, thus leading to accurate and reliable results.

Simultaneous Mass Spectrometric Detection of Proteins of Ten Oilseed Species in Meat Products.

Food fraud is a common issue in the modern food industry. The undeclared use of foreign proteins in meat products is a major concern in this context. Oilseeds are ideal for this purpose due to their high protein content and since huge amounts of oil meal are obtained as a by-product of oil production. Therefore, a UHPLC-MS/MS method was developed for the simultaneous detection of chia, coconut, flaxseed, hemp, peanut, pumpkin, rapeseed, sesame, soy, and sunflower proteins in meat products. Potential tryptic peptide markers were identified by high-resolution mass spectrometry. The final twenty peptide markers selected, which are specific for one of the ten species targeted, were each measured by multiple reaction monitoring. To the best of our knowledge, twelve new heat-stable marker peptides for chia, coconut, flaxseed, pumpkin, rapeseed, sesame and sunflower have not been reported previously. Emulsion-type sausages with 0.01, 0.25, 0.50, 0.75 and 1.00% protein addition by each oilseed species were produced for matrix calibration. No false-positive results were recorded. In the quantification of the ten oilseed species, 466 of 480 measuring data points of the recovery rate in unknown sausages (0.15 and 0.85% protein addition by each oilseed species) were in the accepted range of 80-120%.

Barbecue conditions affect contents of oxygenated and non-oxygenated polycyclic aromatic hydrocarbons in meat and non-meat patties.

The contents of eight oxygenated polycyclic aromatic hydrocarbons (OPAHs; anthracene-9,10-dione, benzo[a]anthracene-7,12-dione, 11H-benzo[b]fluorene-11-one, 6H-benzo[cd]pyren-6-one, 7H-benzo[de]anthracene-7-one, 9,10-dihydro-8H-benzo[a]pyren-7-one, fluoren-9-one, and naphthacene-5,12-dione) and six PAHs (anthracene, fluorene, and PAH4) were investigated in barbecued meat and non-meat patties. The patties were prepared with ten setups (six replicates, each) of barbecue conditions defined by grill type, grate height, heating medium, and barbecue time. The highest median contents were observed with a disposable grill (OPAHs: 46.3 µg/kg; PAHs: 40.7 µg/kg) and a charcoal grill (OPAHs: 29.6 µg/kg; PAHs: 23.3 µg/kg). Fluoren-9-one and anthracene-9,10-dione were the dominant compounds within OPAHs, but also the four toxicologically most relevant OPAHs were detected with a total up to 11.8 µg/kg. Pairs of OPAHs and corresponding PAHs did not show strong correlations, as individual OPAHs and PAHs were affected differently by the barbecue conditions. No suitable markers for OPAH prediction could be found. We recommend to include OPAHs in future PAH investigations.

Cholesterol-raising diterpenes in types of coffee commonly consumed in Singapore, Indonesia and India and associations with blood lipids: a survey and cross sectional study.

BACKGROUND: To measure the content of cholesterol-raising diterpenes in coffee sold at the retailer level in Singapore, Indonesia and India and to determine the relationship of coffee consumption with lipid levels in a population-based study in Singapore. METHODS: Survey and cross-sectional study in local coffee shops in Singapore, Indonesia and India to measure the diterpene content in coffee, and a population-based study in Singapore to examine the relationship of coffee consumption and blood lipid levels. Interviews and coffee samples (n=27) were collected from coffee shops in Singapore, Indonesia and India. In addition, 3000 men and women who were Chinese, Malay, and Indian residents of Singapore participated in a cross-sectional study. RESULTS AND DISCUSSION: The traditional 'sock' method of coffee preparation used in Singapore resulted in cafestol concentrations comparable to European paper drip filtered coffee (mean 0.09±SD 0.064 mg/cup). This amount would result in negligible predicted increases in serum cholesterol and triglyceride concentrations. Similarly low amounts of cafestol were found in Indian 'filter' coffee that used a metal mesh filter (0.05±0.05 mg/cup). Coffee samples from Indonesia using the 'sock' method (0.85±0.41 mg/cup) or a metal mesh filter (0.98 mg/cup) contained higher amounts of cafestol comparable to espresso coffee. Unfiltered coffee from Indonesia contained an amount of cafestol (4.43 mg/cup) similar to Scandinavian boiled, Turkish and French press coffee with substantial predicted increases in serum cholesterol (0.33 mmol/l) and triglycerides (0.20 mmol/l) concentrations for consumption of 5 cups per day. In the Singaporean population, higher coffee consumption was not substantially associated with serum lipid concentrations after adjustment for potential confounders [LDL-cholesterol: 3.07 (95% confidence interval 2.97-3.18) for <1 cup/week versus 3.12 (2.99-3.26) for ≥3 cups/day; p trend 0.12]. CONCLUSIONS: Based on the low levels of diterpenes found in traditionally prepared coffee consumed in Singapore and India, coffee consumption in these countries does not appear to be a risk factor for elevation of serum cholesterol, whereas samples tested from Indonesia showed mixed results depending on the type of preparation method used.

A UHPLC-MS/MS Method for the Detection of Meat Substitution by Nine Legume Species in Emulsion-Type Sausages.

Meat substitution by legume proteins in various types of meat products is a common practice. A reliable detection and quantification of these additives is required to control food specifications, especially regarding food fraud. Consequently, a UHPLC-MS/MS method for the simultaneous detection of alfalfa (Medicago sativa), broad bean (Vicia faba), chickpea (Cicer arietinum), lentil (Lens culinaris), lupine (Lupinus albus and Lupinus angustifolius), pea (Pisum sativum), peanut (Arachis hypogaea), and soy (Glycine max) proteins in meat products was developed. After protein extraction and tryptic digestion, three marker peptides for each legume species were measured by multiple reaction monitoring (MRM) using an optimized extraction protocol. To the best of our knowledge, the marker peptides for alfalfa, broad bean, chickpea, and lentil have not been reported previously. Emulsion-type sausages with 0.1, 0.4, 0.7, 1.0, 1.3, 1.6, 1.9, 2.2, and 2.5% meat substitution by each legume species, representing the concentration range between inadvertently transferred cross-contaminations and the conscious use for meat substitution, were produced for matrix calibration. No false-positive results were recorded in blank samples. In the quantification of alfalfa, broad bean, chickpea, lentil, pea, peanut, and soy, 673 of 756 measuring data of the recovery rate in unknown sausages were in the accepted range of 80-120%.

Differentiation of Honeydew Honeys from Blossom Honeys and According to Their Botanical Origin by Electrical Conductivity and Phenolic and Sugar Spectra.

Honeydew honey, due to its higher antibacterial and antioxidant activity in comparison to blossom honeys, is in high demand and of interest to consumers. Although a differentiation of blossom honeys from honeydew honeys by way of electrical conductivity is given in many cases, criteria for a differentiation of individual honeydew honeys, such as spruce, fir, and pine, however did not exist. For this reason, 93 authentic honeydew honeys and 63 non-honeydew honeys [35 blossom and 28 nectar-honeydew (mixed)] from 13 different botanical origins were collected within the framework of the current study, and their electrical conductivity and phenolic and sugar profiles were investigated. Results showed that the higher electrical conductivity (≥0.80 mS/cm), the higher protocatechuic acid content (≥3.5 mg/kg), and the higher percentage of the oligosaccharide content (≥120 mg/g) were suitable parameters for the differentiation of authentic coniferous honeydew honeys from non-honeydew honeys; a differentiation. A differentiation of the spruce, fir, and pine honeydew honeys however could not be reached. Through the analysis of 32 carbohydrates (2 mono-, 7 di-, 10 tri-, and 13 higher oligosaccharides) in only one run by high-performance liquid chromatography equipped with an evaporative light scattering detector, marker substances can now be utilized for the classification of individual honeydew honeys. Sugar marker compounds such as α,α-trehalose, melezitose, theanderose, nystose, or maltotetraose in honeydew honeys in combination with chemometrics highlighted the good capability of sugar profiles to discriminate the honeydew honeys both from the non-honeydew honeys and from each other. All in all, a 96.75% correct classification of all studied 156 honey samples was achieved by sugar marker compounds.

A sensitive GC-HRMS method for the simultaneous determination of parent and oxygenated polycyclic aromatic hydrocarbons in barbecued meat and meat substitutes.

A sensitive GC-HRMS method was developed to analyze six polycyclic aromatic hydrocarbons (PAH; anthracene, benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, chrysene, and fluorene) and eight oxygenated PAHs (OPAH; anthracene-9,10-dione, benzo[a]anthracene-7,12-dione, 7H-benz[de]anthracene-7-one, 11H-benzo[b]fluorene-11-one, 6H-benzo[cd]pyren-6-one, 9,10-dihydro-8H-benzo[a]pyren-7-one, fluoren-9-one, and naphthacene-5,12-dione) in barbecued meat and meat substitutes. After optimization of the conditions of the sample preparation, consisting of accelerated solvent extraction (ASE) and solid-phase extraction (SPE), high recoveries (PAH 72-109%; OPAH 74-106%) were obtained. The linear regression of the matrix calibration resulted in high correlation coefficients (0.959-0.999). For the first time, reasonably low limits of detection (PAH 0.03-0.17 µg/kg; OPAH 0.04-0.43 µg/kg) were achieved, allowing the analysis of samples barbecued under practical relevant conditions. In charcoal grilled samples, the sum content of the seven detected OPAHs (5.7-62.4 µg/kg) was higher than the sum content of the six PAHs (1.4-36.7 µg/kg). However, 9,10-dihydro-8H-benzo[a]pyren-7-one was not detected in these samples.

Cornflower Honey as a Model for Authentication of Unifloral Honey Using Classical Methods Combined with Plant-Based Marker Substances Such as Lumichrome.

According to legislation, unifloral honeys are characterized by their organoleptic, physicochemical, and microscopic properties. Melissopalynology is the established method for identifying the pollen taken up with the floral nectar by forager bees and is used for authentication of the nectar sources in honey. For cornflower honey (Centaurea cyanus), the pollen input does not correlate with the nectar input, because the nectar is produced both in floral and in extrafloral nectaries. The well-known cornflower marker lumichrome has now also been detected in the extrafloral nectar. Therefore, lumichrome is a suitable marker substance for cornflower honey. Four different methods for the sole analysis of lumichrome in honey were validated and compared. Studies over nine years have shown that unifloral cornflower honey should contain approximately 35 mg/kg lumichrome. For a further differentiated cornflower honey specific verification, other nonvolatile compounds like 7-carboxylumichrome and volatiles, such as 3,4-dihydro-3-oxoedulan I and 3,4-dihydro-3-oxoedulan II, should be analyzed. This enables a more specific accuracy for the classification of unifloral cornflower honey.

Simultaneous analysis of 70 pesticides using HPlc/MS/MS: a comparison of the multiresidue method of Klein and Alder and the QuEChERS method.

Since 2003, two new multipesticide residue methods for screening crops for a large number of pesticides, developed by Klein and Alder and Anastassiades et al. (Quick, Easy, Cheap, Effective, Rugged, and Safe; QuEChERS), have been published. Our intention was to compare these two important methods on the basis of their extraction efficiency, reproducibility, ruggedness, ease of use, and speed. In total, 70 pesticides belonging to numerous different substance classes were analyzed at two concentration levels by applying both methods, using five different representative matrixes. In the case of the QuEChERS method, the results of the three sample preparation steps (crude extract, extract after SPE, and extract after SPE and acidification) were compared with each other and with the results obtained with the Klein and Alder method. The extraction efficiencies of the QuEChERS method were far higher, and the sample preparation was much quicker when the last two steps were omitted. In most cases, the extraction efficiencies after the first step were approximately 100%. With extraction efficiencies of mostly less than 70%, the Klein and Alder method did not compare favorably. Some analytes caused problems during evaluation, mostly due to matrix influences.

Effect of fragaria vesca, hamamelis and tormentil on the initial bacterial colonization in situ.

OBJECTIVE: The presentin situ study aims to examine the influence of the polyphenolic tea drugs fragaria vesca, hamamelis and tormentil on the initial oral bioadhesion. DESIGN: Initial biofilm formation was performed on bovine enamel slabs which were carried intraorally by 12 subjects. After 1 min of intraoral pellicle formation, the subjects rinsed with fragaria vesca, tormentil (0.8 mg/8 mL) and hamamelis (0.2 mg/8 mL) for 10 min. Tap water served as negative control, 0.2 % CHX as positive control. The investigations took place on different days (wash-out: 2 days). Afterwards, fluorescence microscopy has been performed per test solution (n = 5) and per subject (n = 12) to visualize bacterial adhesion and glucan formation (8 h oral exposition) with DAPI, ConA and BacLight. Additionally, TEM was used to visualize the pellicle ultrastructure and expectorate samples. Statistical evaluation was carried out using the Kruskal-Wallis- (p < 0.5), Mann-Whitney U test (p < 0.5) and Bonferroni-Holm-correction (p < 0.1). RESULTS: Rinsing with the polyphenolic tea extracts reduced significantly initial bacterial colonization (DAPI) compared to the negative control. There was no significant difference betweenfragaria vesca, hamamelis and tormentil. All solutions showed a reducing effect on the glucan formation. No significant difference was observed between fragaria vesca and CHX. Considerable alterations of the pellicle's ultrastructure manifested by an increase in thickness and electron density resulted from rinsing with the three polyphenolic aqueous extracts. CONCLUSIONS: Fragaria vesca, hamamelis and tormentil significantly reduce initial bioadhesion and glucan formation in situ and are therefore recommended as adjuvant antibacterial oral therapeutics.

New approaches for determination of glyphosate and aminomethylphosphonic acid from different tea samples--prospects and limits of cleanup with molecularly imprinted polymer and titanium dioxide.

Glyphosate is the most commonly used herbicide worldwide. To identify glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), in the difficult-to-analyze matrix of tea, new methods were developed. The main emphasis was placed on the cleanup procedure. Two different solid-phase extraction methods were tested and evaluated: one with molecularly imprinted polymers, and the other with immobilized titanium dioxide. The optimization was carried out on the basis of aqueous standard solutions and spiked tea extracts. Validated results were presented for pipet tips that contained immobilized titanium dioxide. After the extraction of glyphosate from tea samples using hydrochloric acid (0.1%), glyphosate and AMPA were concentrated on the adsorbent by pipetting up and down several times without changing the tip. The elution was carried out subsequent to a washing step with 5% ammonia. The extract was derivatized with 2,2,2-trifluoroacetic acid and 2,2,2-trifluoroethanol and then analyzed by GC with MS detection in the negative chemical ionization mode. Quantification was carried out in the selected-ion monitoring mode based on the m/z ratio of characteristic ions due to the ionization process. For glyphosate m/z = 370 was applied, and m/z = 351 for AMPA. The detection limit was 0.03 mg/kg tea for glyphosate and 0.006 mg/kg tea for AMPA. The recoveries for the tested working range (0.1 to 2.8 mg/kg tea) were low but constant at 14 and 12%, respectively. Altogether, the method presented here can be carried out easily and quickly, and it gives reliable information on the presence of the analytes in a sample. Quantification is also possible using standard addition.

Influence of Smoking and Barbecuing on the Contents of Anthraquinone (ATQ) and Polycyclic Aromatic Hydrocarbons (PAHs) in Frankfurter-Type Sausages.

The contents of anthraquinone (ATQ) and polycyclic aromatic hydrocarbons (anthracene (ANT) and PAH4) in smoked Frankfurter-style sausages were investigated depending on various smoking conditions. During smoking, the smoke generator, the smoking duration, the type of wood, and some more plant-specific parameters were tested. The sausages were also barbecued on a charcoal grill. The lowest mean contents of all analytes were observed when friction smoke was used (ATQ < limit of quantification (LOQ); ANT < LOQ; PAH4 < limit of detection (LOD)) and the highest when the settings of ventilations flaps were changed (ANT 36.3 µg/kg; PAH4 2.2 µg/kg) or at an intensive smoke density (ATQ 3.2 µg/kg). The contents increased with the smoking time, but irregularities were detected after 10 min. The use of different types of wood had no influence on the ATQ content but affected the PAH content. In barbecued samples, ATQ and ANT contents were detected at the level of friction smoke and maximum PAH4 contents were found above the exposure during smoking. Due to the varying influence of the smoking parameters on the two analytes, there was no direct correlation between the contents of ATQ and ANT in all smoking experiments.

Simultaneous determination of pesticides, mycotoxins, and metabolites as well as other contaminants in cereals by LC-LC-MS/MS.

A 2D LC-MS/MS method for the simultaneous determination of 350 pesticides, 16 mycotoxins as well as the growth regulators Chlormequat and Mepiquat was developed. The method is applicable to cereals and products thereof. Attention should be paid to the simultaneous analysis of the cereal-relevant mycotoxins aflatoxin B1, B2, G1 and G2, ochratoxin A, deoxynivalenol and zearalenone. Moreover, the tropane alkaloids atropine/scopolamine could be integrated into the final method. The samples were extracted with a mixture of acetonitrile/water (80:20), diluted with acetonitrile and injected into an LC-LC-MS/MS system. There were no further manual clean-up steps. The automatic online clean-up took place during the HILIC-separation in the first dimension (YMC-Pack Diol; 2.1 × 100 mm; 5 µm, 120 Å). Here, polar matrix compounds were retained, while the majority of the analyte scope eluted in a fraction at the beginning of the analytical run. This fraction was transferred to the second dimension by a packed loop interface (Agilent Zorbax SB-C8; 4.6 × 12.5 mm; 5 µm; 80 Å). On the second column (Phenomenex Synergi Fusion RP C18; 2 × 100 mm; 2.5 µm; 100 Å), the majority of the scope was separated by a typical RP-gradient. Only some of the polar pesticides could not be transferred to the second column. They eluted directly after the transfer step from the HILIC-column to the MS/MS. The final method was sensitive enough to meet all the regulated maximum levels for pesticides in cereals according to EU Regulation 396/2005 and those for contaminants according to EU Regulation 1881/2006. Above all, the method was so robust and accurate that nearly 90% of the pesticides and all the tested mycotoxins, growth regulators and tropane alkaloids fulfilled the validation criteria of the SANTE guideline document, although the demanding criteria are only applicable to pesticides. For the verification, eight proficiency tests were passed successfully: three for the pesticide analysis, three for the mycotoxin analysis, and two for the analysis of the tropane alkaloids. In addition to the already mentioned contaminants, the six most important ergot alkaloids (e.g. ergotamine/ergotaminine) and two modified mycotoxins (deoxynivalenol-3-glucoside and zearalenone-sulfate, also known as masked mycotoxins) were detected during the routine analysis of rye and corn samples.