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.

As the national flower of Korea, the Hibiscus syriacus L. (Rose of Sharon) is symbolic in its abundance and is a prominent feature of Korean culture. H. syriacus has played an important role in Korea, not only as an ornamental plant but also as an essential ingredient in folk remedies through its various parts. This study aimed to characterize the nutritional and biochemical composition of each plant unit of H. syriacus “Wonhwa.” The units are namely: the petals, leaves, roots, and sprouts from its seeds. According to the results each unit produced, the sprouts had the highest content of amino acids and fatty acids which adhere to the requirements of nutritionally excellent food ingredients. The petals produced high quantities of glucose, sucrose, and fumaric acid, with the highest antioxidant activity among the four units. The main bioactive compounds detected in H. syriacus extracts in the four units were o‐coumaric acid, p‐coumaric acid, schaftoside, isoschaftoside, apigenin‐6‐C‐glucoside‐7‐o‐glucoside, and kaempferol‐3‐O‐galactoside‐7‐O‐rhamnoside. Overall, the highest number of bioactive compounds, 2 phenolic acids and 22 flavonoids, were identified in the petals. These results suggest the possibility of excellent pharmacological activity in the petals.

Hibiscus sabdariffa L., (roselle) in the Malvaceae family is an erect subshrub known to be native to India and Malaysia. It is widely used as a food or tea material around the world, and its therapeutic effects have been widely studied. In this study, the sequencing of the complete chloroplast genome of H. sabdariffa was carried out. The result indicates a genome size of 162,428 bp, which is composed of a large single copy of 90,327 bp, two inverted repeats of 26,242 bp each, and a small single copy of 19,617 bp. Overall, a total of 131 genes were predicted, including 86 coding sequences, 37 tRNAs, and 8 rRNAs. According to a phylogenic analysis, it was clearly distinguished from outgroups such as other species of the genus Hibiscus used in the analysis.

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.

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-β-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.

In this study, we evaluated whether extracts of the roots of Hibiscus syriacus (HSR) exert immune activation activities and elucidated its potential mechanism in macrophages. The HSR dose-dependently increased the production of immunomodulators such as nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), and tumor necrosis factor (TNF-α) activated phagocytosis in macrophages. Inhibition of toll-like receptors 4 (TLR4) reduced the production of immunomodulators induced by HSR. Inhibition of mitogen-activated protein kinase (MAPKs), nuclear factor-κB (NF-κB) and phosphoinositide-3 kinase (PI3K) signaling attenuated the production of immunomodulators induced by HSR. Based on the results of this study, HSR was thought to activate macrophages through the production of immunomodulators and phagocytosis activation through TLR4-dependent MAPKs, NF-κB and PI3K signaling pathways. Therefore, it is thought that the HSR has the potential to be used as agents for enhancing immunity.