This study evaluated five bioactive marker compounds—chlorogenic acid, lactucin, quercetin, scutellarin, and lactucopicrin—in three lettuce (Lactuca sativa) cultivars: 'Cheongchima', 'Cheongharang I', and 'Cheongharang II', using HPLC with UV detection. The method showed excellent linearity (R²>0.999), with detection limits of 0.36 to 1.51㎍/mL and quantification limits between 1.09 and 4.56 ㎍/mL. It also exhibited good precision (relative standard deviation, RSD: 0.11- 3.93%) and accuracy (RSD: 0.04-3.50%) with recovery rates of 95.06-104.28%. Among extracts, the 60% ethanol extract of 'Cheongharang I' exhibited the highest levels of chlorogenic acid (745.34㎍/mL) and quercetin (632.08㎍/mL). Lactucin was most abundant in the 0% ethanol extract of 'Cheongharang II', while scutellarin peaked in the 60% ethanol extract of 'Cheongharang I' (1,945.47㎍/mL). Lactucopicrin was highest in the 100% ethanol extract of 'Cheongharang II' (23.49㎍/mL). These findings provide a reliable analytical basis for quality control and bioactive profiling of lettuce cultivars.
Moon et al. (Sun,) studied this question.