Simultaneous determination of usnic, diffractaic, evernic and barbatic acids in rat plasma by ultra‐high‐performance liquid chromatography–quadrupole exactive Orbitrap mass spectrometry and its application to pharmacokinetic studies

Abstract

Usnea longissima Ach. (Usnea) is used in pharmaceuticals, food and cosmetics. Evernic acid (EA), barbatic acid (BA), diffractaic acid (DA) and usnic acid (UA) are the most typical ingredients in U. longissima and exert a wide variety of biological functions. The study aimed to develop a sensitive method for simultaneous analysis of EA, BA, DA and UA in rat plasma and was applied to pharmacokinetic studies after consumption of UA and ethanol extract from U. longissima (UE). The samples were separated on a BEH C column by gradient elution with 0.5% formic acid in water and in methanol. The relative molecular masses of analytes were obtained in full-scan range from 50.0 to 750.0 m/z under negative ionization mode by UPLC-Q-Exactive Orbitrap MS. All validation parameters, such as lower limit of quantitation, linearity, specificity, precision, accuracy, extraction recovery, matrix effect and stability, were within acceptable ranges and the method was appropriate for biological specimen analysis. The pharmacokinetic results indicated that the absolute bioavailabilities of UA after oral administration of UA and UE reached 69.2 and 146.9%, respectively. Compared with UA in UE, the relative bioavailability of DA, BA and EA reached 103.7, 10.4 and 0.7% after oral administration of UE.

Advances in Research on Bioactivity, Toxicity, Metabolism, and Pharmacokinetics of Usnic Acid In Vitro and In Vivo

“…The pharmacokinetic parameters obtained from compartmental and noncompartmental models were close and the bioavailability was about 77.8%. The pharmacokinetic behavior of usnic acid and phenolic acids, such as barbatic acid, diffractaic acid, and evernic acid, was studied in vivo in another study after intravenous and oral administration of pure usnic acid and extract from U. longissima ; the results showed that the absolute bioavailability of usnic acid was 69.2% and 146.9% after oral administration of usnic acid and ethanolic extract, respectively [ 147 ], indicating that the other coexisting ingredients in the extract can promote the absorption of usnic acid or inhibit its metabolism and elimination, thus, affecting its pharmacokinetic behavior in vivo.…”

A target‐group‐change couple with mass defect filtering strategy to identify the metabolites of “Dogel ebs” in rats plasma, urine and bile

“…Although there are many studies on the chemical constituents of “Dogel ebs” , at present, it is essential to obtain its pharmacokinetic parameters and metabolism information to fully understand the pharmacological effects and mechanism of “Dogel ebs.” Unfortunately, the identification of metabolites and illustration of its metabolic patterns have not yet been studied, except the pharmacokinetics investigations on matrine , which restricted the therapeutic applications and development of “Dogel ebs.” In order to clarify the metabolic mechanism of “Dogel ebs,” a target‐group‐change couple with mass defect filtering strategy was proposed based on high performance liquid chromatography–quadrupole exactive Orbitrap mass spectrometry (HPLC‐Q‐Exactive/MS) and Compound Discoverer software. As previously reported , Compound Discoverer software could provide elemental composition assignment, exact mass measurement, and fragmentation information in Traditional Chinese medicines and their metabolites in biological matrices . The metabolic pathway of the metabolites could be confirmed by the group change of prototype, which was called target‐group‐change technology.…”

Characterisation and identification of chemical constituents in aqueous extract of Fomes officinalis Ames based on ultrahigh‐performance liquid chromatography tandem quadrupole‐Orbitrap high‐resolution mass spectrometry

“…A total of 16 amino acids and four derivatives were characterised based on fragmentation rules, database search, and relevant literature. 19,[30][31][32][33][34] Amino acid is a class of organic compounds containing…”