Identification, In Silico Characterization, and Differential Expression Profiles of Carotenoid, Xanthophyll, Apocarotenoid Biosynthetic Pathways Genes, and Analysis of Carotenoid and Xanthophyll Accumulation in Heracleum moellendorffii 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.

Verification of the Field Productivity and Bioequivalence of a Medicinal Plant (Polygonum multiflorum) Developed Using an In Vitro Culture Method.

Polygonum multiflorum Thunb. is a perennial plant that belongs to Polygonaceae. Root tissues are the main plant parts used as medicinal herbs in Korean oriental medicine. The P. multiflorum tuber is well known for its medicinal properties in Korean oriental medicine, and it contains a number of useful substances (secondary metabolites of emodin, 2,3,5,4'-tetrahydroxystilbene-2-O-ß-d-glucoside (TSG), etc.) that are increasing in demand, as several studies show that they have beneficial effects on the human body. In this study, the production volumes and useful material content differences between cultured P. multiflorum seedlings (culture seedlings: CSs), which had been grown using a tissue culture technique under optimized conditions, and existing varieties in circulation (seed seedlings: SSs) were determined using a long-term field test. The growth characteristics of the underground parts were investigated by harvesting the tuberous roots (medicinal parts) after 1 year, and the results showed that the fresh and dry weights of the CS tubers were higher than those of the SS tubers. However, the SS rootlets had higher fresh and dry weights than the CS rootlets. A liquid chromatography-mass spectrometry component analysis of the P. multiflorum tubers and a Fourier transform near-infrared spectrophotometer analysis of the roots were undertaken. The results showed that the levels of TSG, which is a medicinal substance produced by P. multiflorum, were higher in the CSs than in the SSs, but the differences were not significant. The CS results from this study will inform future studies on the mass production of P. multiflorum in the field because the medicinal area was greater in CSs than in SSs.

The Characteristics of the Growth and the Active Compounds of Angelica gigas Nakai in Cultivation Sites.

The active compounds of medicinal plants vary in composition and content depending on environmental factors, such as light, temperature, and soil. According to the Korean Pharmacopoeia standards for herbal medicine, the sum of nodakenin, decursin, and decursinolangelate, which are the marker components of Korean Angelica, should be at least 6.0 g/100 g. However, the content of the components in Korean Angelica cultivated in South Korea often fall below 6.0 g/100 g, due to weather conditions and cultivation site characteristics. This study aimed to gather information about environmental factors that affect the root growth and the content of active compounds. In total, 18 cultivation sites in Pyeongchang, Jecheon, and Bonghwa regions in Korea were investigated for this study. Environmental factors, such as the monthly mean temperature, mean relative humidity, duration of sunshine, total precipitation, soil acidity, and the characteristics of soil nutrient, were investigated over the growing season from April to October 2017. As for the growth characteristics, the dry weight of roots of Korean Angelica was measured. The sum of the contents of the three active compounds was 5.3-7.0 g/100 g and the nodakenin content was 0.3-1.3 g/100 g in the cultivation sites. This study concludes that the root yields in the cultivation sites would be improved if weather conditions are maintained with similar levels as those in their natural habitats. Additionally, the environment that improves root growth did not increase the content of active compounds; however, when there was a lot of gravel or high temperatures during the growth period, the content of active compounds was relatively high.

Verification of the Field Productivity of Rehmannia glutinosa (Gaertn.) DC. Developed Through Optimized In Vitro Culture Method.

Rehmannia glutinosa (Gaertn.) DC is a perennial plant belonging to the family Scropulariidae. The root of R. glutinosa is used in oriental medicine and mainly grown using rootstock rather than seed cultivation, which gives rise to several problems including root rot, and results in a low productivity and poor quality. To solve the challenges involved in R. glutinosa seed cultivation, our team previously used the formative features and genetic analysis of R. glutinosa to determine the optimal in vitro tissue culture conditions for producing sterile culture seedlings and rootstocks of R. glutinosa. The aim of the present study was to identify differences between R. glutinosa standard rootstock seedlings (SR), R. glutinosa culture rootstock seedlings (CR), and culture seedlings (CS) under field conditions. The reproductive characteristics of the aerial part were more robust while the area and length of leaves were smaller for SR than those for CR and CS. The characteristic that differed the most in SR was flowering, which did not occur in CR and CS. In addition, the fresh and dry weights of the subterranean parts of CR and CS were two-fold greater than those of SR. Fourier transform near-infrared (FT-NIR) analysis showed only slight differences between the chemical constituents of SR and its culture products, which was confirmed by measuring the content of catalpol, an indexing substance. Catalpol had a reduced content in the culture products compared to SR. However, this difference was not significant. Our findings will be useful for the identification of the best seedling type of R. glutinosa to enable its mass production.