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2.
Sci Rep ; 14(1): 51, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167521

RESUMO

Suspect screening and untargeted analysis using UHPLC-qToF are two advanced analytical approaches now used to achieve an extensive chemical profile of samples, which are then typically confirmed through targeted analysis. These techniques can detect a large number of chemical features simultaneously and are currently being introduced into the study of contaminants of emerging concern (CECs) and into the study of the extent of human chemical exposure (the exposome). Here is described the use of these techniques to characterize chemical mixtures derived from the OECD 301F ready biodegradability test (RBT) of a chemical and natural formulation currently used to treat reflux disease and functional dyspepsia. Untargeted analysis clearly evidenced a different behavior between formulations containing only natural products with respect to that containing synthetic and non-naturally occurring substances. Suspect screening analysis improved the untargeted analysis of the omeprazole-based medicine, leading to the tentative identification of a number of omeprazole-derived transformation products, thereby enabling their preliminary quali-quantitative evaluation. Targeted analysis was then performed to confirm the preliminary data gained from the suspect screening approach. The validation of the analytical method for the quantitative determination of omeprazole and its major metabolite, omeprazole sulphide, has provided robust data to evaluate the behavior of omeprazole during the OECD 301F test. Using advanced analytical approaches, the RBT performed on the two products under investigation confirmed that omeprazole is not readily biodegradable, while the medical device made of natural substances has proven to be readily biodegradable.


Assuntos
Refluxo Gastroesofágico , Inibidores da Bomba de Prótons , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Omeprazol , Personalidade
3.
J Mass Spectrom ; 57(8): e4878, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36065819

RESUMO

The evolution of the regulatory framework for medical devices in the EU (Reg 2017/745) has opened the study of complex systems emerging properties. This makes necessary to identify new analytical approaches able of characterizing complex natural substrates as completely as possible. Therefore, omics approaches and advanced analytical methods for the determination of metabolite classes appear to be at the forefront to meet this need. In this perspective, a new approach based on the suspect screening was developed to detect gallotannins. Gallotannins are a class of phenols with a polymeric nature; thus, there are no pure analytical standards available for all possible structures and their quali-quantitative determination in complex natural substrates can be a challenge. A new UHPLC-qToF method was developed and used to create an "in-house tannin database" with a dual purpose: (1) as a classic list of suspects and (2) to identify core fragments common to gallotannins to have another list of putative suspects based on the common fragment. The method was validated. The application of the method to a "system of molecules" extracted from the leaves of Hamamelis virginiana L. (Witch-hazel) allowed to the characterization of a total of 29 phenols by a suspect screening approach. Therefore, 15 gallotannins were putatively annotated while another 3 were confidently identified. All the gallotannins were semiquantified according to external regression curves of gallic acid and hamamelitannin based on core fragments at m/z 125.0244 and m/z 169.0142, the building blocks of the polymers. This new method provides a practical fit-to-purpose approach for the quali-quantitative screening evaluation of gallotannins, useful for creating multivariate control charts applicable in process development of complex natural systems or in quality control. The approach is innovative, and after specific checks, it can in principle be suitable for metabolomic fingerprint analysis of gallotannins among witch-hazel extract (WHE) samples.


Assuntos
Hamamelis , Taninos Hidrolisáveis , Cromatografia Líquida de Alta Pressão/métodos , Hamamelis/química , Taninos Hidrolisáveis/química , Metabolômica , Fenóis/química
4.
Nat Prod Commun ; 9(4): 565-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24868885

RESUMO

The availability of reliable herbal formulations is essential in order to assure the maximal activity and to limit unwanted side-effects. The correct concentration of declared components of herbal products is a matter of health legislation and regulation, but is still a topic under debate in the field of quality control assessment. In the present work specific constituents of artichoke leaf extracts, considered as a test herbal product, were measured by standard spectrophotometric and HPLC methods (for quantitative determination of some components only), and results were correlated with the ESI-MS (showing the full metabolomic fingerprint). Phytocomplex stability over time was also investigated in batches submitted to different storage conditions. The results indicated excellent agreement between the two approaches in the measurement of total caffeoylquinic acids and chlorogenic acid contents, but the metabolomic ESI-MS method approach provides a more complete evaluation and monitoring of the composition of a herbal product, without focusing only on a single/few compound measurements. Therefore, the ESI-MS method can be proposed for the evaluation of the quality of complex matrices, such as those in a phytocomplex. Another aspect lies in the possibility to obtain a broad-spectrum stability control of herbal formulations, requiring minimal sample pre-processing procedures.


Assuntos
Cynara scolymus/química , Cynara scolymus/metabolismo , Mapeamento de Peptídeos/métodos , Folhas de Planta/química , Folhas de Planta/metabolismo , Metabolômica
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