Rapid authentication of different herbal medicines by heating online extraction electrospray ionization mass spectrometry

Sensitive characterization of complex chemical reactions in black garlic preparation based on on-line extraction electrospray ionization mass spectrometry

Changes in chemical composition during food processing and handling are crucial for the alteration of food flavor and function, and accurate characterization of key chemical reaction pathways in complex food matrices is one of the core challenges in food chemistry research. Here, this study attempts to establish a strategy for sensitive characterization of chemical reactions during food processing based on on-line extraction electrospray ionization mass spectrometry (oEESI-MS). The process of making garlic into black garlic, a traditional global flavor food, was chosen as an exemplary research template. The direct MS characterization of raw garlic as well as black garlic samples with different processing times was achieved by using the self-constructed oEESI-MS device. Benefiting from the high tolerance of oEESI-MS to complex matrix interferences, all samples can be fingerprinted directly without any pre-processing or pre-separation. As a result, oEESI-MS achieved a sensitive characterization of the changes of key substances during the preparation of black garlic. Further, a new chemical reaction pathway, the degradation of γ-L-glutamyl-S-allyl-L-cysteine to S-allyl-l-cysteine, was completely demonstrated by analyzing the differential substances before and after the treatment, and verified by standard substances and chemical theory calculations. In conclusion, a complete oEESI-MS-based strategy for tracking the substance changes in food processing was established in this study, which has a widely applicable prospect for the precise setting of food processing time and parameters, and the innovation of processing technology.

Online Monitoring of the Processing of Traditional Chinese Medicine by Neutral Desorption Atmospheric Pressure Chemical Ionization Mass Spectrometry

The pharmacological effects of traditional Chinese medicine (TCM) are closely associated with the processing procedures, which involve a multitude of intricate chemical reactions. Real-time monitoring of the dynamic changes in chemical constituents during TCM processing plays a pivotal role in ensuring quality control of TCM products. Herein, a neutral desorption atmospheric pressure chemical ionization mass spectrometry (ND-APCI-MS) method was developed for online monitoring of the TCM processing. The aerosol generated during the TCM processing was sampled in situ by neutral desorption using N2, followed by online analysis using APCI-MS. Subsequently, orthogonal partial least squares discriminant analysis (OPLS-DA) was employed to analyze the MS data to find the biomarkers associated with the processing. Compared to traditional tissue-based analytical methods, the present method employing aerosols as samples takes advantage of online analysis, nondestructive sampling, and enhanced accuracy. As a conceptual application, the processing of Rehmannia glutinosa was investigated, and several biomarkers associated with the processing were identified. These findings suggest the potential application of ND-APCI-MS for online and in situ monitoring of the processing of TCM.

Rapid toxicity characterization of Aconitum herbal medicines using perfusion nano-electrospray ionization mass spectrometry

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Recent Advances in Sample Preparation and Chromatographic/Mass Spectrometric Techniques for Detecting Polycyclic Aromatic Hydrocarbons in Edible Oils: 2010 to Present

Polycyclic aromatic hydrocarbons are considered to be potentially genotoxic and carcinogenic to humans. For non-smoking populations, food is the main source of polycyclic aromatic hydrocarbons exposure. Due to their lipophilic nature, oils and fats rank among the food items with the highest polycyclic aromatic hydrocarbon content. Consequently, the detection of polycyclic aromatic hydrocarbons in edible oils is critical for the promotion of human health. This paper reviews sample pretreatment methods, such as liquid-phase-based extraction methods, adsorbent-based extraction methods, and the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, combined with detection techniques like mass spectrometry and chromatography-based techniques for accurate quantification of polycyclic aromatic hydrocarbons in edible oils since 2010. An overview on the advances of the methods discussed herein, along with a commentary addition of current challenges and prospects, will guide researchers to focus on developing more effective detection methods and control measures to reduce the potential risks and hazards posed by polycyclic aromatic hydrocarbons.

Development of sequential online extraction electrospray ionization mass spectrometry for accurate authentication of highly-similar Atractylodis Macrocephalae

The accurate and rapid authentication techniques and strategies for highly-similar foods are still lacking. Herein, a novel sequential online extraction electrospray ionization mass spectrometry (S-oEESI-MS) was developed to achieve spatio-temporally resolved ionization and comprehensive characterization of complex foods with multi-components (high, medium, and low polarity substances). Meanwhile, a characteristic marker screening method and an integrated research strategy based on MS fingerprinting, characteristic marker and chemometrics modeling were established, which are especially suitable for the accurate and rapid authentication of highly-similar foods that are difficult to be authenticated by traditional techniques (e.g., LC-MS). Thirty-two batches of highly-similar Atractylodis macrocephalae rhizome from four different origins were used as model samples. As a result, S-oEESI-MS enabled a more comprehensive MS characterization of substance profiles in complex plant samples in 1.0 min. Further, 22 characteristic markers of Atractylodis macrocephalae were ingeniously screened out and combined with multivariate statistical analysis model, the accurate authentication of highly-similar Atractylodis macrocephalae was realized. This study presents a comprehensive strategy for accurate authentication and origin analysis of highly-similar foods, which has potentially significant applications for ensuring food quality and safety.