Effects of ecological factors on ginsenosides synthesis and its key enzyme genes expression / 中草药

ABSTRACT

Objective To explore the effect of ecological factors and the expression of key enzyme genes on the synthesis and accumulation of ginsenosides. Methods Cultivated four-year-old ginseng were used as test materials, the expression of key enzyme genes (HMGR, FPS, SS, SE, DS, β-AS, CYP82D47, CYP716A47) in the biosynthesis of ginsenosides of roots in different growth periods was determined by real-time quantitative PCR, determination of the content of eight ginsenosides (ginsenoside Rg1, Re, Rf, Rb1, Rb2, Rb3, Rc, Rd) in roots by HPLC, the meteorological data were collected by a small weather station, correlation analysis was performed with SPSS. Results The expression of key enzyme genes in the period of flowering to fruit ripening was higher than the root growing after fruit period and the withering period, the expression of key enzyme genes involved in the synthesis of ginsenosides was influenced by each other, and the expression of key enzyme genes in ginseng roots showed a positive correlation with the accumulation of ginsenosides; The contents of ginsenoside Rg1, Rb1, Re, and Rc were higher in the roots of ginseng, eight kinds of monomer ginsenosides content dynamic changes trend is different; Temperature, photosynthetically active radiation, soil water potential are important ecological factors for ginsenosides synthesis in roots, temperature was significantly negatively correlated with ginsenoside Rb1 and Rd (P < 0.05), PAR can significantly promote the formation of ginsenoside Rg1 (P < 0.05), soil water potential was significantly negatively correlated with ginsenoside Rb1 (P < 0.05); Grey correlation analysis results showed that the major ecological factors that influenced ginsenosides content in ginseng roots were temperature, PAR and relative humidity, the grey correlation between the expression of the key enzyme genes with the content of ginsenosides is less than ecological factors with the content of ginsenosides, under the guidance of ecological factors, the expression of the key enzyme genes regulate the synthesis and accumulation of ginsenosides. Conclusion The dynamic changes of the expression of key enzyme genes and the content of ginsenosides in ginseng were determined, it provides a theoretical basis for elucidating the physiological and ecological mechanism of ginsenoside synthesis and the quality control of Radix Ginseng.