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Objective: An ultra-high liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-QTOF-MS) was established and applied for the screening and quantitation of pesticide residues in raw milk and infant and young children formula milk powder. Methods: A stable and reliable pretreatment procedure involving quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction and Captiva EMR-lipid cleanup was developed and validated. The samples were separated on a Luna Omega Polar C18 (2.1 mm × 100 mm, 1.6 μm) by gradient elution using mobile phase A consisting of 2 mmol/L ammonium formate and 0.01% formic acid and mobile phase B consisting of 2 mmol/L ammonium formate and 0.01% formic acid. By analyzing commercial pesticide certified reference materials, a single injection method using two fragmentation techniques, collision-induced dissociation (CID) and electron activated dissociation (EAD) was developed for the simultaneous qualitative screening and quantitative analysis of 500 pesticide compounds, in which mass spectrometry data were collected using the Zeno sequential window acquisition of all theoretical fragment ion spectra (SWATH) data-independent acquisition (DIA) mode. Comprehensive scores obtained by the OS software from four factors, including mass deviation, retention time deviation, differential isotope ratio and spectrum library similarity, were used for qualitative screening. The matrix-matched external standard method was used for quantitative analysis based on the peak area of precursor ions in the extracted ion chromatogram (XIC). Results: The comprehensive scores of the 500 pesticides and their metabolites ranged from 90.4 to 99.4 points, higher than the minimum score of qualitative screening (90 points), and the limits of detection (LOD) were in the range of 0.025–0.5 μg/kg. The correlation coefficients (r2) of the matrix-matched calibration curves for 103 pesticides and their metabolites with maximum residue limits (MRL) in milk set by the national standard of China GB 2763-2021 were above 0.99. The average recoveries ranged from 72.7% to 114.5% at three spiked concentration levels with relative standard deviations (RSDs) of 2.1%–13.6% (n = 6), and the limits of quantitation (LOQ) were in the range of 0.15–3 μg/kg. Conclusion: This method was sensitive and accurate, and could be used for the screening identification of multiple pesticides and their metabolites and the quantitative analysis of restricted pesticides with high detection rate in raw milk and infant formula milk powder at low cost.

ObjectiveA method was developed for the rapid determination of 18 common disinfection by-products including halogenated oxides and haloacetic acid （HAAs） in drinking water by high performance liquid chromatography tandem mass spectrometry （HPLC-MS/MS）.MethodThe water sample was filtered by 0.22 μm hydrophilic membrane then the analytes were separated on a PFP （2.1 mm× 100 mm， 2.7 μm） pentafluorophenyl column with 0.1% acetic acid and acetonitrile as mobile phase gradient elution. Ionization in anionic electrospray mode was detected by multi-reaction monitoring （MRM） mode. The external standard method was used for quantitation.ResultsThe correlation coefficients of 18 disinfection by-products were above 0.999 in the corresponding linear range. The average spiked recoveries of 1， 10 and 20 times of LOQ of each analyte were 91.6%‒101.8%， and the relative standard deviation （RSD） was 1.2%‒6.4%. The LOD and LOQ were 0.020‒2 μg·L-1 and 0.050‒5 μg·L-1， respectively.ConclusionThis method is simple， sensitive and accurate， and could be used for the routine analysis of 18 common disinfection by-products in drinking water.

ObjectiveTo verify the main quality indexes of coenzyme Q10， and study the quality consistency of coenzyme Q10 produced by different processes.MethodsAccording to the Chinese Pharmacopoeia （2020 version） and national food safety standards， the main quality indexes such as coenzyme Q10 components， moisture， related substances， isomers， contaminant residues and microbial indexes of 40 batches of raw materials were detected.ResultsThe content of coenzyme Q10 in all collected materials was above 99.2%； the maximum single impurity ranged from 0.27% to 0.37%； the total impurity ranged from 0.45% to 0.85%. The total number of colonies in all samples was less than 10 CFU/g， Escherichia coli， Staphylococcus aureus and Salmonella were not detected， and the total number of yeasts and molds were less than 10 CFU/g. The results of moisture and contaminant residues all met the requirements.ConclusionAll coenzyme Q10 collected as health food raw materials met the requirements of Chinese Pharmacopoeia （2020 version） and GB 16740-2014 National Food Safety Standard Health Food.

The aim of individuals consuming health supplements is to attain a robust state through nutritional regulation. However, some unscrupulous manufacturers, motivated by profit, fraudulently incorporate drugs or unauthorized components with therapeutic effects into the product for instant product performance enhancement. The long-term use of these products may inadvertently inflict harm on human health and fail to promote nutritive healthcare. The illegal inclusion of these substances is prevalent in kidney-tonifying and sexuality-enhancing products. Developing effective analytical methods to identify these products and screen for illegal added ingredients can effectively prevent such products from reaching and remaining on the market. A target screening method for the detection and quantification of 90 phosphodiesterase type 5 inhibitors (PDE-5is) in 5 kinds of health products was developed and validated. The type of dietary supplements varied from tablets, capsules, and protein powder to wine and beverages. Sample preparation was completed with a one-step liquid phase extraction. The screening process of 90 PDE-5is was done efficiently within 25 min by ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) using the dynamic multiple reaction monitoring (dMRM) technique. The LODs of 90 PDE-5is were detected at levels ranging from 25 to 85 ng/g or ng/mL. This novel targeting methodology was effective and can be applied to routine market supervision. Among 286 batches of samples, 8 batches were found to be positive. Three kinds of PDE-5is were first detected in healthy products. The screening method demonstrated herein will be a promising and powerful tool for rapid screening of PDE-5is. [ABSTRACT FROM AUTHOR]

Naturally occurring substances and their derivatives function as vital resources for pesticides that can be used in fields, such as insecticide production and fungicide development. As a botanical entity displaying multifaceted biological functions, wormwood has received thorough scrutiny across multiple sectors. The insect repellency potency combined with antibacterial and antifungal activities of wormwood position it as a potential candidate for prospective development into eco-friendly chemical pesticides. In this research, Wormwood essential oil was procured via ethanol water under ultrasonic scenarios and subsequently diluted with PEG 400 to formulate green chemical pesticides. The defensive efficacy of this green pesticide on plants was validated through 2 weeks of clustered plant growth experiments. Active constituents that exerted their effects were scrutinized by GC-MS. Furthermore, this green pesticide also displays efficacious effects on the prevention and management of aphids, exhibiting a dose-dependent relationship. 4-terpenol, eucalyptol, carvacrol, and L-borneol were identified by GC-MS as the predominant active constituents in this green chemical pesticide. Wormwood can be leveraged to develop green chemical pesticides, which can protect plants without contaminating the environment. [ABSTRACT FROM AUTHOR]

With increasing health awareness and the accelerating pace of life, whole-grain prepared foods have gained popularity due to their health benefits and convenience. However, the potential risk of type B trichothecene toxins has also increased, and these mycotoxins in such foods are rarely regulated. In this study, a quantitative method combining a single-valve dual-column automatic online solid-phase extraction system with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) was developed for the first time using restricted-access media columns. This method can simultaneously determine trace residues of seven type B trichothecenes within 15 min. The method is convenient, sensitive (limit of detection and quantification of 0.05–0.6 μg/kg and 0.15–2 μg/kg, respectively), accurate (recovery rates of 90.3%–106.6%, relative standard deviation < 4.3%), and robust (>1000 times). The established method was applied to 160 prepared food samples of eight categories sold in China. At least one toxin was detected in 70% of the samples. Whole-wheat dumpling wrappers had the highest contamination rate (95%) and the highest total content of type B trichothecenes in a single sample (2077.3 μg/kg). Exposure risk assessment indicated that the contamination of whole-grain prepared foods has been underestimated. The total health risk index of whole-wheat dumpling wrappers, which are susceptible to deoxynivalenol, reached 136.41%, posing a significant threat to human health. Effective measures urgently need to be taken to control this risk. [ABSTRACT FROM AUTHOR]

Food safety remains a matter of great concern in most countries and the composition in food is crucial to food safety. It is very important to make sense of the quality and change of food ingredients. In this research, the change of γ-butyrolactone (GBL), one kind of food additive in beverage, had been evaluated by nuclear magnetic resonance (NMR) technique. The 1H-NMR results of seven beverages covering various kinds with spiked GBL indicated that GBL was transformed into dangerous γ-hydroxybutyric acid (GHB) in six popular beverages under certain conditions which could happen during transportation and storage. Further results of quantitative 13C-NMR showed that pH and temperature were two key factors affecting the transforming degree of GBL to GHB. Lower pH and higher temperature will increase the degree of transformation. GHB was a neurotransmitter on the chemical control list, which was absolutely forbidden to be added to food. This nondestructive NMR detecting technology which did not need the complex pretreatment method to directly determine food ingredients can be useful for identifying the risk of food safety from the changes of food composition during transport and storage. [ABSTRACT FROM AUTHOR]

Polyphenols are powerful antioxidants implicated in reducing the risk of human cancer and cardiovascular disease. Chlorogenic acid is a principal polyphenol in coffee, a beverage consumed worldwide on an immense scale. In many countries, coffee is consumed with milk, which has been shown to affect the bioavailability of polyphenols. Here we assessed the interactions of chlorogenic acid with five major milk proteins (α-casein,β-casein,κ-casein,α-lactalbumin, andβ-lactoglobulin) by spectroscopy and molecular docking calculations. The data showed that the number of binding sites in each chlorogenic acid–milk protein complex was close to 1. Fluorescence quenching of milk proteins by chlorogenic acid occurred through a static mechanism and the binding distance was smaller than 8 nm. Binding constant for chlorogenic acid–β-lactoglobulin was larger than those for chlorogenic acid-α-lactalbumin, chlorogenic acid–α-casein, chlorogenic acid–β-casein, and chlorogenic acid–κ-casein. Thermodynamic parameters revealed that Van der Waals forces and hydrogen bond interactions predominated in chlorogenic acid–α-casein and chlorogenic acid–α-lactalbumin complexes; hydrophobic interactions were predominant in chlorogenic acid–β-casein, chlorogenic acid–κ-casein, and chlorogenic acid–β-lactoglobulin. Molecular docking calculations identified chlorogenic acid was located near Pse66, Ile65, and Pro29 in the chlorogenic acid–α-casein adduct, Leu138, Thr126, Gln123, Ser124, Gln167, Ser166, Ser168 in the chlorogenic acid–β-casein adduct, Glu147, Asn123, Val143, Pse149, Pro120, Leu79, Ala148 in the chlorogenic acid–κ-casein adduct, Glu49, Tyr103, Gln54, His32, Trp104, Leu110 in the chlorogenic acid–α-lactalbumin adduct, and Cys66, Leu22, Lys60, Trp61, Ser21, Lys69, Gln59 in the chlorogenic acid–β-lactoglobulin adduct. Notably, the antioxidant activity of chlorogenic acid decreased significantly on interaction with each of the milk proteins (p < 0.05). This study reveals the binding behaviors of chlorogenic acid with five milk proteins and provides basic data that can help to clarify the binding mechanism. [ABSTRACT FROM PUBLISHER]