Ethanol-ammonium sulfate system based modified quick, easy, cheap, effective, rugged, and safe method for the determination of four neonicotinoid pesticide and metabolite residues in two canned fruits.

As the pesticide and its metabolite residues in processed fruits could become a significant route of human exposure. The work presented herein focuses on developing a feasible quick, easy, cheap, effective, rugged, and safe method with improved extraction and cleanup system for the determination of imidacloprid, acetamiprid, thiamethoxam, and clothianidin (a metabolite of thiamethoxam) in canned fruits. The low toxic solvent ethanol was used to extract the analytes, and ammonium sulfate was used to promote phase separation. Moreover, the carboxylated multi-walled carbon nanotube acted as the clean-up sorbent for the removal of high solubility impurities. The proposed method was validated with fortified real samples at different concentration levels (20-200 µg/kg). Recoveries obtained from three spiked levels (20, 50, and 200 µg/kg) ranged from 74.9 to 86.4% with relative standard deviations of the intra-day and inter-day in the range of 0.8-5.5 and 2.0-7.1%, respectively. The limits of detection ranged from 0.2 to 0.5 and 0.2 to 0.6 µg/kg for orange and peach, respectively. The results demonstrated that the proposed method could be considered appropriate, and comparatively lower toxic for the analysis of neonicotinoid pesticide residues in canned fruit.

Development of a fully automated analytical platform based on static headspace-gas chromatography-tandem mass spectrometry for the analysis of five N-nitrosamines in dried aquatic products of animal origin.

BACKGROUND: The development of rapid and sensitive monitoring methods for trace N-nitrosamines (NAs) in foodstuffs is essential for mitigating the potential health risks to consumers. In the present study, an analytical platform based on one step fully automated static headspace sampling and gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed and validated for the analysis of N-nitrosamines in dried aquatic products of animal origin. The samples and sodium chloride solution mixture were incubated in a heated headspace vial for analyte evaporation, coupled to automatic sampling and online GC-MS/MS analysis. The proposed method requires minimal sample preparation and organic solvent consumption. Five N-nitrosamines including N-nitroso dimethylamine, N-nitroso methyl ethylamine, N-nitroso pyrolidine, N-nitroso piperidine and N-nitroso diphenylamine were selected as model compounds to optimize the significant factors by a using Box-Behnken design. RESULTS: The optimum conditions achieved limits of detections in the range 0.08-0.29 µg kg-1 , with correlation coefficient over 0.998. Relative recoveries in dried aquatic product sample were in the range 76.9-92.4%, with relative SDs of 1.9-7.2%. CONCLUSION: These results confirm the reliability of the developed method for further application in trace level monitoring of the target analytes in foodstuffs. © 2022 Society of Chemical Industry.

Improved analysis of propamocarb and cymoxanil for the investigation of residue behavior in two vegetables with different cultivation conditions.

BACKGROUND: A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method was developed for the simultaneous determination of highly water-soluble propamocarb and hydrophobic cymoxanil in potato tuber and tomato fruit. Residue behaviors of the fungicides in open field or greenhouse were investigated for the safety evaluation of these two pesticides, and the effects of cultivation conditions, fungicide exposure and fruit size of tomato on residue level are discussed. RESULTS: Vegetable samples were extracted with ammonia-acetonitrile, further purified with multiwall carbon nanotubes and analyzed using high-performance liquid chromatography tandem mass spectrometry. The method was validated with fortified samples at different concentration levels (0.05-2.0 mg kg-1 ). Average recoveries ranged from 84 to 111% with relative standard deviations between 0.3 and 5.5%. Limits of quantification (LOQs) were set at the lowest spiking level of 0.05 mg kg-1 . In tomato and cherry tomato, initial residue level of cymoxanil was below LOQ at recommended good agricultural practices. Propamocarb residues were affected by the cultivation conditions, with highest levels of 0.52 and 0.72 mg kg-1 in open field and greenhouse, respectively. In addition, residues of propamocarb in cherry tomatoes were found to be present at 1.25 mg kg-1 . CONCLUSIONS: The field trial results showed that propamocarb and cymoxanil residues in potato tubers were below LOQ due to the tubers not being exposed to sprayed pesticides. The unexpected high residue levels in cherry tomato seem to indicate that cherry tomato with small size presents certain accumulative effects of propamocarb. © 2020 Society of Chemical Industry.

Meptyldinocap and azoxystrobin residue behaviors in different ecosystems under open field conditions and distribution on processed cucumber.

BACKGROUND: Several diseases and insects may cause damage to the normal growth of cucumber. Azoxystrobin and meptyldinocap, because of their novel mode of action, are effective against pathogens that have developed reduced sensitivity to other fungicides. Azoxystrobin is persistent in various crops and environments. However, there is a lack of research on the dissipation of these two pesticides, especially meptyldinocap. RESULTS: Analytes could be quantified with decent recoveries of 90-101%, with relative standard deviations (RSDs) of 3.0-10.1%. The terminal residues of meptyldinocap and azoxystrobin in cucumber were all < limit of quantification (LOQ) (0.02 and 0.05 mg kg-1 ). The half-lives of meptyldinocap and azoxystrobin were 0.8-1.1 and 1.2-2.8 days, respectively. The processing factors (PFs) for washing were all < 1, but the removal rate for washing was < 29.0%. Peeling had a significant effect on the removal of pesticide. The largest residue reductions were noticed through the pickling process, but special care should be taken regarding residues in the pickling solution as pesticides could transfer to them from cucumber. A more interesting finding was that the degradation of two pesticides was accelerated by the addition of calcium oxide. CONCLUSION: Pesticide residues on cucumber decreased after these processes. These results enable the health-risks from dietary exposures to pesticide residues to be characterized. They enable maximum residue limits (MRLs) to be established for pesticide residues in food products. They also assist the optimization of food processing with regard to pesticide residue dissipation. © 2019 Society of Chemical Industry.

Binary-solvent-based ionic-liquid-assisted surfactant-enhanced emulsification microextraction for the determination of four fungicides in apple juice and apple vinegar.

A binary-solvent-based ionic-liquid-assisted surfactant-enhanced emulsification microextraction method was developed for the separation/preconcentration and determination of four fungicides (pyrimethanil, fludioxonil, cyprodynil, pyraclostrobin) in apple juice and apple vinegar. A nonchlorinated solvent amyl acetate, which has a lower density than water, was used as the extraction solvent, and an ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate, which has a high density and low toxicity, was used as a secondary solvent mixed with the extraction solvent. After centrifugation, the binary solvent drop with a relatively high density was deposited on the bottom of the tube. Some parameters influencing the extraction efficiency of analytes such as type of extraction solvent, ratio of ionic liquid, volume of mixed solvent, type and concentration of surfactant, sample pH, NaCl concentration, and vortex time were investigated and optimized. Under the optimized conditions, the proposed method provided a good linearity in the range of 5-200 µg/L. The limits of quantification of the method were in the range of 2-5 µg/L. The relative standard deviations for interday assays were 1.7-11.9%. The method was applied to the determination of pyrimethanil, fludioxonil, cyprodynil, and pyraclostrobin in apple juice and apple vinegar samples, and the accuracy was evaluated through recovery experiments.

Ionic-liquid-based, manual-shaking- and ultrasound-assisted, surfactant-enhanced emulsification microextraction for the determination of three fungicide residues in juice samples.

A novel manual-shaking- and ultrasound-assisted surfactant-enhanced emulsification microextraction method was developed for the determination of three fungicides in juice samples. In this method, the ionic liquid, 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide, instead of a volatile organic solvent was used as the extraction solvent. The surfactant, NP-10, was used as an emulsifier to enhance the dispersion of the water-immiscible ionic liquid into an aqueous phase, which accelerated the mass transfer of the analytes. Organic dispersive solvent typically required in common dispersive liquid-liquid microextraction methods was not necessary. In addition, manual shaking for 15 s before ultrasound to preliminarily mix the extraction solvent and the aqueous sample could greatly shorten the time for dispersing the ionic liquid into aqueous solution by ultrasound irradiation. Several experimental parameters affecting the extraction efficiency, including type and volume of extraction solvent, type and concentration of surfactant, extraction time, and pH, were optimized. Under the optimized conditions, good linearity with the correlation coefficients (γ) higher than 0.9986 and high sensitivity with the limit of detection ranging from 0.4 to 1.6 µg/L were obtained. The average recoveries ranged from 61.4 to 86.0% for spiked juice, with relative standard deviations from 1.8 to 9.7%. The proposed method was demonstrated to be a simple, fast, and efficient method for the analysis of the target fungicides in juice samples.

Effervescence-assisted dispersive liquid-liquid microextraction using a solid effervescent agent as a novel dispersion technique for the analysis of fungicides in apple juice.

A novel effervescence-assisted dispersive liquid-liquid microextraction method has been developed for the determination of four fungicides in apple juice samples. In this method, a solid effervescent agent is added into samples to assist the dispersion of extraction solvent. The effervescent agent is environmentally friendly and only produces an increase in the ionic strength and a negligible variation in the pH value of the aqueous sample, which does not interfere with the extraction of the analytes. The parameters affecting the extraction efficiency were investigated including the composition of effervescent agent, effervescent agent amount, formulation of effervescent agent, adding mode of effervescent agent, type and volume of extraction solvent, and pH. Under optimized conditions, the method showed a good linearity within the range of 0.05-2 mg/L for pyrimethanil, fludioxonil, and cyprodinil, and 0.1-4 mg/L for kresoxim-methyl, with the correlation coefficients >0.998. The limits of detection for the method ranged between 0.005 and 0.01 mg/L. The recoveries of the target fungicides in apple juice samples were in the range of 72.4-110.8% with the relative standard deviations ranging from 1.2 to 6.8%.

Determination of strobilurin fungicides in cotton seed by combination of acetonitrile extraction and dispersive liquid-liquid microextraction coupled with gas chromatography.

The simultaneous determination of four strobilurin fungicides (picoxystrobin, kresoxim-methyl, trifloxystrobin, and azoxystrobin) in cotton seed by combining acetonitrile extraction and dispersive liquid-liquid microextraction was developed prior to GC with electron capture detection. Several factors, including the type and volume of the extraction and dispersive solvents, extraction condition and time, and salt addition, were optimized. The analytes were extracted with acetonitrile from cotton seed and the clean-up was carried out by primary secondary amine. Afterwards, 60 µL of n-hexane/toluene (1:1, v/v) with a lower density than water was mixed with 1 mL of the acetonitrile extract, then the mixture was injected into 7 mL of distilled water. A 0.1 mL pipette was used to collect a few microliters of n-hexane/toluene from the top of the aqueous solution. The enrichment factors of the analytes ranged from 36 to 67. The LODs were in the range of 0.1 × 10(-3) -2 × 10(-3) mg/kg. The relative recoveries varied from 87.7 to 95.2% with RSDs of 4.1-8.5% for the four fungicides. The good performance of the method, compared with the conventional pretreatments, has demonstrated it is suitable for determining low concentrations of strobilurin fungicide residues in cotton seed.

Smad inhibition by the Ste20 kinase Misshapen.

The level of TGF-ß/bone morphogenetic protein (BMP) signaling through Smad is tightly regulated to ensure proper embryonic patterning and homeostasis. Here we show that Smad activation by TGF-ß/BMP is blocked by a highly conserved phosphorylation event in the α-helix 1 region of Smad [T312 in Drosophila Smad1 (MAD)]. α-helix 1 phosphorylation reduces Smad interaction with TGF-ß/BMP receptor kinase and affects all receptor-activated Smads except Smad3. Tissue culture and transgenic studies in Drosophila further demonstrate that the biological activity of MAD is repressed by T312 phosphorylation in vivo. Through RNAi screening of the kinome, we have identified Misshapen (Msn) and the mammalian orthologs TNIK, MINK1, and MAP4K4 as the kinases responsible for α-helix 1 phosphorylation. Targeted expression of an active form of Msn in the wing imaginal disk disrupted activation of endogenous MAD by Dpp and expression of the Dpp/MAD target gene. Msn kinases belong to the Ste20 kinase family that has been shown to act as MAP kinase kinase kinase kinase (MAP4K). Our findings thus reveal a function of Msn independent of its impact on MAP kinase cascades. This Smad inhibition mechanism by Msn likely has important implications for development and disease.

Improved analysis of 230 pesticide residues in three fermented soy products by using automated one-step accelerated solvent extraction coupled with GC-MS/MS.

Consumer concerns over healthy diets are increasing as a result of the toxicity and persistence of pesticide residues in foodstuffs. Developing sensitive and high-throughput monitoring techniques for these trace residues is seen as an essential step in ensuring food safety. An automatic and sensitive multi-residue analytical method was developed and validated for the simultaneous determination of 230 compounds, including pesticides and their hazardous metabolites, in fermented soy products. The method included preparing the sample using on-line extraction and clean-up system based on accelerated solvent extraction (ASE), then determining the analytes using GC-MS/MS techniques. The homogenized samples (soy sauce, douchi, and sufu) were automatically extracted at 80 °C and 10.3 MPa and at the same time, in situ cleaned by 300 mg of primary secondary amine (PSA) combined with 20 mg of hydroxylated multi-walled carbon nanotubes in an extraction cell. The method obtained excellent calibration linearity (r > 0.9220) and a satisfactory analysis of the targeted compounds, which were evaluated with matrix-matched calibration standards over the range of 5-500 µg L-1. The limit of detections (LODs) of analytes were in the range of 0.01-1.29 µg kg-1, 0.01-1.39 µg kg-1, and 0.01-1.34 µg kg-1 in soy sauce, douchi, and sufu, respectively. The limit of quantifications (LOQs), which defined as the lowest spiking level, were set at 5.0 µg kg-1. The recoveries were within 70-120 % for over 95 % of the analytes, and the relative standard deviations (RSDs) were below 13.6 %. Moreover, a positive detection rate of 47 % were obtained when the proposed method was used on 15 real fermented soy products. These results suggested that the developed high-throughput method is highly feasible for monitoring of these target analytes in trace level.

Application of artificial hibernation technology in acute brain injury.

Controlling intracranial pressure, nerve cell regeneration, and microenvironment regulation are the key issues in reducing mortality and disability in acute brain injury. There is currently a lack of effective treatment methods. Hibernation has the characteristics of low temperature, low metabolism, and hibernation rhythm, as well as protective effects on the nervous, cardiovascular, and motor systems. Artificial hibernation technology is a new technology that can effectively treat acute brain injury by altering the body's metabolism, lowering the body's core temperature, and allowing the body to enter a state similar to hibernation. This review introduces artificial hibernation technology, including mild hypothermia treatment technology, central nervous system regulation technology, and artificial hibernation-inducer technology. Upon summarizing the relevant research on artificial hibernation technology in acute brain injury, the research results show that artificial hibernation technology has neuroprotective, anti-inflammatory, and oxidative stress-resistance effects, indicating that it has therapeutic significance in acute brain injury. Furthermore, artificial hibernation technology can alleviate the damage of ischemic stroke, traumatic brain injury, cerebral hemorrhage, cerebral infarction, and other diseases, providing new strategies for treating acute brain injury. However, artificial hibernation technology is currently in its infancy and has some complications, such as electrolyte imbalance and coagulation disorders, which limit its use. Further research is needed for its clinical application.

Lissencephaly-1 controls germline stem cell self-renewal through modulating bone morphogenetic protein signaling and niche adhesion.

In the Drosophila ovary, bone morphogenetic protein (BMP) signaling activated by the niche promotes germline stem cell (GSC) self-renewal and proliferation, whereas E-cadherin-mediated cell adhesion anchors GSCs in the niche for their continuous self-renewal. Here we show that Lissencephaly-1 (Lis1) regulates BMP signaling and E-cadherin-mediated adhesion between GSCs and their niche and thereby controls GSC self-renewal. Lis1 mutant GSCs are lost faster than control GSCs because of differentiation but not because of cell death, indicating that Lis1 controls GSC self-renewal. The Lis1 mutant GSCs exhibit reduced BMP signaling activity, and Lis1 interacts genetically with the BMP pathway components in the regulation of GSC maintenance. Mechanistically, Lis1 binds directly to and stabilizes the SMAD protein Mothers against decapentaplegic (Mad), facilitates its phosphorylation, and thereby regulates BMP signaling. Finally, the Lis1 mutant GSCs accumulate less E-cadherin in the stem cell-niche junction than do their wild-type counterparts. Germline-specific expression of an activated BMP receptor thickveins (Tkv) or E-cadherin can partially rescue the loss phenotype of Lis1 mutant GSCs. Therefore, this study has revealed a role of Lis1 in the control of Drosophila ovarian GSC self-renewal, at least partly by regulating niche signal transduction and niche adhesion. It has been known that Lis1 controls neural precursor/stem cell proliferation in the developing mammalian brain; this study further suggests that Lis1, which is widely expressed in adult mammalian tissues, could regulate adult tissue stem cells through modulating niche signaling and adhesion.

Application of the PDCA Cycle for Managing Hyperglycemia in Critically Ill Patients.

INTRODUCTION: Stress hyperglycemia is a common symptom in critically ill patients, and is not only a marker indicating the severity of illness but is also related to worsening outcomes. Managing stress hyperglycemia without increasing the likelihood of hypoglycemia is one of the most pressing challenges to be urgently addressed in clinics. The Plan-Do-Check-Act (PDCA) cycle management has been put forward in various surgical management scenarios, and has proven to be effective in the diagnosis and treatment of different diseases. It possesses dynamic characteristics and can be updated according to the results of glycemic control and feedback. This study focused on the use of PDCA to manage glucose levels in critically ill patients. METHODS: Based on the glucose level of 1003 critically ill patients admitted to the emergency intensive care unit (EICU) from 1 October 2019 to 31 December 2020, we collected and matched the prevalence of hyperglycemia, hypoglycemia, and glucose variability on a quarterly basis. According to the PDCA management method, we analyzed the possible causes, supervised the implementation of measures, summarized the feedback on improvements, and then proposed new improvement measures for implementation in the next quarter. RESULTS: Three measures were proposed and applied to enhance the management of hyperglycemia: (I) Updating and formulating three editions of the insulin infusion protocol and increasing the initial and maintenance doses of insulin on a case-by-case basis; (II) reducing the use of parenteral nutrition and ensuring that enteral nutrition is consumed at a uniform and slow rate; and (III) forming a training method during the COVID-19 pandemic and improving implementation of the insulin infusion protocol. Following PDCA management, the prevalence of hyperglycemia fell from 43.18% to 32.61%, the incidence of hypoglycemia was below 1.00%, and there was no significant fluctuation in blood glucose variability. CONCLUSION: The PDCA method is helpful in developing a superior insulin infusion protocol for critically ill patients and lowering the prevalence of hyperglycemia in critically ill patients.

Msk is required for nuclear import of TGF-{beta}/BMP-activated Smads.

Nuclear translocation of Smad proteins is a critical step in signal transduction of transforming growth factor beta (TGF-beta) and bone morphogenetic proteins (BMPs). Using nuclear accumulation of the Drosophila Smad Mothers against Decapentaplegic (Mad) as the readout, we carried out a whole-genome RNAi screening in Drosophila cells. The screen identified moleskin (msk) as important for the nuclear import of phosphorylated Mad. Genetic evidence in the developing eye imaginal discs also demonstrates the critical functions of msk in regulating phospho-Mad. Moreover, knockdown of importin 7 and 8 (Imp7 and 8), the mammalian orthologues of Msk, markedly impaired nuclear accumulation of Smad1 in response to BMP2 and of Smad2/3 in response to TGF-beta. Biochemical studies further suggest that Smads are novel nuclear import substrates of Imp7 and 8. We have thus identified new evolutionarily conserved proteins that are important in the signal transduction of TGF-beta and BMP into the nucleus.

Application of the PDCA Cycle for Managing Hyperglycemia in Critically Ill Patients.

Introduction: Stress hyperglycemia is a common symptom in critically ill patients, and is not only a marker indicating the severity of illness but is also related to worsening outcomes. Managing stress hyperglycemia without increasing the likelihood of hypoglycemia is one of the most pressing challenges to be urgently addressed in clinics. The Plan-Do-Check-Act (PDCA) cycle management has been put forward in various surgical management scenarios, and has proven to be effective in the diagnosis and treatment of different diseases. It possesses dynamic characteristics and can be updated according to the results of glycemic control and feedback. This study focused on the use of PDCA to manage glucose levels in critically ill patients. Methods: Based on the glucose level of 1003 critically ill patients admitted to the emergency intensive care unit (EICU) from 1 October 2019 to 31 December 2020, we collected and matched the prevalence of hyperglycemia, hypoglycemia, and glucose variability on a quarterly basis. According to the PDCA management method, we analyzed the possible causes, supervised the implementation of measures, summarized the feedback on improvements, and then proposed new improvement measures for implementation in the next quarter. Results: Three measures were proposed and applied to enhance the management of hyperglycemia: (I) Updating and formulating three editions of the insulin infusion protocol and increasing the initial and maintenance doses of insulin on a case-by-case basis; (II) reducing the use of parenteral nutrition and ensuring that enteral nutrition is consumed at a uniform and slow rate; and (III) forming a training method during the COVID-19 pandemic and improving implementation of the insulin infusion protocol. Following PDCA management, the prevalence of hyperglycemia fell from 43.18% to 32.61%, the incidence of hypoglycemia was below 1.00%, and there was no significant fluctuation in blood glucose variability. Conclusion: The PDCA method is helpful in developing a superior insulin infusion protocol for critically ill patients and lowering the prevalence of hyperglycemia in critically ill patients.

Inhibition of HMGB1 Might Enhance the Protective Effect of Taxifolin in Cardiomyocytes via PI3K/AKT Signaling Pathway.

Cardiovascular diseases (CVD) affect millions of people and spend a lot of medical costs around the world each year. Taxifolin is a natural anti-oxidative reagent obtained from multiple plants and exhibits a wide range of pharmacological effects. High mobility group box protein 1 (HMGB1) is expressed in multiple types of cells in the extracellular environment, regulating the pro-inflammatory process. Here, we detected the viability of cells using MTT assay, and the expression of each target protein was detected using western blotting analysis. The expression of each target mRNA was detected using the qPCR method, and the concentration of each cytokine in serum samples was detected using the ELISA method. In this study, we found that taxifolin could decrease the expression of hypoxia-inducible factor-1α (HIF-1α) while increasing the expression of endothelial nitric oxide synthase (eNOS), presented a protective role. Besides, taxifolin could also increase the expression of vascular endothelial growth factor-α (VEGF-α), transforming growth factor-ß (TGF-ß) and fibroblast growth factor21 (FGF21), resulting in viability rate increasing. And these effects were mediated by phosphatidylinositol 3-hydroxy kinase (PI3K)/AKT/mTOR signaling pathway; a similar trend was also observed in HMGB1 knockdown mice. We also found that inhibition of HMGB1 could enhance the cardioprotective effect of taxifolin and might be a new therapeutic strategy for cardiovascular disease.

Recyclable nitrogen-containing chitin-derived carbon microsphere as sorbent for neonicotinoid residues adsorption and analysis.

Chitin-derived three-dimensional nanomaterials has tremendous potential in pesticide residue analysis as an attractive green substitute for toxic solvents. The work presented herein focuses on constructing the environmentally friendly nitrogen-containing chitin-derived carbon microspheres (N-CCMP) for the efficient adsorption of neonicotinoid pesticides (NPs) including acetamiprid, clothianidin, imidacloprid and thiamethoxam. The N-CCMP displayed hierarchical porous structure, uniform size distribution, and excellent specific surface area of 680.8 m2 g-1. The N-CCMP with N-heterocyclic ring structure and surface oxygen functional groups exhibited good affinity to NPs, which was beneficial for the rapid adsorption. Then, the N-CCMP were utilized as sorbent in extraction of NP residues. Under the optimum conditions, the relative recoveries in water and juice sample were in the range of 85 %-116 % and 74 %-108 %, with relative standard deviations (RSDs) of 0.1 %∼5.2 % and 0.7 %∼5.2 %, respectively. The extraction performance of N-CCMP were still over 80 % after 5 times of reuse.

Residue Distribution, Dissipation Behavior, and Removal of Four Fungicide Residues on Harvested Apple after Waxing Treatment.

The residue distribution and dissipation of pyrimethanil, fludioxonil, cyprodinil, and kresoxim-methyl, which were introduced during postharvest waxing treatments of apples, were investigated. In addition, different residue removal methods were tested for the four fungicides in apples, and the removal efficiencies were compared. A multiresidue analytical method was developed based on quick, easy, cheap, effective, rugged, and safe method (QuEChERS) for the determination of the fungicide residues in apples. The dissipation study demonstrated that there was no significant change of fungicide residue magnitude during a 40-day storage process under ambient temperature. The fungicide residues in apples by wax treatment were shown to be very much stable. The results of residue distribution study demonstrated that waxing treatment may help to reduce the risk of pesticide when only the pulp was consumed. In the residue removal study, results suggested that higher temperature and the addition of acetic acid can improve the residue removal efficiency.

Removal of nine pesticide residues from water and soil by biosorption coupled with degradation on biosorbent immobilized laccase.

Biosorbents prepared with peanut shell and wheat straw were act as supports for the immobilization of Aspergillus laccase, and the redox mediator syringaldehyde (SA) was used to improve laccase-catalyzed degradation of nine pesticide residues, including isoproturon, atrazine, prometryn, mefenacet, penoxsulam, nitenpyram, prochloraz, pyrazosulfuron-ethyl and bensulfuron-methyl. Pesticides in water and soil samples were effectively removed via biosorbent concentration and subsequent immobilized laccase degradation on peanut shell or wheat straw supports. The Langmuir equation and Freundlich equation described the biosorption isotherms of the nine pesticides. Parameters that affect the degradation was also investigated. With concentration of pesticides and SA of 6.0 mg L-1 and 1 mmol L-1, over 54.5% and 65.9% of pesticides were removed in water in 3 days with a biosorbent immobilized laccase dose of 25 g L-1 for peanut shell immobilized laccase and wheat straw immobilized laccase, respectively. In the treatment of pesticide in soil with a biosorbent dose of 50 g (kg soil)-1, with the maximum degradation rates ranged from 20.9 to 92.9% and 14.7-92.0% in 7 days for peanut shell immobilized laccase and wheat straw immobilized laccase, respectively. Therefore, laccase immobilized on biomass materials has a strong potential for the effective removal of pesticide pollutants from water and soil by biosorption coupled with degradation.

Ionic liquid-based air-assisted liquid-liquid microextraction followed by high performance liquid chromatography for the determination of five fungicides in juice samples.

A novel and simple ionic liquid-based air-assisted liquid-liquid microextraction technique combined with high performance liquid chromatography was developed to analyze five fungicides in juice samples. In this method, ionic liquid was used instead of a volatile organic solvent as the extraction solvent. The emulsion was formed by pulling in and pushing out the mixture of aqueous sample solution and extraction solvent repeatedly using a 10mL glass syringe. No organic dispersive solvent was required. Under the optimized conditions, the limits of detection (LODs) were 0.4-1.8µgL-1 at a signal-to-noise ratio of 3. The limits of quantification (LOQs) set as the lowest spiking levels with acceptable recovery in juices were 10µgL-1, except for fludioxonil whose LOQ was 20µgL-1. The proposed method was applied to determine the target fungicides in juice samples, and acceptable recoveries ranging from 74.9% to 115.4% were achieved.