Abstract: The content levels of coixol in roots, stems, leaves and seeds of coix (Coix lacryma-jobi L.) during six growth periods, namely, seedling, tillering, jointing, booting, blooming, and maturity were investigated, and the synthesis and accumulation pattern of coixol in coix plants were clarified. Samples of roots, stems, leaves and seeds of coix were collected during different growth periods, extracted by the ultrasound-assisted extraction method, and the content of coixol was detected by liquid chromatography coupled with mass spectrometry (UPLC-MS/MS). The results showed that there were significant differences in the content of coixol in different parts of coix at different growth stages, and the highest content of coixol was found in roots[(661.06±52.41) mg/kg], followed by leaves [(80.73±2.31) mg/kg], seeds [(14.56±0.29) mg/kg] and stems [(9.80±0.44) mg/kg]. The content of coixol in each part was negatively correlated with plant height, root length, and fresh weight. Comparison of different parts of the plant revealed that coix obtained the greatest coixol yield at the booting stage [(112.47±9.20) mg/plant], followed by the blooming stage [(51.42±7.96) mg/plant]. Coixol yield per plant was positively correlated with plant height, root length and fresh weight. It could be seen that the maximum accumulation of coixol was in the roots at the booting stage.

Key words: Coix lacryma-jobi L., coixol, part, growth period, accumulation pattern