“…In particular, phenylbutenoids are major characteristic compounds of this herb and show various biological activities, including anti-asthma, anticancer, anti-inflammatory, chondroprotective, and melanogenic effects [ 18 , 19 ]. Owing to their volatility, gas chromatography–mass spectrometry (GC–MS) is often employed for the analysis of the extracts and oils of plai [ 15 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 ]. Although these studies contributed to the elucidation of chemical constituents in plai, some peaks are still unidentified, and some discrepancies in peak annotations are found in the literature.…”