Assessment of Distribution and Diversity of Pyrrolizidine Alkaloids in the Most Prevalent Boraginaceae Species in Macedonia

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.

UHPLC-Q-TOF analysis of pyrrolizidine alkaloids in North-Macedonian honey

Honey contaminated with pyrrolizidine alkaloids (PAs) could pose a risk for human consumption, being a widely consumed food product. A fast and simple LC/MS method for the analysis of pyrrolizidine alkaloids in honey was optimised to collect occurrence data. The extraction efficiency was evaluated by a systematic study of multiple solvent mixtures and clean-up procedures. The best results for PA extraction were obtained using a formic acid/methanol mixture with subsequent clean-up by the QuEChERS method, resulting in a mean recovery range of 91.8-102%. The method validation showed satisfactory intra-day (RSD < 5.1%) and inter-day precision (RSD < 9.1%). The proposed method was applied to 14 samples. A total of six PAs and two N-oxides were detected, with levels between 89 and 8188 µg/kg. This assessment highlights the potential risk of intoxication and the need for further investigations regarding an effective quality system for manufacturers to control PAs in honey.

Pyrrolizidine Alkaloids-Pros and Cons for Pharmaceutical and Medical Applications

Heterocyclic organic compounds named pyrrolizidine alkaloids (PAs) belong to a group of alkaloids and are synthesized by either plants or microorganisms. Therefore, they are naturally occurring secondary metabolites. They are found in species applied in the pharmaceutical and food industries, thus a thorough knowledge of their pharmacological properties and toxicology to humans is of great importance for their further safe employment. This review is original because it synthesizes knowledge of plant and microbial PAs, which is unusual in the scientific literature. We have focused on the Boraginaceae family, which is unique due to the exceptional richness and diversity of its PAs in plant species. We have also presented the microbial sources of PAs, both from fungi and bacteria. The structure and metabolism of PAs have been discussed. Our main aim was to summarize the effects of PAs on humans, including both negative, toxic ones, mainly concerning hepatotoxicity and carcinogenicity, as well as potentially positive ones for pharmacological and medical applications. We have collected the results of studies on the anticancer activity of PAs from plant and microbial sources (mainly Streptomyces strains) and on the antimicrobial activity of PAs on different strains of microorganisms (bacteria and fungi). Finally, we have suggested potential applications and future perspectives.

Pyrrolizidine alkaloids in borage (Borago officinalis): Comprehensive profiling and development of a validated LC-MS/MS method for quantification

Pyrrolizidine alkaloids (PA) from borage (Borago officinalis) consumed as herb and tea, may pose a food safety risk. Therefore, the European Union (EU) set maximum levels of PA in borage, among other foodstuffs, which are applicable since July 1^st, 2022. Here, a comprehensive LC-MS/MS based profiling of PA and their N-oxides (PANO) in B. officinalis leaves is presented. Based on these results a targeted, quantitative LC-MS/MS method for the determination of individual PA/PANO present in borage was developed. Chromatographic separation was achieved for all PA/PANO detected in B. officinalis. An easy and fast extraction procedure was developed using a design of experiments approach (DOE). The most efficient extraction was achieved using 0.2% formic acid in 10% methanol at a temperature of 47.5 °C for 60 min. The final method was validated and showed good overall accuracy (recoveries 85-121%) and precision (RDS ≤11%). The method was applied to B. officinalis leave material, demonstrating its suitability for the intended purpose. In these borage samples, the acetylated forms, which are not regulated by EU, were among the quantitatively most relevant PA.

Pyrrolizidine alkaloids and health risk of three Boraginaceae used in TCM

Objective: The aim of this study was to systematically explore the pyrrolizidine alkaloids (PAs) type, content and risk assessment in the three Boraginaceae used in TCM, involving Arnebia euchroma (AE), A. guttata (AG), and Lithospermum erythrorhizon (LE). Method: A UHPLC-MS/MS method was established to simultaneously determine eight pyrrolizidine alkaloids (PAs), namely intermedine, lycopsamine, intermedine N-oxide, lycopsamine N-oxide, 7-acetyllycopsamine, 7-acetyllycopsamine N-oxide, echimidine N-oxide, and echimidine in the three herbs. Based on these results, the risk assessment was explored using the routine margin of exposure (MOE) combined with relative potency (REP) for oral and external usage, respectively. Results and Conclusion: Imermedine and imermedine N-oxide were common components in the eight tested PAs. 7-acetyllycopsamine and its N-oxide were not detected in AE; echimidine and its N-oxide were not detected in AG; lycopsamine and its N-oxide, 7-acetyllycopsamine and its N-oxide were not detected in LE. The total contents of 8 PAs in 11 batches of AG was341.56-519.51 μg/g; the content in 15 batches of LE was 71.16-515.73 μg/g, and the content in 11 batches of AE was 23.35-207.13 μg/g. Based on these results, the risk assessment was explored using MOE combined with REP for oral and external usage, respectively. The findings of the risk assessment method of PAs based on MOE combined with the REP factor were consistent with the clinical toxicity results. As an oral herb, AE had low risk or no risk due to its low PA contents, and individual batches of LE were medium risk, while attention should be paid to their clinical use.AG was also low risk. The external use of the three Boraginaceae used in TCM was not associated with any risk. This study systematically explored the PA type and content of the three Boraginaceae used in TCM. Additionally, the refined risk assessment of PAs based on REP provided a more scientific basis for quality evaluation and rational use of the medicinal Boraginaceae used in TCM to improve public health.