Two New Compounds Isolated from the Itea omeiensis and Their Anti-oxidant Activities

Two new compounds (1-2) together with ten known compounds (3-12) were isolated for the first time from the 95 % EtOH extract of aerial parts of Itea omeiensis. Their structures were elucidated based on extensive spectroscopic analyses and comparison with published data. The structure of 1 was further confirmed through single-crystal X-ray diffraction analysis, and circular dichroism (CD) spectrum in combination with acid hydrolysis was employed for the absolute configuration determination of 2. Compound 1 was the first 2-arylbenzo[b]furan with an extra six-membered lactone ring from Itea plants. Anti-oxidant assays indicated that compound 1 possessed significant radical scavenging effects on 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⋅+ ) with IC50 values of 0.14 and 0.06 mg/mL, respectively, which were comparable to the positive control of ascorbic acid. However, no obvious anti-hepatocellular carcinoma activity was observed for compounds 1 and 2.

Comprehensive and Rapid Identification of Astilbin Metabolites in Rats Based on Multiple Metabolite Templates Combined with UHPLC-Q-ExactiveMass Spectrometry

BACKGROUND

Astilbin, a dihydroflavonoid compound widely found in plants, exhibits a variety of pharmacological activities and biological effects. However, little is known about the metabolism of this active compound in vivo, which is very helpful for elucidating the pharmacodynamic material basis and application of astilbin. <P> Objective: To establish a rapid profiling and identification method for metabolites in rat urine, faeces and plasma using a UHPLC-Q-Exactive mass spectrometer in negative ion mode. <P> Methods: In this study, a simple and rapid systematic strategy and 7 metabolite templates, which were established based on previous reports, were utilized to screen and identify astilbin metabolites. <P> Results: As a result, a total of 72 metabolites were detected and characterized, among which 33 metabolites were found in rat urine, while 28 and 38 metabolites were characterized from rat plasma and faeces, respectively. These metabolites were presumed to be generated through ring cleavage, sulfation, dehydrogenation, methylation, hydroxylation, glucuronidation, dehydroxylation and their composite reactions. <P> Conclusion: This study illustrated the capacity of the sensitive UHPLC-Q-Exactive mass spectrometer analytical system combined with the data-mining methods to rapidly elucidate the unknown metabolism. Moreover, the comprehensive metabolism study of astilbin provided an overall metabolic profile, which will be of great help in predicting the in vivo pharmacokinetic profiles and understanding the action mechanism of this active ingredient.