Correction: Development of an enhanced analytical method utilizing pepper matrix as an analyte protectant for sensitive GC‒MS/MS detection of dimethipin in animal-based food products.

[This corrects the article DOI: 10.1371/journal.pone.0295968.].

Development of an enhanced analytical method utilizing pepper matrix as an analyte protectant for sensitive GC‒MS/MS detection of dimethipin in animal-based food products.

Herein, an analytical method using gas chromatography-tandem mass spectrometry (GC‒MS/MS) was devised to detect the presence of the troublesome pesticide dimethipin in various animal-based food products, including chicken, pork, beef, eggs, and milk. The injection port was primed with a matrix derived from pepper leaves that acts as an analyte protectant (AP) to safeguard the target compound from thermal degradation during gas chromatography. The presence of AP resulted in a remarkable limit of quantification of 0.005 mg/kg for dimethipin in five matrices. Three different versions (original, EN, and AOAC) of the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method were compared for dimethipin extraction, with a double-layer solid-phase extraction (SPE) cartridge utilized for matrix purification. A seven-point external calibration curve was established for dimethipin in the five matrices, demonstrating excellent linearity with determination coefficients (R2) ≥ 0.998. The developed quantitative method was validated by fortifying each matrix with three different concentrations of standard dimethipin, and the average recovery fell within the acceptable range outlined in the CODEX guidelines (ranging from 88.8% to 110.0%), with a relative standard deviation (RSD) of ≤ 11.97%. This method effectively addresses the challenge of analyzing dimethipin and can therefore be used as a routine monitoring tool for dimethipin across various matrices.

Slc9a1 plays a vital role in chitosan oligosaccharide transport across the intestinal mucosa of mice.

The mechanism underlying the intestinal transport of COS is not well understood. Here, transcriptome and proteome analyses were performed to identify potential critical molecules involved in COS transport. Enrichment analyses revealed that the differentially expressed genes in the duodenum of the COS-treated mice were mainly enriched in transmembrane and immune function. In particular, B2 m, Itgb2, and Slc9a1 were upregulated. The Slc9a1 inhibitor decreased the transport efficiency of COS both in MODE-K cells (in vitro) and in mice (in vivo). The transport of FITC-COS in Slc9a1-overexpressing MODE-K cells was significantly higher than that in empty vector-transfected cells (P < 0.01). Molecular docking analysis revealed the possibility of stable binding between COS and Slc9a1 through hydrogen bonding. This finding indicates that Slc9a1 plays a crucial role in COS transport in mice. This provides valuable insights for improving the absorption efficiency of COS as a drug adjuvant.

A Comprehensive Review of Pesticide Residues in Peppers.

Pesticides are chemicals that are used to control pests such as insects, fungi, and weeds. Pesticide residues can remain on crops after application. Peppers are popular and versatile foods that are valued for their flavor, nutrition, and medicinal properties. The consumption of raw or fresh peppers (bell and chili) can have important health benefits due to their high levels of vitamins, minerals, and antioxidants. Therefore, it is crucial to consider factors such as pesticide use and preparation methods to fully realize these benefits. Ensuring that the levels of pesticide residues in peppers are not harmful to human health requires rigorous and continuous monitoring. Several analytical methods, such as gas chromatography (GC), liquid chromatography (LC), mass spectrometry (MS), infrared spectroscopy (IR), ultraviolet-visible spectroscopy (UV-Vis), and nuclear magnetic resonance spectroscopy (NMR), can detect and quantify pesticide residues in peppers. The choice of analytical method depends on the specific pesticide, that is being tested for and the type of sample being analyzed. The sample preparation method usually involves several processes. This includes extraction, which is used to separate the pesticides from the pepper matrix, and cleanup, which removes any interfering substances that could affect the accuracy of the analysis. Regulatory agencies or food safety organizations typically monitor pesticide residues in peppers by stipulating maximum residue limits (MRLs). Herein, we discuss various sample preparation, cleanup, and analytical techniques, as well as the dissipation patterns and application of monitoring strategies for analyzing pesticides in peppers to help safeguard against potential human health risks. From the authors' perspective, several challenges and limitations exist in the analytical approach to monitoring pesticide residues in peppers. These include the complexity of the matrix, the limited sensitivity of some analytical methods, cost and time, a lack of standard methods, and limited sample size. Furthermore, developing new analytical methods, using machine learning and artificial intelligence, promoting sustainable and organic growing practices, improving sample preparation methods, and increasing standardization could assist efficiently in analyzing pesticide residues in peppers.

Competitive fluorescent immunosensor based on catalytic hairpin self-assembly for multiresidue detection of organophosphate pesticides in agricultural products.

Simple and rapid multiresidue trace detection of organophosphate pesticides (OPs) is extremely important for various reasons, including food safety, environmental monitoring, and national health. Here, a catalytic hairpin self-assembly (CHA)-based competitive fluorescent immunosensor was developed to detect OPs in agricultural products, involving enabled dual signal amplification followed by a CHA reaction. The developed method could detect 0.01-50 ng/mL triazophos, parathion, and chlorpyrifos, with limits of detection (LODs) of 0.012, 0.0057, and 0.0074 ng/mL, respectively. The spiked recoveries of samples measured using this assay ranged from 82.8 % to 110.6 %, with CV values ranging between 5.5 % and 18.5 %. This finding suggests that the CHA-based competitive fluorescent immunosensor is a reliable and accurate method for detecting OPs in agricultural products. The results correlated well with those obtained from the liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, indicating that the CHA-based biosensor is able to accurately detect OPs and can be used as a reliable alternative to the LC-MS/MS method. Additionally, the CHA-based biosensor is simpler and faster than LC-MS/MS, which makes it a more practical and cost-effective option for the detection of OPs. In summary, the CHA-based competitive fluorescent immunosensor can be considered a promising approach for trace analysis and multiresidue determination of pesticides, which can open up new horizons in the fields of food safety, environmental monitoring, and national health.

Recent Advances in Rapid Detection Techniques for Pesticide Residue: A Review.

As an important chemical pollutant affecting the safety of agricultural products, the on-site and efficient detection of pesticide residues has become a global trend and hotspot in research. These methodologies were developed for simplicity, high sensitivity, and multiresidue detection. This review introduces the currently available technologies based on electrochemistry, optical analysis, biotechnology, and some innovative and novel technologies for the rapid detection of pesticide residues, focusing on the characteristics, research status, and application of the most innovative and novel technologies in the past 10 years, and analyzes challenges and future development prospects. The current review could be a good reference for researchers to choose the appropriate research direction in pesticide residue detection.

Microencapsulation of Plant Phenolic Extracts Using Complex Coacervation Incorporated in Ultrafiltered Cheese Against AlCl3-Induced Neuroinflammation in Rats.

Plant-derived phenolic compounds have numerous biological effects, including antioxidant, anti-inflammatory, and neuroprotective effects. However, their application is limited because they are degraded under environmental conditions. The aim of this study was to microencapsulate plant phenolic extracts using a complex coacervation method to mitigate this problem. Red beet (RB), broccoli (BR), and spinach leaf (SL) phenolic extracts were encapsulated by complex coacervation. The characteristics of complex coacervates [zeta potential, encapsulation efficiency (EE), FTIR, and morphology] were evaluated. The RB, BR, and SL complex coacervates were incorporated into an ultrafiltered (UF) cheese system. The chemical properties, pH, texture profile, microstructure, and sensory properties of UF cheese with coacervates were determined. In total, 54 male Sprague-Dawley rats were used, among which 48 rats were administered an oral dose of AlCl3 (100 mg/kg body weight/d). Nutritional and biochemical parameters, including malondialdehyde, superoxide dismutase, catalase, reduced glutathione, nitric oxide, acetylcholinesterase, butyrylcholinesterase, dopamine, 5-hydroxytryptamine, brain-derived neurotrophic factor, and glial fibrillary acidic protein, were assessed. The RB, BR, and SL phenolic extracts were successfully encapsulated. The RB, BR, and SL complex coacervates had no impact on the chemical composition of UF cheese. The structure of the RB, BR, and SL complex coacervates in UF cheese was the most stable. The hardness of UF cheese was progressively enhanced by using the RB, BR, and SL complex coacervates. The sensory characteristics of the UF cheese samples achieved good scores and were viable for inclusion in food systems. Additionally, these microcapsules improved metabolic strategies and neurobehavioral systems and enhanced the protein biosynthesis of rat brains. Both forms failed to induce any severe side effects in any experimental group. It can be concluded that the microencapsulation of plant phenolic extracts using a complex coacervation technique protected rats against AlCl3-induced neuroinflammation. This finding might be of interest to food producers and researchers aiming to deliver natural bioactive compounds in the most acceptable manner (i.e., food).

Design and Characterization of a Novel Hapten and Preparation of Monoclonal Antibody for Detecting Atrazine.

This study provides the first design and synthetic protocol for preparing highly sensitive and specific atrazine (ATR) monoclonal antibodies (mAbs). In this work, a previously unreported hapten, 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine, was designed and synthesized, which maximally exposed the characteristic amino group ATR to an animal immune system to induce the expected antibody. The molecular weight of the ATR hapten was 259.69 Da, and its purity was 97.8%. The properties of the anti-ATR mAb were systematically characterized. One 9F5 mAb, which can detect ATR, was obtained with an IC50 value (the concentration of analyte that produced 50% inhibition of ATR) of 1.678 µg/L for ATR. The molecular weight for the purified 9F5 mAb was approximately 52 kDa for the heavy chain and 15 kDa for the light chain. The anti-ATR mAb prepared in this study was the IgG1 type. The working range of the standard curve (IC20 (the concentration of analyte that produced 20% inhibition of ATR)-IC80 (the concentration of analyte that produced 80% inhibition of ATR)) was 0.384 to 11.565 µg/L. The prepared anti-ATR mAb had high specificity, sensitivity, and affinity with low cross-reactivity. The prepared anti-ATR mAb could provide the core raw material for establishing an ATR immunoassay.

Simultaneous Determination of Pyridate, Quizalofop-ethyl, and Cyhalofop-butyl Residues in Agricultural Products Using Liquid Chromatography-Tandem Mass Spectrometry.

An analytical method was developed to simultaneously determine pyridate, quizalofop-ethyl, and cyhalofop-butyl in brown rice, soybean, potato, pepper, and mandarin using LC-MS/MS. Purification was optimized using various sorbents: primary−secondary amine, octadecyl (C18) silica gel, graphitized carbon black, zirconium dioxide-modified silica particles, zirconium dioxide-modified silica particles (Z-SEP), and multi-walled carbon nanotubes (MWCNTs). Three versions of QuECHERS methods were then tested using the optimal purification agent. Finally, samples were extracted using acetonitrile and QuEChERS EN salts and purified using the Z-SEP sorbent. A six-point matrix-matched external calibration curve was constructed for the analytes. Good linearity was achieved with a determination coefficient ≥0.999. The limits of detection and quantification were 0.0075 mg/kg and 0.01 mg/kg, respectively. The method was validated after fortifying the target standards to the blank matrices at three concentration levels with five replicates for each concentration. The average recovery was within an acceptable range (70−120%), with a relative standard deviation <20%. The applicability of the developed method was evaluated with real-world market samples, all of which tested negative for these three herbicide residues. Therefore, this method can be used for the routine analysis of pyridate, quizalofop-ethyl, and cyhalofop-butyl in agricultural products.

A Review on Extraction, Characterization, and Applications of Bioactive Peptides From Pressed Black Cumin Seed Cake.

Plenty of black cumin cake was generated as a natural waste material after pressing the oil. Nigella sativa (black cumin) seeds and cakes are of precious nutritional value as they contain proteins, phenolics, essential amino acids, and bioactive compounds. Owing to their antioxidant properties, scientists and food manufacturers have extensively developed them. Notably, global awareness among consumers about the benefits of innovative food ingredients has been increased. Meanwhile, it has to be noted that vast amounts of cake by-products are not effectively utilized, which might cause economic loss and environmental consequences. This review aimed to highlight the antioxidant abilities, extraction, characterization, functional characteristics, and utilization of active peptides acquired from black seed oil cake. This overview would critically evaluate black seed cake proteins, plentiful in bioactive peptides that might be utilized as valuable additives in feed, food, pharmaceutical, and cosmetic industries. The addition of bioactive peptides to restrain the oxidation of fat-based products and preserve food safety is also addressed.

Development of an analytical method for multi-residue quantification of 18 anthelmintics in various animal-based food products using liquid chromatography-tandem mass spectrometry.

In this study, we developed a simple screening procedure for the determination of 18 anthelmintics (including benzimidazoles, macrocyclic lactones, salicylanilides, substituted phenols, tetrahydropyrimidines, and imidazothiazoles) in five animal-derived food matrices (chicken muscle, pork, beef, milk, and egg) using liquid chromatography-tandem mass spectrometry. Analytes were extracted using acetonitrile/1% acetic acid (milk and egg) and acetonitrile/1% acetic acid with 0.5 mL of distilled water (chicken muscle, pork, and beef), and purified using saturated n-hexane/acetonitrile. A reversed-phase analytical column and a mobile phase consisting of (A) 10 mM ammonium formate in distilled water and (B) methanol were used to achieve optimal chromatographic separation. Matrix-matched standard calibration curves (R 2 ≥0.9752) were obtained for concentration equivalent to ×1/2, ×1, ×2, ×3, ×4, and ×5 fold the maximum residue limit (MRL) stipulated by the Korean Ministry of Food and Drug Safety. Recoveries of 61.2-118.4%, with relative standard deviations (RSDs) of ≤19.9% (intraday and interday), were obtained for each sample at three spiking concentrations (×1/2, ×1, and ×2 the MRL values). Limits of detection, limits of quantification, and matrix effects were 0.02-5.5 µg/kg, 0.06-10 µg/kg, and -98.8 to 13.9% (at 20 µg/kg), respectively. In five samples of each food matrix (chicken muscle, pork, beef, milk, and egg) purchased from large retailers in Seoul that were tested, none of the target analytes were detected. It has therefore been shown that this protocol is adaptable, accurate, and precise for the quantification of anthelmintic residues in foods of animal origin.

Onsite/on-field analysis of pesticide and veterinary drug residues by a state-of-art technology: A review.

Pesticides and veterinary drugs are generally employed to control pests and insects in crop and livestock farming. However, remaining residues are considered potentially hazardous to human health and the environment. Therefore, regular monitoring is required for assessing and legislation of pesticides and veterinary drugs. Various approaches to determining residues in various agricultural and animal food products have been reported. Most analytical methods involve sample extraction, purification (cleanup), and detection. Traditional sample preparation is time-consuming labor-intensive, expensive, and requires a large amount of toxic organic solvent, along with high probability for the decomposition of a compound before the analysis. Thus, modern sample preparation techniques, such as the quick, easy, cheap, effective, rugged, and safe method, have been widely accepted in the scientific community for its versatile application; however, it still requires a laboratory setup for the extraction and purification processes, which also involves the utilization of a toxic solvent. Therefore, it is crucial to elucidate recent technologies that are simple, portable, green, quick, and cost-effective for onsite and infield residue detections. Several technologies, such as surface-enhanced Raman spectroscopy, quantum dots, biosensing, and miniaturized gas chromatography, are now available. Further, several onsite techniques, such as ion mobility-mass spectrometry, are now being upgraded; some of them, although unable to analyze field sample directly, can analyze a large number of compounds within very short time (such as time-of-flight and Orbitrap mass spectrometry). Thus, to stay updated with scientific advances and analyze organic contaminants effectively and safely, it is necessary to study all of the state-of-art technology.

Simultaneous quantification of 12 veterinary drug residues in fishery products using liquid chromatography-tandem mass spectrometry.

Herein, an analytical method was developed for simultaneous determination of 12 anthelmintics (closantel, niclosamide, nitroxynil, rafoxanide, cymiazole, fluazuron, levamisole, morantel, praziquantel, pyrantel, thiophanate, and trichlorfon) in fishery products (eel, flatfish, and shrimp) using liquid-liquid extraction coupled with liquid chromatography-tandem mass spectrometry. A reversed-phase analytical column was then used to separate the analytes from various matrices. Linear matrix-matched calibration curves were generated with coefficients of determination ≥ 0.9935. Recovery rates at three spiking levels (5, 10, and 20 µg/kg) ranged between 61.58% and 119.37% with relative standard deviations ≤ 19.05%. Limits of detection were in the range of 0.3-1.6 µg/kg, whereas limits of quantification ranged between 1.0 and 5.0 µg/kg. The matrix effect was moderate with values ranging from -99.47% to 51.98%. Matrices procured from large markets tested negative for the 12 anthelmintics. The developed method proved amenable to real sample testing and can be used for simultaneous determination of target analytes in aquatic products.

Simultaneous Quantification of Chloramphenicol, Thiamphenicol, Florfenicol, and Florfenicol Amine in Animal and Aquaculture Products Using Liquid Chromatography-Tandem Mass Spectrometry.

The accumulation of antimicrobial residues in edible animal products and aquaculture products could pose health concerns to unsuspecting consumers. Hence, this study aimed to develop a validated method for simultaneous quantification of chloramphenicol (CAP), thiamphenicol (TAP), florfenicol (FF), and florfenicol amine (FFA) in beef, pork, chicken, shrimp, eel, and flatfish using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Primary-secondary amine (PSA) and MgSO4 were used for sample purification. The analytes were separated on a reversed-phase analytical column. The coefficients of determination for the linear matrix-matched calibration curves were ≥0.9941. Recovery rates ranged between 64.26 and 116.51% for the four analytes with relative standard deviations (RSDs) ≤ 18.05%. The calculated limits of detection (LODs) and limits of quantification (LOQs) were 0.005-3.1 and 0.02-10.4 µg/kg, respectively. The developed method was successfully applied for monitoring samples obtained from local markets in Seoul, Republic of Korea. The target residues were not detected in any tested matrix. The designed method was versatile, sensitive, and proved suitable for quantifying residues in animal-derived products.

Bioactivities, Applications, Safety, and Health Benefits of Bioactive Peptides From Food and By-Products: A Review.

Bioactive peptides generated from food proteins have great potential as functional foods and nutraceuticals. Bioactive peptides possess several significant functions, such as antioxidative, anti-inflammatory, anticancer, antimicrobial, immunomodulatory, and antihypertensive effects in the living body. In recent years, numerous reports have been published describing bioactive peptides/hydrolysates produced from various food sources. Herein, we reviewed the bioactive peptides or protein hydrolysates found in the plant, animal, marine, and dairy products, as well as their by-products. This review also emphasizes the health benefits, bioactivities, and utilization of active peptides obtained from the mentioned sources. Their possible application in functional product development, feed, wound healing, pharmaceutical and cosmetic industries, and their use as food additives have all been investigated alongside considerations on their safety.

Quantification of spinosyn A and spinosyn D in animal-derived products using multiwalled carbon nanotubes coupled with LC-MS/MS for analysis.

An analytical method was developed for the quantification of spinosad (sum of spinosyns A and D) in five animal-derived products (chicken breast, pork, beef, egg, and milk) using LC-MS/MS. The sample was extracted using acetonitrile/1% acetic acid and a combination of magnesium sulfate and sodium acetate salts. The sample was purified using multiwalled carbon nanotubes as sorbent via a dispersive-solid-phase extraction procedure. Matrix-matched calibration (seven-point) provided good linearity with coefficient of determination (R2 ) ≥0.99 for each product. The limits of detection and quantification (LOQs) ranged between 0.0003-0.03 and 0.001-0.1 mg/kg, respectively. Method validation was carried out after spiking the target standard to blank matrices at the concentration levels of LOQ, 2 × LOQ, and 10 × LOQ with three replicates for each. The average recoveries were between 74 and 104%, with relative standard deviations ≤9.68, which were within the acceptable range designated by the international organizations. The developed method was successfully applied for monitoring market samples collected throughout the Korean Peninsula, and none of the samples tested positive for the target analytes. It has therefore been shown that dehydration and acidification were effective to extract spinosad from animal-derived products.

Establishment of import tolerance for the insecticide thiacloprid in strawberry.

To promote exports, import tolerance (IT) of thiacloprid in strawberry was proposed using the Organization for Economic Cooperation and Development (OECD) maximum residue limit (MRL) calculator after conducting three different field trials. The pre-harvest interval of residual pattern and degradation dynamics of thiacloprid in strawberry were determined using ultra-performance liquid chromatography-tandem mass spectrometry. Samples were extracted with acetonitrile and a mixture of salts and dilution was performed for purification. A six-point matrix-matched calibration curve was constructed which provided excellent linearity with coefficient of determination (R2 ) of 0.9998 or more. Detection and quantification limits were 0.003 and 0.01 mg/kg, respectively. The method was validated in quintuplicate at three different concentrations, which resulted in acceptable recovery ranging from 80.86% to 101.71% with relative standard deviation of 6.50 or less among the three field sites. The developed method was applied to the field-treated sample harvested at different intervals. In the pre-harvest interval trial, the amount of thiacloprid residues ranged from 0.24 to 0.70 mg/kg in field site 1 (Nonsan), 0.16 to 0.50 mg/kg in field site 2 (Sunchang), and 0.36 to 0.50 mg/kg in field site 3 (Sacheon). By contrast, in the degradation trial, the observed residues were 0.03-0.81 mg/kg in field site 1 and 0.02-0.48 mg/kg in field site 2. Consequently, the IT of thiacloprid in strawberry using the OECD MRL calculator was proposed as 2 mg/kg, which is exactly the same as the MRL established by the Republic of Korea. In conclusion, the residue study proposes 2.0 mg/kg as the MRL of thiacloprid in strawberries.

Development of an analytical method for multi-residue quantification of 18 anthelmintics in various animal-based food products using liquid chromatography-tandem mass spectrometry / 药物分析学报

In this study,we developed a simple screening procedure for the determination of 18 anthelmintics(including benzimidazoles,macrocyclic lactones,salicylanilides,substituted phenols,tetrahydropyr-imidines,and imidazothiazoles)in five animal-derived food matrices(chicken muscle,pork,beef,milk,and egg)using liquid chromatography-tandem mass spectrometry.Analytes were extracted using acetonitrile/1％acetic acid(milk and egg)and acetonitrile/1％acetic acid with 0.5 mL of distilled water(chicken muscle,pork,and beef),and purified using saturated n-hexane/acetonitrile.A reversed-phase analytical column and a mobile phase consisting of(A)10 mM ammonium formate in distilled water and(B)methanol were used to achieve optimal chromatographic separation.Matrix-matched standard calibration curves(R2≥0.9752)were obtained for concentration equivalent to ×1/2,×1,×2,×3,×4,and ×5 fold the maximum residue limit(MRL)stipulated by the Korean Ministry of Food and Drug Safety.Recoveries of 61.2-118.4％,with relative standard deviations(RSDs)of ≤19.9％(intraday and interday),were obtained for each sample at three spiking concentrations(×1/2,×1,and ×2 the MRL values).Limits of detection,limits of quantification,and matrix effects were 0.02-5.5 μg/kg,0.06-10 μg/kg,and-98.8 to 13.9％(at 20 μg/kg),respectively.In five samples of each food matrix(chicken muscle,pork,beef,milk,and egg)purchased from large retailers in Seoul that were tested,none of the target analytes were detected.It has therefore been shown that this protocol is adaptable,accurate,and precise for the quantification of anthelmintic residues in foods of animal origin.

Administration of kynurenic acid reduces hyperlipidemia-induced inflammation and insulin resistance in skeletal muscle and adipocytes.

Kynurenic acid (KA), an endogenous product of L-tryptophan metabolism in the kynurenine pathway, regulates adipose tissue energy homeostasis and inflammation. However, its role in palmitate-induced insulin resistance and detailed underlying mechanisms in skeletal muscles and adipose tissues are unclear. Herein, we report that KA ameliorated palmitate-induced inflammation and insulin resistance in differentiated C2C12 and 3T3-L1 cell lines as well as soleus skeletal muscle and subcutaneous adipose tissues in mice. Palmitate-induced inflammatory markers, such as nuclear factor κB translocation, inhibitory κBα phosphorylation, pro-inflammatory cytokine expression, and impaired insulin signaling, were markedly attenuated by KA both in vitro and in vivo. KA significantly increased AMP-activated protein kinase (AMPK) phosphorylation and sirtuin 6 (SIRT6) expressions in C2C12 myocytes and 3T3-L1 adipocytes and skeletal muscle and adipose tissues of mice. siRNA-mediated AMPK or SIRT6 inhibition significantly mitigated the suppressive effects of KA on palmitate-induced inflammation and insulin resistance. KA significantly stimulated expression of genes involved in fatty acid oxidation in C2C12 myocytes and skeletal muscle of mice. Moreover, KA inhibits lipogenesis in 3T3-L1 adipocytes. AMPK or SIRT6 siRNA markedly reversed these changes. The siRNA targeting Gpr35 abrogated the effects of KA on AMPK phosphorylation in C2C12 myocytes and 3T3-L1 adipocytes, except SIRT6 expression. It has therefore been shown that KA could potentially alleviate inflammation and insulin resistance in skeletal muscle and adipose tissues through Gpr35/AMPK and SIRT6-mediated pathways.

Upgrading analytical methodology through comparative study for screening of 267 pesticides/metabolites in five representative matrices using UPLC-MS/MS.

A comparative study was conducted to replace the traditional screening method (MFDS#83) with the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) EN method for the determination of 267 pesticides/metabolites/plant activators/growth regulators in five representative crop matrices (mandarin, pepper, potato, rice, and soybean). In the traditional method, samples were extracted with acetonitrile and salt, and purified with a solid-phase extraction cartridge. In the QuEChERS method, the sample extraction was carried out using acetonitrile and a mixture of salts, and purification was performed using dispersive solid phase extraction. The limit of quantification (LOQ) for the MFDS#83 method was 0.0004 mg/kg, whereas for the QuEChERS EN method, the LOQ varied from 0.002 to 0.006 mg/kg for all analytes in various matrices. A six-point matrix-matched calibration curve was prepared for all analytes in five matrices for both methods. Both the MFDS#83 and QuEChERS EN methods provided excellent linearity, with the coefficients of determination (R2) ≥ 0.99 for most of the compounds. In both cases, the method was validated in terms of recovery and repeatability after the fortification of two different concentrations with three replicates for each of the concentrations. The QuEChERS EN method provided better recovery than the MFDS#83 method for all matrices except mandarin.