Effect of temperature on morphology, ginsenosides biosynthesis, functional genes, and transcriptional factors expression in Panax ginseng adventitious roots

Abstract

This study researched the effect of temperature on growth and ginsenosides accumulation in adventitious root cultures of Panax ginseng. Results showed that the ginseng adventitious roots growth and differentiation ability could be affected faced with different incubation temperatures (15, 20, 25, and 30°C for 35 days). Besides, the research also demonstrated that low‐temperature stimulation could promote the accumulation of ginsenosides and the content of total ginsenosides increased by 2.53 times at 10°C‐7d (10°C for 7 days and then transferred to 25°C for 28 days) compared with that at 25°C. Moreover, the transcriptional levels of functional genes and PgWRKYs were analyzed by this study and the correlation analysis showed that GPS, SS, CYP716A47, CYP716A53v2, UGT74AE2, UGT94Q2, PgWRKY1, PgWRKY3, and PgWRKY8 were significantly correlated with total ginsenosides content. Furthermore, HPLC‐ESI–MSn analyzed that Malonyl‐Rb1 only existed in 10°C‐7d group. Practical applications The survey showed that after a certain time of stimulating P. ginseng adventitious roots at low temperature, the accumulation of ginsenosides could be enhanced as their expression of related genes were regulated. It provides a theoretical foundation for the mass production of ginsenosides by controlling the temperature conditions of P. ginseng adventitious roots.

Mass Production of Panax ginseng C.A. Mey. Root Cultures in Indonesia

“…The fresh weights of the roots incubated at the temperatures of 21°C to 25 °C and 15 °C to 20 °C, were 1 625.98 g ± 333.591 g and 1 461.65 g ± 304.163 g. The statistical analysis revealed that although the roots had higher fresh weight when incubated at 21°C to 25 °C than 15 °C to 20 °C, the difference between the two was not significant. This result corresponds to the study conducted by Wang et al (2019), P. ginseng root growth and ginsenoside accumulation were optimal when incubated at 20 °C to 25 °C.…”

“…These results indicate that the incubation temperature of 15 °C to 20 °C can increase the accumulation of ginsenosides in the root extract. This can be associated with cold temperatures that potentially cause stress to the roots, which trigger them to produce bioactive compounds at higher levels (Wang et al, 2019). The analysis results of each parameter suggest that 21 °C to 25 °C was the optimal range of incubation temperature.…”

“…In large-scale production of root cultures, several important factors can affect biomass growth and accumulation of bioactive compounds, namely the root's genetic factors (Khan et al, 2015), growth media, other physical factors like incubation temperature (Wang et al, 2019), and inoculum weight (inoculum density) (Manuhara et al, 2015;Than et al, 2004). Because of differences in climatic and topographic conditions between Indonesia and South Korea and increasing biomass and ginsenoside accumulation, it is necessary to re-optimize several production procedures, including inoculum weight, media volume, media composition, and incubation temperature.…”

Optimal NPK Fertilizer Combination Increases Panax ginseng Yield and Quality and Affects Diversity and Structure of Rhizosphere Fungal Communities

“…The experiment was conducted in pots (height: 11 cm; upper diameter: 12 cm; lower diameter: 9 cm; bottom with multiple drainage holes), with soil depth maintained at ~9 cm. Whole pots were buried in the soil so that the soil in the pots was in close contact with the ground, and the soil temperature was maintained to reduce the influence of temperature change on ginsenoside synthesis (Cheng et al, 2018 ; Wang et al, 2019 ). The test soil was a dark brown soil with a sandy loam texture and the following properties: pH, 6.38; organic matter, 49.02 g·kg −1 ; available N, 42.08 mg·kg −1 ; available P, 25.82 mg·kg −1 ; and available K, 107.50 mg·kg −1 .…”

Ginsenosides in Panax genus and their biosynthesis

“…Nine PgWRKYs ( PgWRKY 1‒9) in P. ginseng have been identified recently, each of which includes one WRKYGQK sequence motif and one C2H2-type zinc-finger motif. Some of them could respond to cold, salt (NaCl) and various hormone external signals 170 , 171 . Notably, hypothermia stimulus experiments showed that the expression level of five ginsenoside biosynthetic genes viz., GPS , SS , CYP716A53v2 , UGT74AE2 and UGT94Q2 , and three PgWRKYs viz., PgWRKY1 , PgWRKY3 and PgWRKY8 had a strong positive correlation with the production of total ginsenosides, suggesting these PgWRKY s might participate in the biosynthesis of ginsenosides through regulating the pathway genes 171 .…”