Spectrum-effect relationship between GC-QTOF-MS fingerprint and antioxidant, anti-inflammatory activities of Schizonepeta tenuifolia essential oil.

Schizonepeta tenuifolia (Benth.) Briq, a traditional Chinese medicine, is an annual herbaceous plant that is widely distributed in China, Japan, and Korea. The essential oil (EO) of S. tenuifolia has antioxidant and anti-inflammatory properties. However, the components contributing to its antioxidant and anti-inflammatory activities remain unclear. This study was aimed at investigating the spectrum-effect relationship between GC-MS fingerprint and the antioxidant and anti-inflammatory effects of S. tenuifolia EO. Here, the fingerprints of EO from 10 batches of S. tenuifolia from various sources were established using GC-MS, and the antioxidant and anti-inflammatory bioactivities were evaluated using 2,2-diphenyl-1-picrylhydrazyl and nitric oxide inhibitory assays, respectively. Finally, 13 common peaks were identified from 10 batches of S. tenuifolia by searching against the standard mass spectra in NIST 14 and comparing the literature retention index. The different sources of S. tenuifolia EO exhibit mild antioxidant activities and significant anti-inflammatory effects. In particular, menthone (peak 3), isomenthone (peak 4), pulegone (peak 7), piperitone (peak 8), and β-caryophyllene (peak 11) might be the dominant constituents responsible for the antioxidant and anti-inflammatory activities of S. tenuifolia EO. This method may provide a time-saving, convenient way to screen the potential effective components of S. tenuifolia EO.