Development and validation of two methods based on high‐performance liquid chromatography‐tandem mass spectrometry for determining 1,2‐benzopyrone, dihydrocoumarin, o‐coumaric acid, syringaldehyde and kaurenoic acid in guaco extracts and pharmaceutical preparations

Abstract

In this study, two HPLC-ESI-MS/MS methods were developed and validated for the determination of 1,2-benzopyrone (COU), o-coumaric acid (OCA), kaurenoic acid (KAU), syringaldehyde (SYR), and dihydrocoumarin (DIH) in guaco extracts and pharmaceutical preparations (syrup and oral solution). The chromatographic separation was achieved using a C18 XBridge 150×2.1-mm (5-μm particle size) column maintained at 25°C. The mobile phases consisted of a gradient of water and acetonitrile containing 0.05% formic acid or 5 mM ammonium formate for the positive and negative ion modes, respectively. All of the calibration curves showed excellent coefficients of correlation (r≥0.9970) over the ranges of 1.25-400 ng/mL for coumarin, 10-600 ng/mL for dihydrocoumarin, 5-250 ng/mL for KAU, and 25-500 ng/mL for o-coumaric acid and syringaldehyde. The range of recovery was 96.3-103% with an RSD% of <4.85% for intraday and interday precision. The results indicate that the developed methods are fast, efficient, and sensitive for the quantification of the guaco metabolites in extracts and pharmaceutical forms while avoiding purification and derivatization steps.

A Kinetic Study of the Main Guaco Metabolites Using Syrup Formulation and the Identification of an Alternative Route of Coumarin Metabolism in Humans

“…Samples of guaco syrup (same brand and lot) containing 0.295 mg/mL of COU, 0.018 mg/mL of OCA and 0.148 mg/mL of KAU, were obtained from local markets (Curitiba, Brazil). The amounts of each compound were determined by HPLC-MS/MS [24]. Methanol and acetonitrile (HPLC grade) were purchased from Tedia (Fairfield, USA), and formic acid (88%) was obtained from J. T. Baker Chemicals B.V. (Deventer, the Netherlands).…”

“…Because the toxic and therapeutic effects of the main guaco metabolites are dose-dependent and the dosages of these compounds are not standardized in guaco phytomedicines [24,25], monitoring the kinetics of COU, 7-HCOU, OCA and KAU following guaco syrup administration has become important, especially to understand the half-life of these substances and to propose the correct posology of preparations without putting human health at risk.…”

Mikania glomerata and M. laevigata: Clinical and Toxicological Advances

“…Detailed screenings revealed the presence of alcohols, acids, esters, aldehydes, organic esters, terpenes, diterpenes, triterpenes and steroids, among other metabolites; some of them are associated with the therapeutic effects of guaco (Gasparetto et al, 2010). A wide variation in metabolite content has been observed among different extracts and pharmaceutical preparations (Gasparetto et al, 2011). In fact, the geographic origins, agronomic aspects, extraction solvent and extraction techniques have been described as crucial factors to obtain a desirable substance.…”

“…In humans, the majority of tests for mutagenicity and genotoxicity also suggest that coumarin is not a toxic agent (Lake, 1999). The lack of toxicity has been associated with the detoxification mechanism of coumarin, which in humans involves the 7-hydroxylation pathway, a minor route in rats and mice; these rodents use the 3,4-epoxidation pathway instead, which results in toxic metabolite formation (Gasparetto et al, 2011). Thus, the species-specific target organ toxicity has been attributed to the pharmacokinetics of coumarin metabolism, causing rats to be susceptible to liver effects and mice to have toxicity particularly in the lung.…”

Total content of kaurene diterpenes in Annona vepretorum stems via 1H qNMR: A method for speeding the identification of bioactive extracts

“…Several biological properties have been described for KDs, namely anti‐inflammatory, antinociceptive, trypanocidal, antifungal, antibacterial, larvicidal, and anti‐HIV . Up to now, mostly HPLC and GC‐based methods have been employed to determine contents of different KDs in plants . However, chromatography methods often require complicated sample preparation and are time‐consuming.…”