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Summary: This study aimed to elucidate the information mechanism of advanced glycation end products (AGEs) in sturgeon fillets, and its inhibition by polyphenol. The results revealed that LTVH fillets (processed using low temperature vacuum heating method, LTVH) did not have lower values of AGEs than those treated using TC method (a typical thermal procedure using boiling water at 100 °C). The addition of tea polyphenol, on the other hand, drastically reduced the AGEs levels in LTVH fillets. An in vitro model including sturgeon myofibrillar protein and glucose was employed in this work to evaluate the inhibition of AGEs by tea polyphenol. The results showed that free Arginine was susceptible to interaction with glucose, which caused the development of AGEs. However, the addition of tea polyphenol competed with glucose for binding to free Arginine, leading to a substantial decrease in free Arginine concentration and an increase of free amino loss rate, resulting in the inhibition of AGEs generation. The LTVH technique, in combination with tea polyphenol, can be used to prevent the production of AGEs on fillets during the thermal treatment. [ABSTRACT FROM AUTHOR]

Summary: The superheated steam temperature system of the thermal power plant has the characteristics of large inertia, nonlinearity, and strong time variation, which make it difficult to be controlled. To address these problems, this paper proposes a generalized predictive control algorithm with an adaptive forgetting factor. First, based on a fuzzy algorithm and a recursive least squares algorithm, the controlled object's model can be quickly and accurately obtained with the adaptive forgetting factor in real time. It overcomes the nonlinear and time‐varying problems of the controlled object in the control progress. Meanwhile, it also solves the problem of data saturation and the weight assignment of the "new and old" data during online identification. Second, an adaptive generalized predictive controller algorithm has been developed with the controlled object. It solves the large inertia problem of the controlled object. Finally, through establishing simulation model of the superheated steam temperature system and simulating, the results show that the proposed method has better control performance, antidisturbance ability, adaptability, and robustness. Moreover, it has a certain reference significance for the design of a practical control system. [ABSTRACT FROM AUTHOR]

Abstract: To detect and quantify synephrine in feed, an effective analytical method based on quick, easy, cheap, effective, rugged, and safe solid‐phase extraction coupled to ultra high performance liquid chromatography with tandem mass spectrometry was developed with isotopic internal standards. Pretreatment was performed using quick, easy, cheap, effective, rugged, and safe solid‐phase extraction with primary secondary amine and C18 sorbent as sorbents in combination with Oasis MCX column clean‐up to extract and purify feed samples. Tandem mass spectrometry detection in positive ion mode was conducted in positive multiple reaction monitoring mode in addition to the quantitative internal standard method. Two transitions of synephrine at m/z 168.1/150.0 and 168.1/135.0 were selected, and m/z 168.1/135.0 was determined as the quantification ion pair. D9‐Terbutaline was selected as an internal standard, for which m/z 235.1/153.0 was selected as the quantification ion pair. Good linearity was shown for synephrine in the range of 0.5–50 μg/L, and the correlation coefficient exceeded 0.999. The recoveries in three different feed samples at three spiked levels were 81.42–112.08%, and the relative standard deviations were not greater than 14.66%. The method proposed in this study was reliable and highly effective, and its sensitivity, accuracy, and precision are suitable for determining synephrine residues in feed samples. [ABSTRACT FROM AUTHOR]

Strobilurins constitute a new class of fungicides that is the most widely used in the world. The present study was conducted to investigate the aquatic toxicity of 3 common strobilurin fungicides (kresoxim-methyl, pyraclostrobin, and trifloxystrobin) to Daphnia magna. The neonate acute immobilization test showed that the 48-h 50% effective concentration (EC50) values of kresoxim-methyl, pyraclostrobin, and trifloxystrobin were 443.3µg/L, 20.9µg/L, and 23.0µg/L, respectively. In addition, the 3 strobilurins significantly induced activity of the important detoxification enzyme glutathione S-transferase (GST) in D. magna, and there was a significant positive relationship between GST activity and immobility of D. magna after acute exposure. The 3 strobilurins showed higher toxicity to D. magna embryos, and the 48-h EC50 were 157.3µg/L, 3.9µg/L, and 1.7µg/L for kresoxim-methyl, pyraclostrobin, and trifloxystrobin, respectively. The 21-d chronic test revealed that the strobilurins could also significantly affect the reproduction, development, and growth of D. magna at sublethal concentrations. The lowest-observed-effect concentrations of kresoxim-methyl, pyraclostrobin, and trifloxystrobin for reproduction were 20µg/L, 0.15µg/L, and 0.2 µg/L, respectively, which were close to environmental concentrations. The findings indicate that strobilurin fungicides are very toxic to D. magna and they are sufficient to cause harm to D. magna at environmentally relevant concentrations. [ABSTRACT FROM AUTHOR]

The enantiomeric separation of eight pesticides including bitertanol ( 1), diclobutrazol ( 2), fenbuconazole ( 3), triticonazole ( 4), imazalil ( 5), triapenthenol ( 6), ancymidol ( 7), and carfentrazone-ethyl ( 8) was achieved, using normal-phase high-performance on two cellulosed-based chiral columns. The effects of isopropanol composition from 2% to 30% in the mobile phase and column temperature from 5 to 40 °C were investigated. Satisfactory resolutions were obtained for bitertanol ( 1), triticonazole ( 4), imazalil ( 5) with the (+)-enantiomer eluted first and fenbuconazole ( 3) with the (-)-enantiomer eluted first on Lux Cellulose-2 and Lux Cellulose-3. (+)-Enantiomers of diclobutrazol ( 2) and triapenthenol ( 6) were first eluted on Lux Cellulose-2. (-)-Carfentrazone-ethyl ( 8) were eluted first on Lux Cellulose-2 and Lux Cellulose-3 with incomplete separation. Reversed elution orders were obtained for ancymidol (7). (+)-Ancymidol was first eluted on Lux Cellulose-2 while on Lux Cellulose-3 (-)-ancymidol was first eluted. The results of the elution order at different column temperatures suggested that column temperature did not affect the optical signals of the enantiomers. These results will be helpful to prepare and analyze individual enantiomers of chiral pesticides. Chirality 27:32-38, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

An enantioselective method was developed for the simultaneous detection of five chiral fungicides in soil, including fenbuconazole ( 1), tetraconazole ( 2), nuarimol ( 3), triticonazole ( 4), and simeconazole ( 5) by LC-MS/MS on a chiral stationary phase of cellulose tris-(3-chloro-4-methylphenylcarbamate) with a gradient elution. A new multifunctional filter was designed to simplify the QuEChERS (where QuEChERS is quick, easy, cheap, effective, rugged, and safe) method by simultaneous cleanup and filtration when the sample extracts were directly passed through it. Good linearities ( R2 > 0.9980) were obtained in the range 0.005-2.5 mg/L, and the recovery rates were 77.4-103.6% with RSDs of 0.7-12.2% for intraday precision and 1.2-11.0% for interday precision. The LODs and LOQs for all enantiomers were in the range 0.1-0.2 and 0.25-0.5 μg/kg, respectively. The analysis of the incubated soil suggests that this method is reliable and practical for the stereoselective detection of chiral fungicides. [ABSTRACT FROM AUTHOR]