查找使用阿拉丁产品的科研文献

Ionic liquid-based dispersive liquid–liquid microextraction followed by dispersive solid phase extraction coupled with HPLC-DAD for the determination of sulfonylurea herbicides in soymilk samples

Jilong Li,Weili Xu,Xiujuan Wang,Fengze Wu,Lin Wang,Ji Feng,Zhibing Wang,Hanqi Zhang

Tissue-Specific Metabolite Profiling on the Different Parts of Bolting and Unbolting Peucedanum praeruptorum Dunn (Qianhu) by Laser Microdissection Combined with UPLC-Q/TOF–MS and HPLC–DAD

Ling Li Chen,Shan Shan Chu,Ling Zhang,Jin Xie,Min Dai,Xin Wu,Hua Sheng Peng

Background: Qianhu is a traditional Chinese medicine. It is thought that Qianhu roots will harden after bolting and not be suitable for medicinal purposes. Bolting Qianhu and unbolting Qianhu are referred to as “Xiong Qianhu” and “Ci Qianhu,” respectively. In this study, the properties, microscopic and chemical characteristics of Ci Qianhu and Xiong Qianhu roots were compared using fluorescence microscopy, laser microdissection coupled with ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry, and high-performance liquid chromatography with diode-array detection. Results: Microscopy results showed that the area of secondary xylem in the root increased after bolting, with the cork and secretory canals showing strong fluorescence intensity. A total of 34 peaks, mostly pyranocoumarins, were identified in the tissues of Ci Qianhu and Xiong Qianhu. The secretory canals contained the highest variability of coumarins, whereas the secondary xylem contained the least coumarins. Moreover, seven coumarins, especially the pyran- coumarin, decreased after bolting. Generally, both before and after bolting, coumarin level was the highest in the bark, followed by the middle part, and the lowest in the inner part. Conclusion: Thus, it was indicated that the area of secondary xylem increased after bolting, however the coumarin variant and content decreased in the secondary xylem of Qianhu. The result shows that the quality of Qianhu decreases after bolting, which supports the viewpoint that Xiong Qianhu is not suitable for medicinal use.Keywords:bolting;Peucedanum praeruptorumDunn;microstructure;LMD;UPLC-Q/TOF–MS;HPLC–DAD

HPLC-DAD data coupled with second-order calibration method applied to food analysis: Simultaneous determination of six benzoylurea insecticides in various fruit samples by selecting time region of chromatogram

Qing XiangDong,Wu HaiLong,Nie ChongChong,Li Yong,Yan XiuFang,Zhang XiHua,Yin XiaoLi,Yu RuQin

This work presents a novel application of second-order calibration based on self-weighted alternating trilinear decomposition (SWATLD) algorithm for analyzing the HPLC-DAD data. The proposed method makes it possible to simultaneously determine teflubenzuron, hexaflumuron, flufenoxuron, chlorfluazuron, diflubenzuron and benzoylurea in different fruit samples, i.e. pear, apple and banana, in the selected time region of chromatogram. The concentration, elution time and spectral information of these benzoylurea insecticides are selectively extracted from complex matrices even in the presence of unknown interferences. The root-mean-square error of prediction (RMSEP) and figures of merit, including sensitivity (SEN), selectivity (SEL) and limit of detection (LOD) are employed to access the performance of the method. The LODs obtained for these insecticides are within the range 0.017–0.26 ppm in pears, 0.039–0.33 ppm in apples, 0.041–0.44 ppm in bananas, respectively. Such a chemometrics-based protocol holds great potential to be extended as a promising alternative for more practical applications in food safety and quality monitoring.

Non-Targeted Metabolomic and Chemometric Analysis of Gardeniae Fructus (Zhizi): Linking Processing to Chemical and Bioactive Changes

Ling Liang,Jisheng Liu,Jiangyi Luo,Yasi Deng,Shiqi Liu,Qingling Xie,Mengyun Wang,Tingsi Guo,Xingwang Leng,Pingan Liu,Wei Wang,Hanwen Yuan

Ethnopharmacological relevance Gardeniae Fructus (Zhizi, ZZ), the fruit of Gardenia jasminoides Ellis, exhibits anti-inflammatory and hepatoprotective effects, etc. Processing alters its properties, enhances therapeutic effects, and reduces toxicity. Furthermore, The chemical composition of ZZ seed and pericarp is significantly different. Studying the alterations in chemical components of the seed and pericarp under various processing conditions and the resulting variances in biological activities is highly valuable. Aim of the study: This study aimed to investigate the changes in the chemical composition and biological activity of ZZ during processing. Materials and methods This study employed high-performance liquid chromatography-diode array detection (HPLC-DAD) and liquid chromatography coupled to electrostatic orbitrap high-resolution mass spectrometry (LC-Orbitrap-MS), along with chemometric analysis and non-targeted metabolomics, to investigate variances in components of ZZ seed and pericarp and their transformations during processing. Lipopolysaccharide (LPS)-induced RAW 264.7 cells were utilized to evaluate the anti-inflammatory effects of ZZ by measuring nitric oxide (NO) production with the Griess reagent method. Furthermore, the levels of pro-inflammatory cytokines (TNF-α, IL-6) were determined using ELISA technique. Acetaminophen (APAP)-induced HepG2 cells were used to investigate the hepatoprotective of ZZ. Results Using non-targeted metabolomics and chemometrics, the study identified 353 differential features between the ZZ raw seed (RS) and the raw pericarp (RP). During processing, 382 and 386 significant features were found in seed and pericarp, respectively. A total of 210 compounds were identified by reference standards, fragmentation pattern, molecular networking, mzCloud, mzVault, in-house database, and a predictive database. Furthermore, bioassay tests showed reduced anti-inflammatory and hepatoprotective effects during processing. Geniposide and trans -crocin I were identified as primary anti-inflammatory and hepatoprotective compounds. Conclusion The chemical difference between the pericarp and seed of ZZ is obvious, and the chemical changes during processing have a significant impact on the activities. Proper processing is crucial for maximizing the therapeutic effects of ZZ.

Magnetic dummy template molecularly imprinted particles functionalized with dendritic nanoclusters for selective enrichment and determination of 4-methylnitrosamino-1-(3-pyridyl)-1-butanone (NNK) in tobacco products

Yani Zheng,Yin Dai,Junqiang Hong,Huizhu Fan,Qing Zhang,Wei Jiang,Wei Xu,Jianwen Fei,Junli Hong

The compound 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), one of the tobacco specific nitrosamines (TSNAs), is widely recognized as a major carcinogen found in tobacco products, environmental tobacco smoke and wastewater. Thus, a selective enrichment and sensitive detection method for monitoring the risk of NNK exposure is highly desirable. In this study, a magnetic molecularly imprinted polymer (MMIP) functionalized with dendritic nanoclusters was synthesized to selectively recognize NNK via the dummy template imprinting strategy, aiming to avoid residual template leakage and increase the imprinting efficiency. The nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, as well as vibrating sample magnetometry (VSM) and nitrogen adsorption/desorption analysis. The resulting MMIPs exhibited high adsorption capacity, fast binding kinetics and good selectivity for trace amounts of NNK. A rapid, low cost and efficient method for detecting NNK in tobacco products was established using magnetic dispersive solid-phase extraction coupled with HPLC-DAD with a good linear range of 0.1–250 μg mL−1. The limit of detection (LOD) and limit of quantification (LOQ) of NNK were 13.5 and 25.0 ng mL−1, respectively. The average recoveries were 87.8–97.3% with RSDs lower than 3%. The results confirmed that the MMIPs could be used as an excellent selective adsorbent for NNK, with potential applications in the pretreatment of tobacco products.