Contents of flavonoid compounds in Dendrobium officinale Kimura et Migo determined by QuEChERS-HPLC-MS/MS: Method validation and influencing factors

Dendrobium officinale Kimura et Migo (D. officinale), a dual-use plant with both botanical medicine and food applications, has gained global popularity. Flavonoids are important bioactive compounds of D. officinale; nevertheless, the quantitative analysis method for flavonoid components is lack, restricting an in-depth understanding of their functions. A QuEChERS method coupled with HPLC-MS/MS was developed to detect 17 flavonoid components of D. officinale. Octadecylsilane was selected as the clean-up sorbent, which exhibited a relatively weak affinity for flavonoids yet an effective removal of pigments from extracts. Method validation showed that limits of detection (LODs) and limits of quantification (LOQs) were 2.1–49.5 and 7.1–165.2 μg/kg, respectively. The recoveries ranged from 73 % to 112 %, with inter-day and intra-day RSDs below 20 %. Among the 17 flavonoids measured, naringenin, rutin and schaftoside were the predominant compounds, with the highest values of 57.18, 563.17 and 67.73 mg/kg, respectively. These three flavonoids accounted for over 80 % of the total content of 17 flavonoids. Moreover, the Multiple Factor Analysis indicated that the origin and cultivation method exerted great influence on the flavonoid concentrations in D. officinale. The results have important implications for further research and utilization of flavonoids in D. officinale.