SmHPPR1 from Salvia miltiorrhiza regulated the biosynthesis of salvianolic acids / 药学学报

italic>Salvia miltiorrhiza Bunge is a traditional Chinese medicinal herb widely used to treat cardiovascular and cerebrovascular diseases at clinic. Its main water-soluble components are rosmarinic acid (RA) and salvianolic acid B (SAB), which are produced by phenylpropanoid pathway. 4-Hydroxyphenylpyruvate reductase (HPPR) is a key enzyme in phenylpropanoid metabolism pathway. SmHPPR1 was cloned from S. miltiorrhiza and was constructed into plant expression vector pJR-SmHPPR1. On this basis, SmHPPR1 transgenic Arabidopsis plants were induced and the content of 4-hydroxyphenyllactic acid (pHPL) was determined. SmHPPR1-overexpressing (SmHPPR1-OE) hairy roots of S. miltiorrhiza were obtained and the concentration of active components and transcriptome analysis were performed. The results showed that the concentration of pHPL in SmHPPR1 transgenic Arabidopsis T1 was 0.594 mg·g-1 dry weight. The concentration of RA, SAB and total salvianolic acid in SmHPPR1-OE-3 hairy roots were 1.09, 1.29, 1.15 times of that in control-3, respectively, and the content of Danshensu was 36.26% of that in control-3. Transcriptomic analysis revealed that overexpression of SmHPPR1 caused the upregulation of other phenylpropanoid pathway genes like SmTAT2. Protein-protein interaction indicated CYT (TR74706_c0_g1), NADP+ (TR26565_c0_g1) and NADP+ (TR68771_c0_g1) is the central node of the network and participated in metabolic process and cellular process. The tracking work in this study proved that SmHPPR1 could catalyze the reduction of 4-hydroxyphenylpyruvic acid to 4-hydroxyphenyllactic acid in SmHPPR1 transgenic Arabidopsis, and SmHPPR1-overexpressing in hairy roots of S. miltiorrhiza could increase the concentration of salvianolic acids through synergistically regulating other pathway genes.

Rapid identification of medicinal herbs through plant Direct-PCR / 药学学报

Direct-PCR technology was using a 15 minutes heat-lysis step instead of DNA extraction to get DNA templates with small amount of plant materials followed by sensitive PCR process to amplify target genes. In order to facilitate DNA barcoding in medicinal herb identification with Direct-PCR, we collected different tissues from 80 medicinal plants as material to amplify the ITS fragments. Through optimizing the PCR reaction, ITS of 80 plant samples was all successfully amplified. PCR products were sequenced and to do Blast analysis. These results suggest that Direct-PCR would improve the efficiency of DNA barcoding in the application of medicinal herb molecular authentication.

Optimization of induction and culture conditions for hairy roots of Salvia miltiorrhiza / 中国中药杂志

To establish induction and liquid culture system for hairy roots of Danshen (Salvia miltiorrhiza), Agrobacterium rhizogenes A4, LBA9402, 15834 as test bacterium were used to infect aseptic leaves of Danshen. The hairy roots were induced and positive transgenic hairy roots were selected with PCR using rolB and rolC as the target gene. Then hairy roots of S. miltiorrhiza were harvested and salvianolic acids were extracted with 70% methanol containing 1% formic acid. The content of salvianolic acid B (SalB) and rosmarinic acid (RA) were determined by HPLC. According to the above research results, the Danshen hairy roots induced by A. rhizogenes LBA9402 were inoculated into the following group of culture media: MSOH, MS, B5, and 6,7-V liquid media. Then the same methods of extraction and determination for the content of Danshen hairy roots were adopted. Last, the hairy roots of S. miltiorrhiza induced by A. rhizogenes LBA9402 were inoculated into the MSOH liquid media with different pH values. The content of salvianolic acid were extracted with 70% methanol containing 1% formic acid and determined by HPLC. As a result, three kinds of A. rhizogenes A4, LBA9402, 15834 could induce hairy roots and Ri plasmids were integrated into the genome of S. miltiorrhiza by PCR. Danshen hairy roots induced by A. rhizogenes LBA9402 and A4 produced much more salvianolic acid, which were (3.27 ± 0.37)% [including (1.04 ±0.36)% of RA and (2.22 ± 0.29)% of SalB] and (3.17 ± 0.20)% [including (0.92 ± 0.31)% of RA and (2.25 ± 0.26)% of SalB], respectively. Hairy roots induced by A. rhizogenes LBA9402 when they were cultured in MSOH liquid media produced much more salvianolic acid, which was (4.56 ± 0.36)%, including (1.12 ± 0.26)% of RA and (3.44 ± 0.23)% of SalB. Hairy roots induced by A. rhizogenes LBA9402 produced the most salvianolic acid when they were cultured in MSOH liquid media with the pH value 4.81, which was 4.85%, including 1.16% of RA and 3.69% of SalB. So Danshen hairy roots induced by A. rhizogenes LBA9402 and A4 produced much more salvianolic acid when they were cultured in MSOH liquid media with the pH value 4.81. The research had established the foundation on genetic engineering to improve the quality of S. miltiorrhiza.

Determination and biosynthesis of multiple salvianolic acids in hairy roots of Salvia miltiorrhiza / 药学学报

Danshen (Salvia miltiorrhiza Bunge) hairy roots were obtained by infecting Danshen leaves with Agrobacterium rhizogenes 9402. Besides rosmarinic acid (RA) and salvianolic acid B (SAB), the hairy root could also produce salvianolic acid K (SAK), salvianolic acid L, ethyl salvianolic acid B (ESAB), methyl salvianolic acid B (MSAB), and a compound with a molecular weight of 538 (compound 538) identified by using LC-MS. Effects of methyl jasmonate (MeJA) and yeast elicitor (YE) on the accumulation of these compounds had been investigated. MeJA increased the accumulation of SAB, RA, SAK, and compound 538 from 4.21%, 2.48%, 0.29%, and 0.01% of dry weight to 7.11%, 3.38%, 0.68%, and 0.04%, respectively. YE stimulated the biosynthesis of RA from 2.83% to 5.71%, but depressed the synthesis of SAB, SAK and compound 538. It was indicated in all the results that these Danshen hairy roots could be used as alternative resources to produce salvianolic acids. Analysis of the content variation of these compounds after elicitation suggested that SAK and compound 538 might be the intermediates in the biosynthesis from RA to SAB in Danshen hairy roots.