Method development and validation of phloroglucinol and dieckol in Ecklonia cava using HPLC–DAD

The purpose of this study was to simultaneously analyze and validate phlorotannins, a group of functional compounds in Ecklonia cava, using HPLC–DAD. E. cava was profiled using UHPLC-Q-Orbitrap HRMS, and a total of six phlorotannin components were identified. Among these six compounds, phloroglucinol and dieckol were selected as marker components of E. cava, and a simultaneous analysis method using HPLC–DAD for phloroglucinol and dieckol was developed. Specificity, linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), and matrix effect (ME) were verified using HPLC–DAD. These results complied with validation guidelines. The applicability of this simultaneous analysis method was confirmed by quantifying the contents of phloroglucinol and dieckol in E. cava samples (n = 10) purchased in Korea. This method can be used for quality control, such as standardization or determination of compounds in health functional foods containing E. cava extract.