• Korean Journal of Plant Resources
• /
• v.19 no.1
• /
• pp.189-195
• /
• 2006

We investigated the genetic variation in Stewartia koreana Nakai by examining 61 I-SSR amplicons in 120 individuals distributed among six natural populations in Korea. The overall percentage of polymorphic I-SSR amplicons was 81.9% and mean number of amplicons per I-SSR primer was 12.2. Levels of genetic diversity within 6 populations were similar each other[Shannon's Index $0.358{\sim}0.467$(mean: 0.407)]. The Mt. Obong population had the highest level of genetic diversity and was most distinctive from the other populations. Most variation existed among individuals within population(88.2%). Genetic differentiation among populations(${\phi}_{ST}$) was 0.118. The UPGMA dendrogram based on the genetic distance failed in showing decisive geographic relationships.

• Journal of Life Science
• /
• v.28 no.5
• /
• pp.509-516
• /
• 2018

Five phenolic compounds were isolated from the ethyl acetate fraction of leaves from Stewartia koreana, and their nitric-oxide (NO) inhibitory activities were measured to identify the major active constituents responsible for the efficacy of the extract against inflammatory reactions. These five compounds were quercetin (1), quercitrin (2), hyperin (3), quercetin-3-O-(6"-O-galloyl)-${\beta}$-D-galactopyranoside (4), and kaempferol 3-O-[2",6"-di-O-(trans-p-coumaroyl)]-${\beta}$-D-glucopyranoside (5). Among the separated compounds in the EtOAc fraction, compounds 4 and 5 were isolated for the first time, and no study has yet reported their anti-inflammatory effects. The compounds were identified by spectroscopic analysis, and the isolated compounds showed significant NO inhibitory effects in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Compound 5 showed the most potent inhibitory effect (63.35% inhibition) against LPS-induced NO production compared to that of compound 1 (17.17%), compound 2 (5.0%), compound 3 (3.92%), and compound 4 (6.32%) at $10{\mu}g/ml$ concentration. NO production was inhibited by suppressing the protein expression of inducible nitric-oxide synthase in LPS-stimulated RAW 264.7 macrophages. These results indicate that kaempferol 3-O-[2",6"-di-O-(trans-p-coumaroyl)]-${\beta}$-D-glucopyranoside might be the major active compound responsible for the anti-inflammatory effects of S. koreana.

• Korean Journal of Plant Resources
• /
• v.17 no.3
• /
• pp.272-277
• /
• 2004

Zygotic embryos of Stewartia korean Nakai were cultured to determine the effects both of BA and NAA on adventitious shoot induction. Multiple shoots (about 11 per explant) were formed when the embryos were treated with 1.0 mg/L BA alone. On the other hand, NAA appeared to inhibit shoot induction when treated with BA. Adventitious shoots looked differ in form and color by the combinations of BA and NAA treated. When both BA and NAA were present, the shoots became short and developed dark color. The highest rooting was observed at 0.5mg/L NAA. The results could be useful for the establishment of in vitro regeneration system for Stewartia koreana Nakai.

• Journal of the Korean Chemical Society
• /
• v.67 no.2
• /
• pp.129-136
• /
• 2023

Osteoarthritis is to the abnormality of the inflammatory response of joint tissue caused by various causes such as aging, and muscle loss. In this study, the activity in joint inflammation was verified using SKBE, a plant extract, and the expression levels of arthritis-inducing proteins including MMP-1, MMP-3, MMP-13, and collagen type II in vitro were compared and analyzed. Furthermore, we synthesized α-spinasterol, an active ingredient of SKBE, by the previously reported synthesis method and these findings could provide a new starting point for the development of treatments for osteoarthritis.

• Journal of Life Science
• /
• v.33 no.11
• /
• pp.936-943
• /
• 2023

This study was conducted to investigate the potential of Stewartia koreana as anti-microbial materials. The branches, stems and leaves of S. koreana were extracted into 70% ethanol and their antibacterial activity against P. aeruginosa was confirmed. The leaf, branch and stems extracts (1 mg/disc) showed the antibacterial activity against P. aeruginosa and leaf extracts showed higher antibacterial activities than those from branch extracts. The MIC against P. aeruginosa was 0.8 mg/ml and showed bacteriostatic action. The inhibitory effects of extract on biofilm formation and gene expression related to biofilm formation of P. aeruginosa was determined by biofilm biomass staining, SEM and qRT-PCR analysis. The biofilm biomass and cell growth of P. aeruginosa in the cultures treated with 0.2~2.0 mg/ml of S. koreana leaf extracts were significantly decreased in a concentration-dependent manner. We observed that the extract had an inhibitory effect on the formation of P. aeruginosa biofilms at concentrations of 0.8 mg/ml by SEM. qRT-PCR analysis showed that the lasI and rh1I gene expression associated to quorum sensing (QS) in the cultures treated with 0.2~2.0 mg/ml of S. koreana leaf extracts were suppressed in a concentration-dependent manner. Based on the above results, it can be concluded that S. koreana leaf extracts can be used as anti-microbial material derived from natural materials, as demonstrated by the antibacterial action and inhibition of biofilm formation of P. aeruginosa by QS inhibition.

• Korean Journal of Plant Tissue Culture
• /
• v.22 no.2
• /
• pp.77-81
• /
• 1995

When cultured on MS medium supplemented with 0.5 mg/L NAA alone or 1.0 mg/L 2,4-D and 0.5 mg/L BA, immature zygotic embryos of Stewartia koreana formed embryogenic calli and somatic embryos. In investigate effect of sucrose concentration on somatic embryo development, embryogenic calli were transferred to MS basal medium containing 1.5,3, 6 or 9% sucrose. The greatest frequency of somatic embryos was obtained on medium containing 6% sucrose. However addition of 1.5 or 9% sucrose to medium inhibited somatic embryo germination and development into normal plantlet After 5 weeks of hardening culture on medium containing 6% sucrose, somatic embryos were transferred to half strangth MS medium supplemented with 0.1% charcol, wherein these embryo developed into the normal plantlets.

• Journal of Life Science
• /
• v.32 no.1
• /
• pp.56-62
• /
• 2022

This study was investigated to evaluate the potential of Stewartia koreana Nakai as an oral healthcare material. The inhibitory effects of extracts on the biofilm formation and fimbriae genes expression of Porphyromonas gingivalis were determined by minimal inhibitory concentrations (MIC), biofilm biomass staining, SEM, and qRT-PCR analysis. The S. koreana Nakai branch was extracted into 70% ethanol, and bacteriostatic MIC of extracts against P. gingivalis were 0.6 mg/ml. In P. gingivalis cultures treated with 0.2-2.0 mg/ml of extract, biofilm production rate was significantly decreased in a concentration-dependent manner. The morphology of treated and untreated samples was observed by SEM, and cell aggregation and biofilm were only observed in those treated with extract. Subsequently, qRT-PCR analysis showed that the mRNA expression on fimbriae genes fimA and fimB was suppressed in a concentration-dependent manner. Based on these results, it can be suggested that S. koreana branch extract has the potential to be used as naturally derived oral healthcare material because of its bacteriostatic action and inhibition of P. gingivalis biofilm formation.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.13 no.4
• /
• pp.18-29
• /
• 2010

The vascular plants in ecological forest site on the Gujaebong (Mt.), Hadong were listed 338 taxa; 85 families, 219 genera, 290 species, 1 subspecies, 40 varieties and 7 forms. Divided into 338 taxa; woody plants were 121 taxa (35.8%) and herbaceous plants were 217 taxa (64.2%). Based on the legal protection species, endangered wild plants II were recorded; Aconitum austro-koreense, Corylopsis gotoana var. coreana and rare plants (IUCN) by the Korea Forest Service and Korea National Arboretum 5 taxa were recorded; Botrychium virginianum, Aconitum austro-koreense, Coreanomecon hylomecoides, Corylopsis gotoana var. coreana, Viola albida. Based on the list of Korean endemic plants, 13 taxa were recorded; Cephalotaxus koreana, Thalictrum actaefolium, Vicia nipponica, Indigofera koreana, Stewartia koreana, Weigela subsessilis, etc. Based on the list of approved for delivering overseas of plants, 5 taxa were recorded; Coreanomecon hylomecoides, Vaccinium oldhami, Paulownia coreana, Asperula lasiantha, Carex okamotoi. Specific plant species by floral region were total 21 taxa (6.2% of all 338 taxa of vascular plants); Aconitum austro-koreense, Corylopsis gotoana var. coreana in class V, Cimicifuga heracleifolia, Coreanomecon hylomecoides in class IV, 4 taxa (Stewartia koreana, Phacellanthus tubiflorus, Lonicera subhispida, etc.) in class III, Potentilla dickinsii, Viola orientalis in class II, 11 taxa (Aconitum jaluense, Angelica anomala, Erythronium japonicum, etc.) in class I. The naturalized plants in the surveyed sites were 8 families, 15 genera, 15 taxa (Phytolacca americana, Crassocephalum crepidioides, Lolium perenne, etc.) and naturalization rate was 4.4% of all 338 taxa of vascular plants.

• Journal of Environmental Science International
• /
• v.16 no.10
• /
• pp.1139-1146
• /
• 2007

The vascular plants in the Mt. Manduk was listed 560 taxa composed of 110 families, 345 genera, 488 species, 1 subspecies, 67 varieties and 4 forms. Based on the list of the rare plants by the Forest Research Institute, 4 taxa were recorded in the studied areas; Lilium distichum (Preservation priority order; No. 159), Tricyrtis dilatata (No. 97), Aristolochia contorta (No. 151) and Prunus yedoensis (No. 110). Based on the list of Korean endemic plants, 12 taxa were recorded; Cephalotaxus koreana, Carex okamotoi, Lilium amabile, Populus tomentiglandulosa, Salix purpurea var. japonica, Pseudostellaria multiflora, Prunus yedoensis, Stewartia koreana, Forsythia koreana, Paulownia core ana, Weigela subsessilis and Aster koraiensis. Based on the list of approved for delivering overseas of plants, 7 taxa were recorded; Carex okamotoi, Lilium distichum, Aristolochia contorta, Vaccinium oldhami, Paulownia coreana, Asperula lasiantha and Saussurea seoulensis. Specific plants by floral region were total 32 taxa; Prunus yedoensis in class V, Wistaria floribunda in class IV, 5 taxa (Girardinia cuspidata, Spiraea salicifolia, Acer palmatum, Stewartia koreana, Asperula lasiantha) in class III, 3 taxa (Potentilla dickinsii, Viola tokubuchiana var. takedana and Caryopteris incana) in class II and 22 taxa (Pinus koraiensis, Hosta capitata, Chloranthus japonicus, Salix glandulosa, Juglans mandshurica, etc.) in class I. The naturalized plants in the surveyed sites were 14 families, 36 genera, 44 species, 2 varieties, 46 taxa and naturalization rate was 8.2% of all 560 taxa of vascular plants. Wild plants disturbing ecosystem like Ambrosia artemisiifolia var. elatior have been increasing. Therefore, continuous control and conservation measures are needed on the ecosystem of Mt. Manduk.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2003.04a
• /
• pp.120-120
• /
• 2003