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merican ginseng or Panax notoginseng ingredients, were analyzed by the developed method, and the ginsenosides were detected. The total ginsenosides contents were close to those mentioned on the label. However, the nine ginsenosides were detected in one batch of health food, whose label did not indicated ginseng, American ginseng or Panax notoginseng. The nine ginsenosides were not detected in the remaining batches of health foods.The health food extract was directly loaded and purified without any complex pretreatment. The UPLC⁃MS/MS method, not only helped shorten the analysis time, but also accurate quantification of low ginsenoside contents in complex matrix samples. The developed method is simple and rapid, with high throughput, thus being suitable for the quantitative analysis of the nine ginsenosides in health foods.Tryptophan (Trp), also known as α-amino β-indolepropionic acid, is an essential amino acid, which is involved in various physiological processes. Studies have shown that tumors, infectious diseases, and neurological diseases are accompanied by Trp-related metabolic disorders. Understanding the excretion of Trp and its metabolites in normal individuals is of great significance for treating Trp-related diseases and monitoring the health. A rapid quantitative method was developed based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Further, this method was applied to the simultaneous determination of Trp and its metabolites, including kynurenine (Kyn), kynurenic acid (KA), 3-hydroxykynurenine (3-OH-Kyn), 3-hydroxyanthranilic acid (3-OH-AA), xanthurenic acid (XA), 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA). The excretion and amount of target compounds in random urine samples collected from healthy participants were studied using this method. Urine sampled its metabolites in urine were large. Due to these large fluctuations in the absolute content, the difference between individuals was not significant. The data generated using 70 urine samples revealed that the amount of excreted Trp being metabolized was 124%-268% of prototype, which further indicated that the excretion after metabolism was the major underlying mechanism. Upon comparing the levels of metabolites in the Trp-5-HT and Trp-Kyn pathways, the results indicated that the levels of 3-OH-AA and 3-OH-Kyn generated upon Trp degradation through the Kyn pathway was higher than those of the other products. Trp was degraded via Kyn pathway to produce 3-OH-AA, which was the main metabolite of Trp found to be present in the body. This manuscript detected the levels of Trp and its metabolites, as well as summarized the characteristics of excretion using random urine samples, which could provide valuable information for clinical practice.Semi-volatile organic compounds (SVOCs) include polycyclic aromatic hydrocarbons (PAHs), phthalic acid esters (PAEs), organochlorine pesticides (OCPs) and nitrobenzenes (NBs). Most of them have carcinogenic, teratogenic, mutagenic and endocrine disrupting effects. Therefore, rapid and accurate determination of SVOCs in water is very important. As the most traditional pretreatment method, liquid-liquid extraction (LLE) has the advantages of wide extraction range, high extraction efficiency, simple operation and lower cost, which is very suitable for the simultaneous extraction of multiclass SVOCs. Dichloromethane has good solubility for most SVOCs, and is slightly soluble in water with low boiling point. It is a good broad-spectrum extractive solvent of organic compounds. selleckchem But at present, there is no detection standard of SVOCs in water in China. In this study, three factors including nitrogen blowing temperature, pH of water sample and extraction time were optimized. It was aimed to establish a liquid-liquid eee spiked levels of 0.02, 0.2, 0.4 μg/L, with the relative standard deviations (n=6) ranging from 1.03% to 17.0%. This method was applied for the determination of 27 surface water samples in Jinan section of the Yellow River. The pollutants were mainly PAEs and PAHs, while NBs were not detected, only two kinds of OCPs were detected at some sites. The method is simple, universal, accurate and precise, and has low detection limit. It is suitable for the simultaneous determination of the 46 SVOCs in surface water and groundwater.QuEChERS pretreatment combined with gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q-TOF/MS) has been investigated for application in screening 244 pesticide residues in chilli. Fresh chilli samples were extracted with acetonitrile, and dried chilli samples were extracted using an acetonitrile/acetic acid (99∶1, v/v) mixture. The two extraction solvents were stored at -20 ℃. After salting out and cleaning by dispersive solid phase extraction (dSPE), heptachlor epoxide B was added as an internal standard, and the resulting residues were dissolved in 1.00 mL acetone. The dissolved sample solution was loaded onto an HP-5MS UI column (30 m×0.25 mm, 0.25 μm) and eluted by GC-Q-TOF/MS with a programmable temperature vaporizer and splitless injection in the full-scan mode. The compensation effects of the analytical protectant (AP) and matrix-matched calibration method on the matrix effect were established. AP could be used in the fresh chilli matrix to compensate for matrix effects, but it was noatios of these 222 pesticides with r 2 greater than 0.99 was 95.46%. At spiked levels of the LOQ, twice the LOQ and 10 times the LOQ in dried chilli, the ratio of the 222 pesticides with recoveries of 60% to 120% were 72.52%, 73.42%, and 81.53%, respectively. The established screening and confirmation method was used to analyze 12 fresh chilli samples and 14 dried chilli samples. Eight pesticides were found in nine fresh chilli samples and three dried chilli samples, all of which were confirmed to be positive after manual identification. The concentrations of these pesticides were lower than the MRLs required by GB 2763-2019 National Food Safety Standard Maximum Residue Limits for Pesticides in Food. The results demonstrate that the established method is rapid, easy to execute, efficient, and reliable. It can be used for the high-throughput screening and quantitation of pesticide residues in fresh and dried chilli.Measurement of additive residues in food contact materials is important for safety monitoring at the initial stage. Most of the current studies focus on the determination of the migration amounts of chemical hazards from food contact materials into food simulants. Studies on chemical hazard residues in food contact materials are limited to monomers, oligomers, heavy metals, phthalic acid esters, and biphenols, which are known environmental pollutants. Only a few studies have investigated analysis methods for additive residues in food contact materials. In this study, the main factors (monitoring wavelength, chromatographic column, mobile phase, extraction solvent, etc.) that affect the accuracy and sensitivity of eight compounds, including three antioxidants, three light stabilizers, and two plasticizers, were investigated during sample preparation and instrument analysis. A method based on ultrahigh-performance liquid chromatography (UPLC) was developed for the simultaneous determination of these eight addithe current legislation. To assess the feasibility and potential of the proposed approach for routine analyses of these eight compounds, the developed method was applied to the analysis of these compounds in ten PE food packages and PE gloves. In six samples, tris(2,4-di-tert-butylphenyl)phosphite (Irganox 168) was detected at a level of 0.02%-0.07%, which was lower than the maximum level of this compound in PE food contact material products regulated in GB 9685-2016 at 0.2%. The method is compliant with the current legislation, and it can be used for the monitoring and supervision of these eight additives in PE food contact materials.Pien-Tze-Huang is one of the most famous traditional Chinese medicine prescriptions and consists of several precious medicinal materials, such as Notoginseng Radix et Rhizoma, Bovis Calculus, Snake Gall, and Moschus. However, its formula has not been completely revealed. It is mainly applied for the treatment of acute and chronic viral hepatitis, carbuncle, and boils caused by blood stasis, unknown swelling, bruises, and various inflammation disorders. The chemical composition of Pien-Tze-Huang is extremely complicated. Thus far, extensive attention has been paid to the principal chemical families in Pien-Tze-Huang, such as ginsenosides, bile acids, and muscone derivatives. Comprehensive chemical profiling, although of immense importance for systematic quality control, has not been achieved. Therefore, we configured a platform, namely online pressurized liquid extraction-ultra-high-performance liquid chromatography-ion trap-time-of-flight mass spectrometry (online PLE-UHPLC-IT-TOF-MS), to characterize the cheful information for the quality control of this famous TCM prescription.In recent years, goat milk powder and camel milk powder have gained popularity among consumers. Due to their potential low allergenicity, these milk powders have become a substitute for breast milk, especially for infants, and for people with lactose intolerance. In this paper, a method was developed for the simultaneous determination of 18 amino acids (AAs), histidine (His), serine (Ser), arginine (Arg), glycine (Gly), aspartic acid (Asp) combined with asparagine (Asn), glutamic (Glu), glutamine (Gln), threonine (Thr), alanine (Ala), proline (Pro), lysine (Lys), tyrosine (Tyr), methionine (Met), valine (Val), isoleucine (Iso), leucine (Leu), and dimer of cysteine (Cys) combined with cysteine (L-Cys-Cys), phenylalanine (Phe), taurine (Tau) in milk, goat milk, and camel milk power. The aim of the research was to compare the three kinds of milk powder from the perspective of the constituent amino acids. Therefore, the amino acid compositions and contents were compared. Thus, 2.0 g of the sample was accurately witable for the large-scale analysis of milk powder samples, and it demonstrates high sensitivity and accuracy for the determination and confirmation of the 18 amino acids in different types of milk powders.Hundreds of endogenous peptides were released from milk proteins within the human mammary gland and some of them possess a variety of bioactive functions. Thus, it is important to investigate human milk endogenous peptides for infant health. Peptidomics based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been used to investigate human milk endogenous peptides. Extraction of endogenous peptides from human milk is an essential and key procedure for analyzing human milk peptides using LC-MS/MS. This study aimed to compare methods for extracting endogenous peptides from human milk using LC-MS/MS. Ultrafiltration methods including that not involving denaturation (UF 1), that involving heat denaturation (UF 2), and that involving chemical denaturation (UF 3), precipitation methods using trichloroacetic acid (PCPN 1) and alcohol (PCPN 2), and an enrichment method using highly ordered mesoporous carbon (OMC) were used to extract endogenous peptides from human milk. Extracted endogenous peptides were then analyzed using LC-MS/MS.