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Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bongkrekic acid (BA) and isobongkrekic acid (IBA) are produced by the bacterium Burkholderia gladioli pv. Cocovenenans (B. cocovenenans) associated with outbreaks of foodborne diseases involving coconut and corn-based products in Indonesia, China and Mozambique. Bongkrekic acid and isobongkrekic acid are littleknown mitochondrial toxins that inhibit adenine nucleotide translocase (ANT). The latency period after exposure to BA and IBAcontaminated foods is reported to be 224 hours. The symptoms of poisoning include discomfort of digestive system and nervous system. Serious patients will die from multiple organ failure, such as liver, brain and kidney. The mortality rate from past outbreaks in China was about 40%, and that in Indonesia was about 60%. The method of ultraperformance liquid chromatographic method coupled with triple quadrupole tandem mass spectrometry (UPLCMS/MS) was established for determination of bongkrekic acid and isobongkrekic acid in plasma and urine. Isobongkrekic acid was prepared by treating of bongkrekic acid with 2 mol/L KOH for 2 h at 100 ℃, and confirmed with the reference substance by mass spectrometry, chromatography and ultraviolet spectroscopy. The main factors including methods of sample pretreatment, separation column types, compositions of mobile phases, and instrumental conditions of mass spectrometry were optimized. The bongkrekic acid and isobongkrekic acid in plasma were ultrasonically extracted with acetonitrilemethanol (9∶1, V/V) solution containing 05% (V/V) ammonia solution, and then the extract was centrifuged to remove the impurities, such as proteins. After acetonitrile and methanol in extract were removed, the analytes in the residues were extracted by hexane under pH 1520. The bongkrekic acid and isobongkrekic acid in urine were directly extracted by hexane under pH 1520. The chromatographic analysis was separated on an Acquity BEH C18 column (21 mm×100 mm×17 μm) with gradient elution of using mobile phases of acetonitrile and water both containing 0.05% (V/V) formic acid. A triple quadrupole mass spectrometer, equipped with electrospray ionization (ESI) in the negative ion mode, was used to detect bongkrekic acid and isobongkrekic acid in multiple reaction monitoring (MRM) mode. Bongkrekic acid and isobongkrekic acid were quantitated by external standard of matrix working curve. The linear ranges of the analytes were from 005 μg/L to 10 μg/L with the correlation coefficients greater than 0998. The limits of detection (LODs) of bongkrekic acid and isobongkrekic acid in plasma and urine were 002 μg/L, and the limits of quantification (LOQs) of them were 005 μg/L. The average recoveries were 92%106% with the relative standard deviations of 24%13%. The method is simple, sensitive and accurate, and can be used for the detection of bongkrekic acid and isobongkrekic acid in plasma and urine poisoned by Burkholderia gladioli pv. Cocovenenans. [ABSTRACT FROM AUTHOR]

Sodium monofluoroacetate is a rodenticide with high acutetoxicity. Although banned for use in China, sodium monofluoroacetate is still commonly used in New Zealand, Australia, Israel and the USA. Fluoroacetate also exists naturally in many botanical species worldwide. The obtainability and stability of sodium monofluoroacetate and its proximity to agricultural products could potentially lead to the accidental or intentional contamination of food. In this work, a simple and sensitive method of ion chromatography triple quadrupole mass spectrometry (IC-MS/MS) was developed for the determination of sodium monofluoroacetate in dairy powders and infant formulas. The main factors including sample pretreatment and instrumental conditions of ion chromatography-triple quadrupole mass spectrometry were optimized. The sodium monofluoroacetate in dairy powder sample was ultrasonically extracted with aqueous solution containing 3% perchloric acid, and then the extract was centrifuged to remove the impurities, such as protein and lipid. The monofluoroacetic acid in the mixture was extracted by methyl tert-butyl ether (MTBE) under pH 0.5-1.0. After the MTBE was removed by N2, the monofluoroacetic acid in the residues was dissolved into 0.1% ammonia solution. The ion chromatographic analysis was separated on a Dionex IonPac AS 19 analytic column (2 mm×250 mm×7.5 μm) with gradient elution of using eluent of KOH solution electrolytically generated from on-line eluent generation cartridge. An in-line suppressor was used to remove potassium ion from the eluent before the eluent flow entered the mass spectrometer. A triple quadrupole mass spectrometer, equipped with electrospray ionization (ESI) in negative ion mode was used to detect monofluoroacetate anion in multiple reaction monitoring (MRM) mode. A 13C2-labeled monofluoroacetate anion internal standard was used to correct for any matrix effects. The results showed that the linear range of the sodium monofluoroacetate was 0.3-1300 μg/L with the correlation coefficients greater than 0.999. The limit of detection (LOD) and the limit of quantification (LOQ) of sodium monofluoroacetate were 0.2 μg/kg and 0.6 μg/kg, respectively. The recoveries were 89.7%-104%, and the relative standard deviations were 0.50%-11%. The method is simple, sensitive and accurate, and has been applied to the measurement of sodium monofluoroacetate in dairy powders and infant formulas, and also can be applied to the detection of target compound in other poisoning food samples. [ABSTRACT FROM AUTHOR]

Ribavirin is antiviral agent for the treatments of influenza A virus infections. Due to the potential resistance for human beings, ribavirin has been banned as antiviral agent during poultry farming in many countries. Nevertheless, this antiviral drug may be still illegally used for the treatment of avian influenza in poultry farming. Therefore, it is necessary to develop a sensitive method for the analysis of ribavirin in chicken muscle tissues and eggs. A simple and sensitive method for the determination of total residues of ribavirin in chicken muscle tissues and egg by heart-cutting two-dimensional high performance liquid chromatography-triple quadrupole/linear ion trap mass spectrometry was developed. The main factors influencing the purification and separation efficiency including methods of sample pretreatment, column types of purification and separation, compositions of mobile phases, times of valve switch, and instrumental conditions of mass spectrometry were optimized. During analysis of two types of matrixes (chicken and egg), the matrix effects of ribavirin under these conditions were evaluated. Under the optimal conditions, the matrix effects of ribavirin in chicken and eggs were 48.9% and 74.2%, respectively. The optimal extraction conditions were as follows: 2.00 g sample was extracted with 10 mL of 0.10 mol/L ammonium acetate buffer (pH 4.8) under enzymatically hydrolyzed for 2 h with acid phosphatase at 37 ℃, and then the extraction was centrifuged for 5 min at speed of 12 000 r/min and the supernatant was ultrafiltrated. The first dimension separation of ribavirin was carried out on a Zorbax SB-Aq column (3.0 mm×150 mm×1.8 μm) with elution with 0.2% formic acid aqueous solution. The flow rate was 0.400 mL/min, and the retention time of ribavirin was 2.32 min. During chromatographic ran for 2.10 to 2.50 min, the fraction containing ribavirin was switched into a Hypercarb PGC guard column (4.6 mm×10 mm×5 μm). After the trap column retained completely the ribavirin, it was switched into the stream of 2nd dimension chromatographic system, the ribavirin was separated on a Hypercarb PGC column (2.1 mm×150 mm×3 μm) with gradient elution of acetonitrile-aqueous solution containing 0.1% formic acid, and detected by positive electrospray ionization mass spectrometry in the multiple reaction monitoring-information-dependent acquisition-enhanced product ion (MRM-IDA-EPI) scanning mode, and quantified by stable isotope internal standard method. The correlation coefficient of linear calibration cuve of ribavirin is better than 0.999 at the corresponding concentration range of 0.1-100 μg/L. The average recoveries are 87.5%-97.7% for ribavirin in chicken and eggs with relative standard deviations of 2.8%-8.3% (n=6). The limit of detection and quantification of ribavirin are 0.2 and 0.7 μg/kg, respectively. The method is simple, sensitive and selective, and has been successfully applied to the total residue determination of ribavirin in chicken and egg samples. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Ritual, Theatre & Folklore / Mínsú Qǔyì is the property of Shih Ho-Cheng Folk Culture Foundation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)