English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

A method for identifying and quantifying caffeoylquinic acids (CQAs) in aqueous extracts of the leaves of Aster koraiensis (AKAE) using high-performance liquid chromatography coupled with diode-array detection and electrospray ionization mass spectrometry was developed. Six CQAs (5-CQA, 3-CQA, 4-CQA, 3,4-diCQA, 3,5-diCQA, and 4,5-diCQA) in AKAE were identified by comparing their retention times and ultraviolet spectra with those of the corresponding standards, and the results were confirmed by ESI/MS. The developed HPLC method was applied to quantitative analyses of the six CQAs in AKAE, whose contents in AKAE were in the range 2.04–4.00 mg/g. The inhibitory activities of the CQAs against human neutrophil elastase (HNE) were also evaluated; all tested di-CQA isomers showed considerable inhibition of HNE activity, with IC 50  values ranging from 2.09 to 14.20 μM, while three mono-CQAs exhibited no such activity (IC 50  &gt; 100 μM). 3,5-diCQA and 4,5-diCQA inhibited HNE in a mixed-type noncompetitive manner, with inhibition constant ( K i ) values of 0.47 and 1.4 μM, respectively.

Identification and Quantification of Human Neutrophil Elastase Inhibitory Caffeoylquinic Acids in the Leaves of Aster koraiensis