Influence of cytokinins and yeast extract on growth and flavone production in hairy root cultures of Scutellaria baicalensis

Hairy roots produce various bioactive chemical compounds than wild-type roots which offer a promising in vitro approach for synthesizing important nutraceutical compounds. The purpose of this study is to increase the production of flavone compounds in hairy root cultures of Scutellaria baicalensis by the addition of elicitors such as cytokinins and yeast extract. Cytokinins such as kinetin (KIN), 6-benzylaminopurine (BAP), and Thidiazuron (TDZ) were utilized at 0.1, 0.5, and 1.0 mg/L, whereas for yeast extract treatment 50, 100, and 150 mg/L concentrations were added to the ½ SH medium. Effects of elicitors were measured in terms of dry biomass and flavone contents (baicalin, baicalein, and wogonin) using high-performance liquid chromatography (HPLC). The highest dry weight was achieved in the control hairy root than that of all cytokinins-treated hairy root cultures. In all the cytokinin-treated hairy root cultures, as the concentration increased the dry weight of the hairy root decreased. In contrast, in all the yeast extract-treated hairy root cultures as the concentration increases the dry weight of the hairy root increased, whereas the highest dry weight was achieved in 150 mg/L of yeast extract. Moving to the flavone content, baicalin was detected highest content in all the hairy root cultures supplied with cytokinin and yeast extract. The highest total flavone content was achieved in the hairy root culture treated with 1.0 mg/L of TDZ and 50 mg/L of yeast extract. This result might help the commercial agronomic sector by facilitating the in vitro mass production of nutraceuticals using S. baicalensis hairy root cultures

Influence of pectin on phenylpropanoid accumulation in buckwheat (Fagopyrum esculentum) sprout

Buckwheat (Fagopyrum esculentum Monech) contains several secondary metabolites like phenolic chemicals. Pectin has been demonstrated to be an efficient elicitor from the biotic group for triggering the defensive response, which enhances the production of secondary metabolites. In this study, the effect of pectin on the growth of buckwheat sprouts and the production of phenylpropanoid compounds in common buckwheat sprouts was investigated by using high-performance liquid chromatography (HPLC). Pectin treatments of 0, 2, 4, 6, and 8 mg/L were administered on buckwheat sprouts for ten days to assess the growth characteristics and optimum concentrations. In comparison to the control treatment, 2 mg/L pectin enhances the shoot length by 24%. But when pectin concentration continued to rise, a tendency toward shorter shoots was seen. Pectin treatment decreased the fresh weight of the sprout as compared to the control treatment. The phenylpropanoid accumulation in buckwheat sprouts varied depending on the amount of pectin utilized. Pectin treatment at 6 mg/L resulted in a 15.10% increase in total phenylpropanoid accumulation. The findings of this study indicate that pectin is a possible elicitor, however, more research on how pectin affects the buildup of phenylpropanoids in buckwheat sprouts would be more intriguing to examine the implications of this work

Expression Analysis of Phenylpropanoid Pathway Genes and Metabolomic Analysis of Phenylpropanoid Compounds in Adventitious, Hairy, and Seedling Roots of Tartary Buckwheat

Tartary buckwheat (Fagopyrum tataricum) is an important crop that belongs to the Polygonaceae family, whose roots have received considerable attention due to the presence of compounds with high nutritional and medicinal value. In this study, we aimed to develop an efficient protocol for the culture of adventitious (ARs) and hairy (HRs) roots on a half-strength Schenk and Hildebrandt (SH) medium containing different concentrations of the auxins, α-naphthaleneacetic acid (NAA), indole-3-butyric acid (IBA), and indole-3-acetic acid (IAA). The highest percentage of root induction (91.67%) was achieved with 0.5 mg/L IAA, whereas the greatest number of roots was found in 1 mg/L IAA. In contrast, 0.1 mg/L IBA returned the longest roots. As expected, HRs were obtained from in vitro leaf explants infected with Agrobacterium rhizogenes R1000. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis of 11 phenolic pathway genes revealed that five genes (FtPAL, FtC3H, FtHQT, FtCHS, and FtANS) were highly expressed in HRs, whereas only four (FtC4H, FtFLS2, FtDFR, and FtANR), and three (Ft4CL, FtCHI, and FtF3H) were recognized in the ARs and seedling roots (SRs), respectively. HPLC analysis of phenolic compounds in different root cultures showed that the majority of the phenolic compounds (both individual and total) were significantly accumulated in the HRs. Principal component analysis (PCA) identified differences among the three root types, whereby HRs were separated from ARs and SRs based on the amount of phenolic compounds present. Analysis of the metabolic pathway revealed that among the identified metabolites, the 3, 2, and 1 pathways were associated with flavonoid, flavone and flavonol, and phenylpropanoid biosynthesis, respectively. Hierarchical clustering analysis and the heat map showed that the different root cultures presented unique metabolites

Influence of Different Types of Carbon Sources on Glucosinolate and Phenolic Compounds in Radish Sprouts

Radish sprouts are valued as a key nutrient-dense food in Asian countries. In the current study, we examined how radish sprouts responded to treatments with various carbon sources. The influence of those treatments in parameters such as plant growth and glucosinolate and phenolic compounds levels were analyzed. A positive correlation between plant growth and the accumulation of glucosinolates and phenolics was observed. In this study, except for galactose treatment, all other carbon-exposed radish sprouts showed the highest shoot and root length and fresh weight. Seven different glucosinolate and five phenolic compounds were identified in radish sprouts. The total glucosinolates and phenolic compound content were increased after treatments with different carbon sources. Radish sprouts exposed to sucrose showed the highest total glucosinolates and phenolics content, which was 1.22-fold and 1.45-fold higher than that of untreated sprouts, respectively. Moreover, sucrose exposure led to a higher production of glucoiberin, gluconapoleiferin, 4-hydroxyglucobrassicin, glucoerucin, glucoraphasatin, glucobrassicin, gallic acid, sinapic acid, rutin, and p-coumaric acid compared to that of untreated sprouts. The results obtained in this study will be helpful for researchers around the world to enhance specific glucosinolate and phenolic compounds by treating the radish sprout plants with suitable carbon sources

Identification, In Silico Characterization, and Differential Expression Profiles of Carotenoid, Xanthophyll, Apocarotenoid Biosynthetic Pathways Genes, and Analysis of Carotenoid and Xanthophyll Accumulation in <i>Heracleum moellendorffii</i> Hance

Heracleum moellendorffii Hance is a non-woody forest plant widely used in China, Korea, and Japan because of its various therapeutic properties. However, the genetic details of the carotenoid pathway (CP), xanthophyll pathway (XP), and apocarotenoid pathway (AP) genes have not been studied. Thus, the CP, XP, and AP genes of H. moellendorffii were detected and analyzed. A total of fifteen genes were identified, of which eight, four, and three belonged to CP, XP, and AP, respectively. All identified genes possessed full open reading frames. Phylogenetic characterization of the identified gene sequences showed the highest similarity with other higher plants. Multiple alignments and 3D dimensional structures showed several diverse conserved motifs, such as the carotene-binding motif, dinucleotide-binding motif, and aspartate or glutamate residues. The results of real-time PCR showed that the CP, XP, and AP genes were highly expressed in leaves, followed by the stems and roots. In total, eight different individual carotenoids were identified using HPLC analysis. The highest individual and total carotenoid content were achieved in the leaves, followed by the stems and roots. This study will provide more information on the gene structure of the CP, XP, and AP genes, which may help to increase the accumulation of carotenoids in H. moellendorffii through genetic engineering. These results could be helpful for further molecular and functional studies of CP, XP, and AP genes

Impact of Light and Dark Treatment on Phenylpropanoid Pathway Genes, Primary and Secondary Metabolites in <i>Agastache rugosa</i> Transgenic Hairy Root Cultures by Overexpressing <i>Arabidopsis</i> Transcription Factor <i>AtMYB12</i>

Agastache rugosa, otherwise called Korean mint, has a wide range of medicinal benefits. In addition, it is a rich source of several medicinally valuable compounds such as acacetin, tilianin, and some phenolic compounds. The present study aimed to investigate how the Tartary buckwheat transcription factor AtMYB12 increased the primary and secondary metabolites in Korean mint hairy roots cultured under light and dark conditions. A total of 50 metabolites were detected by using high-performance liquid chromatography (HPLC) and gas chromatography–time-of-flight mass spectrometry (GC-TOFMS). The result showed that the AtMYB12 transcription factor upregulated the phenylpropanoid biosynthesis pathway genes, which leads to the highest accumulation of primary and secondary metabolites in the AtMYB12-overexpressing hairy root lines (transgenic) than that of the GUS-overexpressing hairy root line (control) when grown under the light and dark conditions. However, when the transgenic hairy root lines were grown under dark conditions, the phenolic and flavone content was not significantly different from that of the control hairy root lines. Similarly, the heat map and hierarchical clustering analysis (HCA) result showed that most of the metabolites were significantly abundant in the transgenic hairy root cultures grown under light conditions. Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) showed that the identified metabolites were separated far based on the primary and secondary metabolite contents present in the control and transgenic hairy root lines grown under light and dark conditions. Metabolic pathway analysis of the detected metabolites showed 54 pathways were identified, among these 30 were found to be affected. From these results, the AtMYB12 transcription factor activity might be light-responsive in the transgenic hairy root cultures, triggering the activation of the primary and secondary metabolic pathways in Korean mint