Determination of pyrrolizidine alkaloids in tea and honey with automated SPE clean-up and ultra-performance liquid chromatography/tandem mass spectrometry

Mass spectrometric analysis strategies for pyrrolizidine alkaloids

Pyrrolizidine alkaloids (PAs) in food and natural preparations have received widespread attention due to their hepatotoxicity, genotoxicity, and embryotoxicity. Mass spectrometry (MS), as a high resolution, high sensitive, and high throughput detection tool, has been the most commonly used technique for the determination of PAs. The continuous advancement of new technologies, methods, and strategies in the field of MS has contributed to the improvement of the analytical efficiency and methodological enhancement of PAs. This paper provides an overview of the structure, toxicity properties and commonly employed analytical methods, focusing on the concepts, advances, and novel techniques and applications of MS-based methods for the analysis of PAs. Additionally, the remaining challenges, future perspectives, and trends for PA detection are discussed. This review provides a reference for toxicological studies of PAs, content monitoring, and the establishment of quality control and safety standards for herbal and food products.

Assessment of Toxic Pyrrolizidine and Tropane Alkaloids in Herbal Teas and Culinary Herbs Using LC-Q-ToF/MS

Pyrrolizidine alkaloids are secondary metabolites produced by plants as a defense against insects. These can cause acute or chronic toxicity in humans. Therefore, avoiding potential poisoning from the consumption of tea and culinary plants contaminated with pyrrolizidine alkaloids (PAs), pyrrolizidine alkaloids N-oxides (PANOs), and tropane alkaloids (TAs) is important for human health and food safety. Therefore, it is important to determine the levels of these substances with reliable and highly accurate methods. In this study, the PAs, PANOs, and TAs in herbal teas and culinary herbs sold in Turkish markets were identified and their levels were determined. Thus, the general profiles of herbal teas and culinary herbs in Turkey were revealed, and the compliance of the total amounts of PA and TA with the regulations was examined. The identification and quantification of 25 PAs and N-oxides and 2 TAs (atropine and scopolamine) in the samples was performed with a liquid chromatography-quadrupole time-of-flight tandem mass spectrometer (LC-Q-ToF/MS). At least a few of these substances were detected in all of the tested herbal teas and culinary herbs. The total contents of the black tea, green tea, mixed tea, flavored tea, chamomile tea, sage tea, linden tea, fennel tea, rosehip tea, peppermint, and thyme samples ranged from 4.6 ng g-1 to 1054.5 ng g-1. The results obtained shed light on the importance of analyzing the total dehydro PA, PANO, and TA amounts in plant-based products consumed in diets with sensitive and accurate methods, and they highlight the necessity of performing these analyses routinely in terms of food safety.

Quantitative Analysis of Bioactive Compounds in Commercial Teas: Profiling Catechin Alkaloids, Phenolic Acids, and Flavonols Using Targeted Statistical Approaches

Tea, an extensively consumed and globally popular beverage, has diverse chemical compositions that ascertain its quality and categorization. In this investigation, we formulated an analytical and quantification approach employing reversed-phase ultra-high-performance liquid chromatography (UHPLC) methodology coupled with diode-array detection (DAD) to precisely quantify 20 principal constituents within 121 tea samples spanning 6 distinct variants. The constituents include alkaloids, catechins, flavonols, and phenolic acids. Our findings delineate that the variances in chemical constitution across dissimilar tea types predominantly hinge upon the intricacies of their processing protocols. Notably, green and yellow teas evinced elevated concentrations of total chemical moieties vis à vis other tea classifications. Remarkably divergent levels of alkaloids, catechins, flavonols, and phenolic acids were ascertained among the disparate tea classifications. By leveraging random forest analysis, we ascertained gallocatechin, epigallocatechin gallate, and epicatechin gallate as pivotal biomarkers for effective tea classification within the principal cadre of tea catechins. Our outcomes distinctly underscore substantial dissimilarities in the specific compounds inherent to varying tea categories, as ascertained via the devised and duly validated approach. The implications of this compositional elucidation serve as a pertinent benchmark for the comprehensive assessment and classification of tea specimens.

Risk assessment of short-term intake of pyrrolizidine alkaloids in food: derivation of an acute reference dose

Pyrrolizidine alkaloids (PA) are phytochemicals that are known to act as human hepatotoxins and are also considered to be genotoxic carcinogens. Several plant-derived foods are frequently contaminated with PA, like teas and herbal infusions, spices and herbs or certain food supplements. With respect to the chronic toxicity of PA, the carcinogenic potential of PA is generally regarded as the critical toxicological effect. The risk assessment of the short-term toxicity of PA, however, is internationally less consistent. The characteristic pathological syndrome of acute PA toxicity is hepatic veno-occlusive disease. High PA exposure levels may lead to liver failure and even death as documented by several case reports. In the present report, we suggest a risk assessment approach for the derivation of an acute reference dose (ARfD) for PA of 1 µg/kg body weight per day based on a sub-acute animal toxicity study in rats after oral PA administration. The derived ARfD value is further supported by several case reports describing acute human poisoning following accidental PA intake. The here derived ARfD value may be used for PA risk assessment in cases where the short-term toxicity of PA is of interest in addition to the assessment of the long-term risks.

Simultaneous Determination of 32 Pyrrolizidine Alkaloids in Two Traditional Chinese Medicine Preparations by UPLC-MS/MS

Pyrrolizidine alkaloids (PAs) constitute a class of phytotoxin which demonstrates strong hepatotoxicity. In China, many plants containing PAs are used as traditional medicines or medicinal preparations, which could harm human health and safety. Xiaoyao Tablet (XYT) is an antidepressant drug registered in the European Union (EU), Compound Danshen Dropping Pills (CDDP) is a commonly used drug for coronary heart disease, and phase III clinical study is ongoing in the United States. The purpose of this study is to provide data to support the use of Chinese medicine preparations internationally and to establish analytical methods for 32 PAs in XYT and CDDP. The extraction parameters that were optimized include solid-phase extraction (SPE) cartridge, extraction method, and extraction solvent. Then ultra-performance liquid chromatography coupled with triple-quadrupole linear ion-traptandem mass spectrometry (UPLC-MS/MS) was developed to effectively and efficiently quantify the 32 PAs of the XYT and CDDP. The analytical methods for XYT and CDDP were verified respectively. For XYT, the analytical method for 32 PAs was linear, and the correlation coefficient r was greater than 0.994; the recovery (REC%) at 10-2000 μg/kg was 73.3%-118.5%, and the relative standard deviation (RSD%) was 2.1%-15.4%. The CDDP REC% was 71.8%-112.0%, and the RSD% was 2.0%-17.1%. This study provides technical and data support for the registration of Chinese patented medicines in the EU, controls quality and ensures safety, and is committed to the internationalization and standardization of Chinese patented medicines.