Hydrothermal Ecological Response Of Baicalin Biosynthesis Process In Scutellaria Baicalensis Callus

Scutellaria baicalensis Georgi belongs to the genus Scutellaria,a perennial herb.its roots are used as medicine.It is one of the traditional Chinese medicinal materials with the functions of clearing heat,drying and dampness,anti-bacterial and anti-inflammation,hemostasis and fetus.At present,the research on the biosynthesis pathway and key enzyme genes of medicinal plants has become a hot issue in the quality control of medicinal plants.However,the gene expression of the key enzymes of baicalin secondary metabolism in S.baicalensis is still weak.In this paper,the biomass,the content of baicalin and the expression of key enzyme genes of baicalin synthesis in callus of S.baicalensis were measured under different temperature and water culture conditions.The relationship between hydrothermal ecological factors and baicalin content and key enzyme gene expression was analyzed.The main results were as follows:1.S.baicalensis callus was used as experimental material,under different temperature and water culture Scutellaria callus biomass were determined.The results showed that the fresh and dry callus of S.baicalensis increased with the increase of temperature,and the peak and size of the callus were different at different temperatures.The culture at 30 was more suitable for the ?growth of S.baicalensis callus.Under the different concentrations of PEG,the growth of callus of S.baicalensis Georgi was inhibited to some extent.After the 10 th day of culture,the inhibition of growth was more obvious with the increase of PEG concentration,but the inhibition effect was weakened when the concentration reached 20%.Except for the control group,the dry weight also increased with the increase of the concentration of PEG in the treatment group,presumably because PEG affected the cellular water content but increased the accumulation of dry matter.Finally,the optimum culture temperature of S.baicalensis callus was determined to be 30 and? no PEG culture was added.2.S.baicalensis callus was used as experimental material,the content of baicalin in S.baicalensis Georgi under different temperature and water culture was determined by HPLC and the accumulation was calculated.The results showed that the content of baicalin differed at different temperature and different culture time.Culture below or above 25 is not conducive ?to the synthesis and accumulation of baicalin.The content of baicalin in 25?culture was significantly higher than that of other treatments.The content of baicalin The content of baicalin was the same as that of baicalin at 25?>30?>20?>15?.With the increase of PEG concentration,the content of baicalin was inhibited to a certain extent and the higher the concentration,the lower the baicalin The more obvious the synthesis was,the lower the content was.However,in the 15 th day of culture,the inhibitory effect of 20% PEG began to diminish and the content increased gradually,which showed that CK>5%>10%>20%>15% different amount and content of CK>20%>5%>10%>15%.In this study,the synthesis and accumulation of baicalin were determined at 25 and without PEG culture.?3.S.baicalensis callus was used as experimental material,the expression levels of key genes of baicalin synthesis(PAL,C4 H,CHS,GUS and UBGAT)under different temperature and water culture conditions were detected by real-time fluorescence quantitative PCR.The results showed that different geneshas different expression level under different condition,such as at different temperature and water culture stages.Their interaction These interacted levels of genes affected the synthesis of baicalin.The expression of C4 H,CHS,GUS and UBGAT genes was most active under below 25°C temperature culture,which promoted the synthesis of baicalin.The expression level of PAL gene under 25°C treatment group was significantly higher than other treatments.The content of baicalin was highest at this temperature;when cultured at low concentration of PEG,The expression of PAL,CHS,GUS and UBGAT genes was the most active and promoted the synthesis of baicalin.4.S.baicalensis callus was used as experimental material,expression relationship of baicalin content and key enzyme gene(PAL,C4 H,CHS,GUS,UBGAT)was researched under different temperature and water culture.The results showed that there was a significant negative correlation between the content of baicalin and PAL and GUS gene expression under low temperature conditions.There was a positive correlation between the content of baicalin and PAL gene expression under normal temperature culture,and the content of baicalin under high temperature culture was significant.There was a significant positive correlation between the expression levels of PAL,C4 H and CHS genes;there was a significant negative correlation between the content of baicalin and UBGAT gene expression in normal culture,and the content of baicalin and the expression of PAL,C4 H and UBGAT genes under high concentration of PEG.There is a clear positive correlation.This indicated that the expression of key enzyme genes under different culture conditions had an important influence on the synthesis of baicalin.