<i>Astraeus ryoocheoninii</i> sp. nov. from Korea and Japan and phylogenetic relationships within <i>Astraeus</i>

Ryoo, Rhim,Sou, Hong-duck,Park, Hyun,Ka, Kang-Hyeon 'Mycotaxon, Ltd.' 2017 Mycotaxon Vol.132 No.1

<P>The morphological characteristics of a collection by C.I. Ryoo and K.-H. Ka from the demilitarized zone (DMZ) of Korea, invalidly published as 'Astraeus koreana', are re-evaluated, described, and illustrated. Phylogenetic analysis using nrITS sequence data indicate that 'Astraeus koreana', an unnamed 'Japanese Astraeus group 2', and a Japanese specimen E0059827 all differ from A. hygrometricus var. koreanus and represent a new species, proposed here as Astraeus ryoocheoninii.</P>

Marasmioid and Gymnopoid Fungi of the Republic of Korea. 8. Gymnopus Section Levipedes

( Rhim Ryoo ),( Vladimír Antonín ),( Kang-hyeon Ka ) 한국균학회 2020 Mycobiology Vol.48 No.4

Collections of Gymnopus sect. Levipedes from the Republic of Korea have been studied. Two new species, Gymnopus dryophiloides and G. brunneodiscus, are described based on their macro- and micromorphological and phylogenetic characteristics. Three other species, referred to as Gymnopus spp. 1, 2, and 3, are distinguished as separate taxa without formal descriptions. Taxonomic and phylogenetic positions of all taxa have been inferred and confirmed by analyses of ITS and LSU sequence data. Their detailed descriptions, illustrations and an identification key are provided.

Antiviral activity against Influenza A (H1N1) virus of Oak mushroom (Lentinula edodes) Extract

Rhim Ryoo,Hyorim Lee,Mi-Jeong Park,Eunjin Kim,Ki Won Lee 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10

Oak mushroom (Lentinula edodes) have been recognized for helping to improve immunity in various oriental medicine libraries. However, this mushroom is vaguely known only as a healthy forest product without being clear on which pathogens this is effective against. Accordingly, in this study, we tried to evaluate the antiviral activity against viruses that cause human infection by using aqueous extract of oak mushroom. The material used in this study was the cultivar "Sanbaekhyang" developed and cultivated by the National Institute of Forest Science. For the antiviral activity test, the hot water extract of the mushroom was prepared by incubating 50g of the dried fruiting body powder in 500 ml of distilled water at 100°C for 2 hours. Antiviral efficacy evaluation was performed with the novel swine- origin influenza A (H1N1) virus by modified ASTM E1052- 11 method using plaque assay. As a result of measuring the decrement in the virus for 2 hours, this exctract showed 99.997% antiviral efficacy against the virus. This result indicated that the oak mushroom extract is highly valuable for use as a personalized food and pharmaceutical material for the prevention of respiratory pathogens.

Antiviral effect of Wild Oyster mushroom (Pleurorus ostereatus) against respiratory virus

Rhim Ryoo,Hyorim Lee,Mi-Jeong Park,Eunjin Kim,Ki Won Lee 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10

Oyster mushroom (Pleurorus ostereatus) is popular as a healthy diet food due to their richness in essential amino acids and low calories. Also, the need for functional research on disease prevention using this mushroom has been increased. Thus, our study tried to evaluate the antiviral activity against viruses that cause human infection by using hot water extract of oyster mushroom. The material used in this study was the fruiting bodies of this mushroom which were collected from Ginko biloba in Yongmunsa, Kapyung in 2018. For the antiviral activity test, the aqueous extract of the mushroom was prepared by incubating 50g of the dried fruiting body powder in 500 ml of distilled water at 100°C for 2 hours. Antiviral activity was performed with the novel swine-origin influenza A (H1N1) virus by modified ASTM E1052-11 method using plaque assay. As a result of measuring the decrements in the virus for 2 hours, this extract showed 99.99% antiviral efficacy against influenza A (H1N1) virus. This result suggest that the boiled oyster mushroom extract has a high application value for the prevention of viral respiratory diseases as a personalized food through drinking material in daily life.

Cultivation Characteristics of Lentinula edodes Strains using Oak Tree Log and Sawdust Blocks in the Republic of Korea

Rhim Ryoo,Eun-Jin Wang,Yeongseon Jang,Youngae Park,Kang-Hyeon Ka 한국버섯학회 2017 버섯 Vol.21 No.2

For centuries, Lentinula edodes called “Pyogo” in Korea has been cultivated as a high-grade edible mushroom in Asia. This is known as medicinal mushroom for cold prevention in oriental medicine. In the world market, this mushroom of Lentinula edodes is introduced as representative edible and medicinal mushroom in Asia. As consumer interest increases, Asian Lentinula edodes market is also growing. There is a record that Korea has already been used as a gourmet food on the royal meal table for the king in the 15th century Joseon Dynasty. In Korea's famous oriental book, it is cooked with many traditional foods because of the pharmaceutical efficacy of this mushroom. For long time ago, difference in cultivation as well as in mushroom growth of Lentinula edodes has studied in Korea. Recent advances in cultivation of selected high quality mushroom studied from substrate optimization using log and sawdust of oak tree. Cultivation of Lentinula edodes strain research controlled the production of large quantity of various substrate conditions. This mushroom mycelia and fruit-body were cultivated in log of oak tree and sawdust substrate cultivation in types of bioreactors. According to compared cultivation method, it presented the optimistic condition for the amount production of various Lentinula edodes strain in Korea.

단보 : 한국산 낙엽버섯류의 새로운 한국어 일반명 -1. 낙엽버섯속

류림 ( Rhim Ryoo ),블라드미르안토닌 ( Vladimir Antonin ),가강현 ( Kang Hyeon Ka ),신현동 ( Hyeon Dong Shin ) 한국균학회 2013 韓國菌學會誌 Vol.41 No.4

47 species was reported in the genus Marasmius in Republic of Korea up to now. 26 of total 47 species previously recorded from Korea were made up a list. Korean common names of 10 new species and 11 species newly recorded in Korea were introduced in study with synoptic key. These names were followed by the Romanization rule to express Korean common name.

한국산 낙엽버섯류의 기록

류림,신현동 고려대학교 2007 생명자원연구 Vol.15 No.-

Ginsenoside Rk1 is a novel inhibitor of NMDA receptors in cultured rat hippocampal neurons

Ryoo, Nayeon,Rahman, Md. Ataur,Hwang, Hongik,Ko, Sung Kwon,Nah, Seung-Yeol,Kim, Hyoung-Chun,Rhim, Hyewhon The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.3

Background: Ginsenoside Rk1, a saponin component isolated from heat-processed Panax ginseng Meyer, has been implicated in the regulation of antitumor and anti-inflammatory activities. Although our previous studies have demonstrated that ginsenoside Rg3 significantly attenuated the activation of NMDA receptors (NMDARs) in hippocampal neurons, the effects of ginsenosides Rg5 and Rk1, which are derived from heat-mediated dehydration of ginsenoside Rg3, on neuronal NMDARs have not yet been elucidated. Methods: We examined the regulation of NMDARs by ginsenosides Rg5 and Rk1 in cultured rat hippocampal neurons using fura-2-based calcium imaging and whole-cell patch-clamp recordings. Results: The results from our investigation showed that ginsenosides Rg3 and Rg5 inhibited NMDARs with similar potencies. However, ginsenoside Rk1 inhibited NMDARs most effectively among the five compounds (Rg3, Rg5, Rk1, Rg5/Rk1 mixture, and protopanaxadiol) tested in cultured hippocampal neurons. Its inhibition is independent of the NMDA- and glycine-binding sites, and its action seems to involve in an interaction with the polyamine-binding site of the NMDAR channel complex. Conclusion: Taken together, our results suggest that ginsenoside Rk1 might be a novel component contributable to the development of ginseng-based therapeutic treatments for neurodegenerative diseases.

Ginsenoside Rk1 is a novel inhibitor of NMDA receptors in cultured rat hippocampal neurons 490

Nayeon Ryoo,Md. Ataur Rahman,Hongik Hwang,Sung Kwon Ko,Seung-Yeol Nah,Hyoung-Chun Kim,Hyewhon Rhim 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.3

Background: Ginsenoside Rk1, a saponin component isolated from heat-processed Panax ginseng Meyer,has been implicated in the regulation of antitumor and anti-inflammatory activities. Although ourprevious studies have demonstrated that ginsenoside Rg3 significantly attenuated the activation ofNMDA receptors (NMDARs) in hippocampal neurons, the effects of ginsenosides Rg5 and Rk1, which arederived from heat-mediated dehydration of ginsenoside Rg3, on neuronal NMDARs have not yet beenelucidated. Methods: We examined the regulation of NMDARs by ginsenosides Rg5 and Rk1 in cultured rat hippocampalneurons using fura-2ebased calcium imaging and whole-cell patch-clamp recordings. Results: The results from our investigation showed that ginsenosides Rg3 and Rg5 inhibited NMDARswith similar potencies. However, ginsenoside Rk1 inhibited NMDARs most effectively among the fivecompounds (Rg3, Rg5, Rk1, Rg5/Rk1 mixture, and protopanaxadiol) tested in cultured hippocampalneurons. Its inhibition is independent of the NMDA- and glycine-binding sites, and its action seems toinvolve in an interaction with the polyamine-binding site of the NMDAR channel complex. Conclusion: Taken together, our results suggest that ginsenoside Rk1 might be a novel componentcontributable to the development of ginseng-based therapeutic treatments for neurodegenerativediseases.

Trichothecene and tremulane sesquiterpenes from a hallucinogenic mushroom Gymnopilus junonius and their cytotoxicity

Seulah Lee,Rhim Ryoo,Jin Hee Choi,Jeong‑Han Kim,Seon‑Hee Kim,Ki Hyun Kim 대한약학회 2020 Archives of Pharmacal Research Vol.43 No.2

Gymnopilus junonius (Fr.) P. D. Orton (Cortinariaceae)is a hallucinogenic mushroom, a well-knownpoisonous mushroom that is widely known as "big laughtermushroom" because it causes excessive laughter in thosewho consume it. Chemical investigation of G. junoniusfruiting bodies was performed, resulting in the isolationand structural identification of three sesquiterpenes (1−3),including a new trichothecene sesquiterpene (2) and a newtremulane sesquiterpene (3). Compound 1 was identifiedfrom G. junonius for the first time. The chemical structuresof the new compounds were established by detailed analysisof 1D and 2D (1H–1H correlated spectroscopy [COSY],heteronuclear single quantum coherence [HSQC], and heteronuclearmultiple-bond coherence [HMBC]) nuclear magneticresonance (NMR) spectra, and high-resolution massspectrometry (HRMS). In particular, the absolute configurationsof compounds 2 and 3 were unambiguously determinedby quantum chemical electronic circular dichroism (ECD)calculations. The isolated compounds (1−3) were evaluated for their cytotoxic effects on human lung and prostate cancercell lines where trichothecene sesquiterpenes (1 and 2)showed remarkable cytotoxicity similar to that of the controldrug, i.e., doxorubicin. Our findings provide experimentalevidence suggesting the potential anti-cancer effects of trichothecenesesquiterpenes from a poisonous mushroom.