Validation, measurement uncertainty, and application of sesquiterpenoids and curcuminoids in turmeric (Curcuma longa L.) using HPLC-DAD and UHPLC-ESI-MS/MS

Liquid chromatography-diode array detection (HPLC-DAD) and ultra-high-performance liquid chromatography (UHPLC)-electrospray ionization tandem mass spectrometry (ESI-MS/MS) methods were investigated for the simultaneous determination of five bioactive compounds in the rhizome and tuberous root of Curcuma longa L. (turmeric). These belonging to the two chemical groups: three curcuminoids (curcumin, bisdemethoxycurcumin, and demethoxycurcumin) and two sesquiterpenoids (ar-turmerone and bisacurone). The established analytical method was validated based on AOAC guidelines for specificity, linearity, accuracy, and precision. Additionally, the system suitability test and measurement uncertainty were also estimated. The validated method was successfully applied to evaluate the quality of 25 commercial turmeric samples. This proposed method can be applied in practice for the quality control indicator of turmeric, such as its functionality and stability. Therefore, the development of this analytical method represents a significant advancement in the quality assessment of turmeric, offering a valuable tool for food industries reliant on this particular spice and ingredient.