Synergistic effects of ultraviolet-B and methyl jasmonate on tanshinone biosynthesis in Salvia miltiorrhiza hairy roots

• Tanshinones in S. miltiorrhiza hairy roots were stimulated by 40 μW/cm2 UV-B.
• 100 μM MeJA increased total tanshinone content to 1.5 mg/g DW.
• The combined elicitation induced a 4.9-fold increase in tanshinone production.
• SmHMGR and SmGGPPS expression were promoted during the elicitation.

Tanshinones are major bioactive diterpenoids of Salvia miltiorrhiza roots used for the treatment of cardiocerebral diseases. To develop effective elicitation and bioprocess strategies for the enhanced production of tanshinones, ultraviolet-B (UV-B) irradiation and methyl jasmonate (MeJA) elicitation were applied alone or in combination respectively in S. miltiorrhiza hairy root cultures. Our results showed 40-min UV-B irradiation at 40 μW/cm2 stimulated tanshinone production without any suppression of root growth, suggesting a new effective elicitor to S. miltiorrhiza hairy root cultures for tanshinone production. Moreover, the combined treatment of UV-B irradiation and MeJA exhibited synergistic effects on the expression levels of 3-hydroxy-3-methylglutaryl-CoA reductase (SmHMGR) and geranylgeranyl diphosphate synthase (SmGGPPS) genes in the tanshinone biosynthetic pathway. When hairy roots of 18-day-old cultures were exposed to the combined elicitation for 9 days, the maximum production of tanshinone reached to 28.21 mg/L, a 4.9-fold increase over the control. The combined elicitation of UV-B and MeJA was firstly used to stimulate the production of biologically important secondary metabolites in hairy root cultures.

Figure optionsDownload as PowerPoint slide