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A high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS) method was developed for simultaneous determination of 20 Fusarium toxins (nivalenol, fusarenon-X, deoxynivalenol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, HT-2 toxin, T-2 toxin, neosolaniol, diacetoxyscirpenol, fumonisin B1, fumonisin B2, fumonisin B3, fumonisin A1, fumonisin A2, fumonisin A3, zearalenone, α-zearalenol, β-zearalenol, α-zearalanol, and β-zearalanol) in cereals. The separation of 20 Fusarium toxins with good peak shapes was achieved using a pentafluorophenyl column, and Orbitrap MS was able to detect accurately from cereal matrix components within ±0.77 ppm. The samples were prepared using a QuEChERS kit for extraction and a multifunctional cartridge for purification. The linearity, repeatability, and recovery of the method were &gt, 0.9964, 0.8%–14.7%, and 71%–106%, respectively. Using this method, an analysis of 34 commercially available cereals detected the presence of deoxynivalenol, 15-acetyl deoxynivalenol, fumonisin B1, fumonisin B2, fumonisin B3, fumonisn A1, fumonisin A2, fumonisin A3, and zearalenone in corn samples with high concentration and frequency. Trichothecenes was detected from wheat samples with high frequency, in particular, the concentration of deoxynivalenol was high. Conversely, α-zearalenol, β-zearalenol, α-zearalanol, and β-zearalanol were not detected in any of the samples.

Three compounds, hypothesized as fumonisin A1 (FA1), fumonisin A2 (FA2), and fumonisin A3 (FA3), were detected in a corn sample contaminated with mycotoxins by high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS). One of them has been identified as FA1 synthesized by the acetylation of fumonisin B1 (FB1), and established a method for its quantification. Herein, we identified the two remaining compounds as FA2 and FA3, which were acetylated fumonisin B2 (FB2) and fumonisin B3 (FB3), respectively. Moreover, we examined a method for the simultaneous analysis of FA1, FA2, FA3, FB1, FB2, and FB3. The corn samples were prepared by extraction using a QuEChERS kit and purification using a multifunctional cartridge. The linearity, recovery, repeatability, limit of detection, and limit of quantification of the method were &gt, 0.99, 82.9%–104.6%, 3.7%–9.5%, 0.02–0.60 μg/kg, and 0.05–1.98 μg/kg, respectively. The simultaneous analysis of the six fumonisins revealed that FA1, FA2, and FA3 were present in all corn samples contaminated with FB1, FB2, and FB3. The results suggested that corn marketed for consumption can be considered as being contaminated with both the fumonisin B-series and with fumonisin A-series. This report presents the first identification and quantification of FA1, FA2, and FA3 in corn samples.

Fumonisin A-series (FAs) in a reference material of corn sample that was naturally contaminated with fumonisins was characterized using high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitap MS). Peaks for fumonisin B1 (FB1), fumonisin B2 (FB2), and fumonisin B3 (FB3), in addition to three peaks corresponding to unknown compounds I, II, and III, were detected in the chromatogram for the corn sample. Fragment ion analysis for FB1, FB2, and FB3 showed that while the ions formed at m/z values of 200-800 were similar to those formed by the cleavage of the tricarballylic acids and the hydroxyl groups, the fragmentation patterns at m/z values of 50-200 varied depending on the hydroxyl group locations in the compounds. Fragment ion analysis of compounds I-III revealed structural similarities to FBs, only differing by an additional C2H2O in the unknown compounds. Using these results and by comparing the product ion mass spectra of compound I with fumonisin A1 (FA1) synthesized from FB1 standards, compounds I-III were hypothesized to be N-acetyl analogs of FBs: fumonisins A1 (FA1), A2 (FA2), and A3 (FA3). The method for determining concentrations was validated with FA1, FB1, FB2, and FB3 standards and applied to analyze the reference material. The FB1, FB2, and FB3 analytical levels were within acceptance limits and the amount of FA1 in the material was ~15% of FB1 amount at 4.2 mg/kg. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

A method for the simultaneous analysis of 14 mycotoxins with the minimization of carryover was developed. Our verification experiments suggested that the carryover occurred due to the chelation of fumonisins with the metal. To wash the fumonisins from the metal, the inner surface of the injection needle was rinsed with 10 mM trisodium citrate and 1% formic acid in water/methanol/acetonitrile/isopropanol after each injection, and the analysis was performed on a metal-free Mastro C18 column. This approach remarkably minimized the carryover of fumonisins. Fourteen mycotoxins in samples were extracted with 2% acetic acid in water/acetonitrile and a quick, easy, cheap, effective, rugged, and safe extraction kit, purified on a MultiSep 229 Ochra, and then quantified by liquid chromatography with tandem mass spectrometry. Determinations performed using this method produced a linearity greater than 0.99 and recoveries ranging from 72.6 to 117.4%, with good intraday precision from 4.0 to 12.4%, and interday precision from 6.5 to 17.0%. The limits of detection ranged from 0.01 to 0.71 μg/kg, demonstrating that a highly sensitive method for the simultaneous analysis of mycotoxins over a wide range of concentrations was achieved with minimal carryover. When 12 samples of commercially available corn grits were analyzed with this method, deoxynivalenol, fumonisin B1, fumonisin B2, fumonisin B3, and zearalenone were present most frequently.

We developed a method for simultaneous analysis of nine trichothecenes (nivalenol, deoxynivalenol, fusarenon-X, neosolaniol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, diacetoxyscirpenol, HT-2 toxin, and T-2 toxin). Trichothecenes in samples were extracted with acetonitrile-water (1 : 1) and purified using a QuEChERS kit and a multi-functional cartridge. Then they were quantified by LC-MS/MS using internal standards. LC with a pentafluorophenyl column and a mobile phase containing methanol enabled complete separation and highly sensitive quantification of the nine trichothecenes. Method validation with powdered corn soup samples demonstrated high linearity (>0.99) and accuracy ranging from 95% to 111% with good repeatability of 0.9% to 6.6% and reproducibility of 0.6% to 11.6%. The limits of detection and quantification were 0.01 to 0.75 μg/kg and 0.04 to 2.50 μg/kg, respectively. When 15 samples from powdered corn soups on the market were analyzed with this method, deoxynivalenol was detected in two samples (20.7 and 22.5 μg/kg, respectively), and 3-acetyldeoxynivalenol was concomitantly detected in one of them (13.5 μg/kg).

A chromanone glycoside, 5-β- d -glucopyranosyloxy-7-hydroxy-2-isopropylchromanone, and two acylphloroglucinol glycosides, 2-(3-methylbutyryl)phloroglucinol-4,6-di-C-β- d -glucopyranoside and 2-isobutyrylphloroglucinol-1,5-di-O-β- d -glucopyranoside, along with 15 known compounds were isolated from the bracts of hops (Humulus lupulus L.). Their structures were elucidated based on spectroscopic data, including TOFMS and 1D/2D NMR.

An analytical method using two solid phase extractions and ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed for the identification and quantification of 14 mycotoxins (patulin, deoxynivalenol, aflatoxins B1, B2, G1, G2, M1, T-2 toxin, HT-2 toxin, zearalenone, fumonisins B1, B2, B3, and ochratoxin A) in domestic and imported wines. Mycotoxins were purified with an Oasis HLB cartridge, followed by a MultiSepTM #229 Ochra. As a result, sufficient removal of the pigments and highly polar matrices from the red wines was achieved. UHPLC conditions were optimized, and 14 mycotoxins were separated in a total of 13 min. Determinations performed using this method produced high correlation coefficients for the 14 mycotoxins (R > 0.990) and recovery rates ranging from 76 to 105% with good repeatability (relative standard deviation RSD < 12%). Twenty-seven samples of domestic and imported wines were analyzed using this method. Although ochratoxin A (OTA) and fumonisins (FMs) were detected in several samples, the FM levels were less than limits of quantification (LOQs) (1 μg/L), and even the largest of the OTA levels was below the EU regulatory level (2 μg/L). These results suggest that the health risk posed to consumers from the wines available in Japan is relatively low.

An HPLC method with a charged aerosol detector (CAD) was optimized and validated for the quantification of six carbohydrates (xylose, fructose, glucose, sucrose, lactose, maltose) and sugar alcohol (erythritol) in drinks. Chromatographic separation was achieved using gradient elution with a mixture of water-methanol (7 : 3) and acetonitril. Carbohydrates were cleaned up using a strong cation exchange cartridge (Bond Elut SCX, Varian). Although an interfering peak appeared without any clean up, it was confirmed that interfering substance had be removed by a treatment using this cartridge and its peak had disappeared. The determinations were performed in the linear range of 5 ∼ 10000 μg/mL for six carbohydrates and sugar alcohol, the correlation coefficients (R) were 0.998 ∼ 1.000, the relative standard deviations (RSDs) ranged over 0.4 ∼ 4.5% (spiked level at 500 μg/mL, n = 5), recoveries ranged between 84 ∼ 113% (spiked level at 500 μg/mL, n = 3), and the limits of quantification were 0.4 ∼ 19.3 μg/mL. In addition, we performed analysis of carbohydrates with CAD, an evaporative light scattering detector (ELSD) and a refractive index detector (RID) to compare and investigate the sensitivity and analysis precision in the each optimum condition. As for the CAD, high sensitivity and good analysis precision were provided. Because it is not necessary to optimize the conditions, CAD is the simplest and easiest device in these detectors. It became clear that CAD was the most suitable to perform correct quantitative analysis of carbohydrates in drinks.

A new method was established for the simultaneous determination of 10 sweeteners and a degradation product in beverages by using LC-MS/MS. An ACQUITY UPLC BEH C18 (2.1 × 100 mm, 1.7 μm) was used as the LC column and 0.1% each of aqueous formic acid and formic acid in acetonitrile were used as the mobile phase. A simple and rapid determination of sweeteners was possible by diluting with a solvent, and in the case of some samples containing a large amount of foreign matter, after pre-treatment by diluting with solvent and clean-up of the sample using an Oasis HLB cartridge. All the validation results were satisfactory. As the regulations and standards for sweeteners vary from country to country, a field survey of 58 beverages marketed in Japan was performed using the present method. No issues concerning the labelling or food sanitation law were found in the tested samples.

Harmonized collaborative validation of a simultaneous and multiple determination method for nivalenol, deoxynivalenol, T-2 toxin, HT-2 toxin, and zearalenone in wheat and barley by liquid chromatography tandem mass spectrometry (LC-MS/MS) was conducted by participants from 12 laboratories. The fortified samples of wheat and barley at three different levels and one naturally contaminated wheat sample were extracted, consecutively purified through a Presep C18 (ODS) solid phase extraction column and a Bond Elut Mycotoxin multifunctional column, and were analyzed by LC-MS/MS. The employment of internal standards (verrucarol and zearalanone) was apparently effective to ensure repeatability and reproducibility with sufficient recovery of each mycotoxin. This is the first report of the harmonized collaborative validation study of a simultaneous and multiple determination method for both type A and B trichothecenes along with zearalenone by LC-MS/MS. The validated method should be practical for monitoring of the major Fusarium mycotoxins contained in wheat and barley.

A novel cyanobacterial vector, pTT201, containing the bar gene encoding resistance to herbicides, bialaphos and phosphinothricin, was constructed. In Synechococcus sp. strain PCC7942-SPc, the bar gene was successfully expressed. Plasmid pTT201 increased a minimum inhibitory concentration for bialaphos 16-fold over Synechococcus sp. strain PCC7942-SPc without pTT201. The combination of the bialaphos as a selective agent and the transformation by bar gene serves as a photostable selection system for Synechococcus.

An analytical method was developed for the identification and quantification of 15 mycotoxins (patulin, nivalenol, deoxynivalenol, aflatoxin B(1), B(2), G(1), G(2), M(1), T-2 toxin, HT-2 toxin, zearalenone, fumonisin B(1), B(2), B(3), and ochratoxin A) in beer-based drinks (beer, low-malt beer, new genre, and nonalcoholic) by a modified QuEChERS method and an ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC/MS/MS). Mycotoxins were extracted from samples using acetonitrile with sodium chloride, anhydrous magnesium sulfate, and sodium citrate, and were then purified with a solid phase extraction (SPE) cartridge including C18. The UHPLC conditions were also examined to establish its optimal conditions for separation. Fifteen mycotoxins were separated in a total of 6.5 min, and were quantified in the optimal mobile phase conditions. Determinations performed using this method produced high correlation coefficients of 15 mycotoxins (R0.99) and recovery rates ranging from 70.3 to 110.7% with good repeatability (relative standard deviation RSD14.6%). Further, 24 commercial beer-based drinks in Japan were analyzed using this method, and nivalenol, deoxynivalenol, and fumonisins were detected in several samples, but always under the limit of quantification (5 ng/mL). These results suggest that the health risk to consumers from beer-based drinks in Japan is relatively low.