• Korean Journal of Plant Resources
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• v.30 no.6
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• pp.618-622
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• 2017

Various bioactive substances are found in Loranthus tanakae, including quercetin 3-rhamnoside (1), kaempferol 3-rhamnoside (2), rhamnetin 3-rhamnoside (3), and rhamnocitrin 3-rhamnoside (4), which inhibit tyrosinase. These compounds are mainly found in the EtOAc fraction of L. tanakae extract and demonstrate higher rates of tyrosinase inhibition than ascorbic acid, which was used as a control. Our results suggest that L. tanakae extracts can be utilized in skin whitening cosmetics.

• Archives of Pharmacal Research
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• v.27 no.1
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• pp.44-47
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• 2004

Loranthus tanakae Fr. et Sav. (Loranthaceae) is a species of mistletoe, a semiparasitic plant growing on the branches of Quercus and Betula species as host trees. In our ongoing search for bioactive compounds from endemic species in Korea, we have investigated to isolate the chemical constituents responsible for the antitumor effect of the MeOH extract of L. tanakae. The ethyl acetate soluble part of the MeOH extract demonstrated a marginal inhibition on the proliferation of the tumor cell lines such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system), and HCT-15 (colon) in vitro. Thus, the activity-guided isolation procedure upon the ethyl acetate soluble part of the extract has been carried out and finally four flavonoid rhamnopyranosides (1-4) were isolated as active principle. The structures of 1-4 were elucidated by the physicochemical and spectral data as rhamnetin 3-O-$\alpha$-L-rhamnoside (1), quercetin 3-O-$\alpha$-L-rhamnoside (2), rhamnocitrin 3-O-$\alpha$rhamnoside (3), and kaempferol 3-O-$\alpha$-L-rhamnoside (4).

• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.871-877
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• 2010

This study was conducted to investigate the effects of host tree species, temperature and humidity on ex vitro for seed germination in endangered species of Loranthus tanakae. In addition, we compared seed shapes between Loranthus tanakae and Viscum album that we could have easily shown in ex vitro condition. Seeds were germinated after one week inoculation and followed to develop radicles. Seed germination rates of Loranthus tanakae were 80~95% in most of the experimental conditions. The highest rate of holdfast penetrated to host plants was 72% in Populus alba var. pyramidalis among 13 different species tested at $20^{\circ}C$. Also the rates of their penetration were 57% in Morus bombycis, 55% in Acer palmatum and 42% in Castanea crenata at $20^{\circ}C$. Seeds were germinated under condition without irrigation and followed to withered in 12 weeks later. Stages of seed germination of the Loranthus tanakae were followed by radicle induction, holdfast development, haustorium formation and penetration in order in total period of 14 weeks.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.441-448
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• 2011

The objective of this study was to clarify the distribution, host preference and habitat characterstics of the endangered mistletoe species, Loranthus tanakae in Korea. Seven sites were selected for sampling in Gangwon Province, located in middle of Korea. Parameters including DBH, attached height, twig death, and the number of L. tanakae and Viscum album var. coloratum per tree for all infected individuals were investigated. One thousand, two hundred and seventy L. tanakae plants were found on the 420 host trees with 665 V. album var. coloratum on 227 of the trees. The infested host trees belonged to eight species and one variety species from six genera and five families. The highest percentage (86.9%) of individuals of L. tanakae were growing on Fagaceae. The infected trees occurred between altitudes of 420 m and 1,250 m above the sea level, but most of them were between 600 m and 900 m. The mean DBH and heights of parasitism were 38.6 cm and 13.0 m, respectively. Twig death was also observed on 300 host trees (71.4%) and 1.5 twig per tree. Most of the populations and the distribution of L. tanakae were highly affected by DBH out of some individual tree characteristics.

• Journal of Applied Biological Chemistry
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• v.62 no.1
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• pp.7-10
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• 2019

The whole plants of Loranthus tanakae were repeatedly extracted with 80% aqueous MeOH and the concentrate was partitioned into ethyl acetate (EtOAc), n-butyl alcohol (n-BuOH) and $H_2O$ fractions. The repeated silica gel ($SiO_2$), octadecyl $SiO_2$ (ODS), and Sephadex LH-20 column chromatographies for the n-BuOH fraction led to isolation of a cyclofarnesane sesquiterpene glucoside. The chemical structure including stereo structure was determined to be a (1'R,3'S,5'R,8'S,2E,4E)-dihydrophaseic acid $3^{\prime}-O-{\beta}-{\text\tiny{D}}$-glucopyranoside on the basis of spectroscopic analyses. This compound was isolated for the first time from L. tanakae in this study. Compound 1 showed a moderate dose-dependent cytotoxicity against human Caucasian gastric adenocarcinoma cells and human hepatocyte cari-noma cells cell lines at higher than $50{\mu}g/mL$.

• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.618-624
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• 2010

This study was conducted to establish the in vitro seed germination of Loranthus tanakae. A factorial experiment evaluated the effects of seed storage duration (0, 8, 16 weeks), media (MS, SH, White, WPM), presence of viscin, GA3, gelling agent and concentrations. Seed germinated after one week culture in in vitro condition and produced radicles. In vitro seed germination was optimal when the seeds removed viscin placed on SH medium (69%) and the addition of 0.35% gelrite (75%) in the same medium. As seed storage duration was expanded to 8 or 16 weeks, in vitro seed germination rate was reduced rapidly. Holdfasts were also produced at the side of radicles. The important factors to produce holdfast and haustorium was kind of media as an optimal condition in White medium without any supplements to be shown 98% and 8% respectively. Process of in vitro germination of Loranthus tanakae was followed to radicle elongation, holdfast development and then haustorium formation sequencially.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.428-436
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• 2013

To obtain biological basic data for the conservation strategies establishment of a rare mistletoe species, Loranthus tanakae(Loranthaceae) in Korea, the distribution range, habitat characteristics and an assessment of the conservation status on the natural populations of L. tanakae were investigated. As a result, the natural populations of L. tanakae were distributed in Bakdudaegan from Mt. Chiri to Mt Seorak in Korea penninsula, and 97.8% of surveyed individuals of the mistletoe species were found in Gangwon province. In natural populations, 1,385 individuals of L. tanakae were parasitic on 480 host trees, and distributed in sunshiny ridges of mountains of altitude range of 353 m to 1,250 m. The range of host trees of L. tanakae were composed of 5 families, 6 genera, 9 species, 1 subspecies, and of these, Quercus mongolica was preferred with 81.5% (389 trees among 480 host trees). As a result of assessing the conservation status through IUCN, L. tanakae was evaluated as Vulnerable (VU). It was considered that Mt. Seorak, Mt. Taegi and Mt. Odae population as habitats with the highest density of distribution of natural populations of L. tanakae should be designated as the protected areas. Thus, conservation strategies and related methods of the natural populations of L. tanakae were also discussed for the sustainable conservation.

• Korean Journal of Plant Taxonomy
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• v.48 no.4
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• pp.357-362
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• 2018

References in the modern Korean literature in this area to the Korean medicinal plant name written in Chinese script and expressed as Sanggisaeng have been extremely confusing. This name has been considered as six species, specifically Loranthus parasiticus, Loranthus tanakae, Taxillus yadoriki, Taxillus chinensis, Korthalsella japonica, and Viscum album var. coloratum. Recently, it was suggested that sanggisaeng is not distributed in Korea; however, the plant name Sanggisaeng recorded in old Korean literature sources, such as in the Hyang-yak-chae-chwi-wol-lyeong, Hyang-yak-jib-seong-bang, and Dong-ui-bo-gam sources, among others, was identified using the name V. album var. coloratum, whereas in China, Sanggisaeng was referred to as T. sutchuenensis. The Hangeul name of Sanggisaeng had been Ppongnamugyeousali, but now the name Gyeousali is widely used.

• Journal of Korean Society of Forest Science
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• v.104 no.1
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• pp.50-59
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• 2015

We investigated seasonal variation in photosynthetic characteristics and chlorophyll content of the Loranthus tanakae, Viscum album var. coloratum and its hosts in Korea. The maximum photosynthesis and transpiration rate of L. tanakae were $9.36{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at $941{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR (photosynthetically active radiation) in June, $5.06{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at $1,596{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR in July, respectively. The maximum photosynthesis and transpiration rate of V. album var. coloratum were $6.51{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at $418{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR in Autumn, $3.91{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at $1,735{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR in Autumn, respectively. V. album var. coloratum was able to conduct photosynthesis in November whereas its host and L. tanakae were not able to conduct photosynthesis. Especially transpiration rate of L. tanakae were always higher than its host and V. album var. coloratum. The chlorophyll a+b contents of L. tanakae was $8.23mg{\cdot}g^{-1}$ in July, V. album var. coloratum was $10.27mg{\cdot}g^{-1}$ in June, and chlorophyll a/b ratio of L. tanakae was 1.7~3.7, V. album var. coloratum was 1.1~4.5, depend on season.

• Korean Journal of Plant Resources
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• v.27 no.3
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• pp.263-270
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• 2014

Loranthus tanakae (Franch. & Sav.) is an endangered species of mistletoe, distributed in Korean peninsula. The objective of our research is to determine the effect of storage duration and conditions [air flow (AF) and air tight (AT)] at different temperatures for survivability and germination of mistletoe seeds, and also to monitor the effect of seed scarification on germination in vitro. The result revealed that the seeds stored in natural conditions (no stratification) showed highest survival rate of 100% and retained up to 93.3% even after two months of storage in natural conditions and showed higher germination percentage (90%) compare to after ripened seeds. However, the seed stored at $0^{\circ}C$ decreased the germination percentage (ranged from 63 to 73%). Therefore, it can be confirmed that mistletoe does not need after ripened treatment to promote germination. Our research also showed that the storage of L. tanaka seeds in freezing temperatures of $-20^{\circ}C$ and in room temperature for long time either in AT or AF conditions caused the loss of survival and germination rate. On the other hand, the chemical scarification (0.01N HCl incubation for 12 hrs. at $38^{\circ}C$) method was proven more effective to enhance germination percentage of L. tanakae. Regarding the temperature regime, $22^{\circ}C$ showed early germination of mistletoe seeds in vitro.