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Yoshiteru Oshima - One of the best experts on this subject based on the ideXlab platform.
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Aromatic Polyketide Production in Cordyceps indigotica, an Entomopathogenic Fungus, Induced by Exposure to a Histone Deacetylase Inhibitor
Organic letters, 2012Co-Authors: Teigo Asai, Takashi Yamamoto, Yoshiteru OshimaAbstract:Cultivation of Cordyceps indigotica, an Entomopathogenic Fungus, in the presence of suberoyl bis-hydroxamic acid (an HDAC inhibitor) greatly activated its polyketide synthesis apparatus to afford six novel aromatic polyketides, indigotides C–F (1–4), 13-hydroxyindigotide A (5), and 8-O-methylindigotide B (6). The structures of these compounds were determined by NMR spectroscopic analyses. Among the compounds, indigotides C–E (1–3) possessed unprecedented dimeric polyketide frameworks possibly generated via a [4 + 2] cycloaddition or Michael type reaction.
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tenuipyrone a novel skeletal polyketide from the Entomopathogenic Fungus isaria tenuipes cultivated in the presence of epigenetic modifiers
Organic Letters, 2012Co-Authors: Teigo Asai, Yuming Chung, Tomoji Ozeki, Fang Rong Chang, Kouwa Yamashita, H Sakurai, Yoshiteru OshimaAbstract:The concomitant addition of the histone deacetylase inhibitor and the DNA methyltransferase inhibitor to the culture medium of an Entomopathogenic Fungus, Isaria tenuipes, greatly enhanced its secondary metabolite production and led to the isolation of tenuipyrone (1), a novel polyketide with an unprecedented tetracyclic ring system bearing a spiroketal structural component, along with two known C10-polyketides, cephalosporolide B (2), which is a plausible biosynthetic precursor of 1, and cephalosporolide F (3).
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Aromatic polyketide glycosides from an Entomopathogenic Fungus, Cordyceps indigotica
Tetrahedron Letters, 2012Co-Authors: Teigo Asai, Yuming Chung, Fang Rong Chang, Kouwa Yamashita, Takashi Yamamoto, Yoshiteru OshimaAbstract:Abstract A new aromatic polyketide glycoside, indigotide A ( 1 ), was isolated from the culture broth of the Entomopathogenic Fungus, Cordyceps indigotica , along with known cyclic depsipeptides, destruxins A, A 2 , B, B 2 and E ( 3 – 7 ), and a polyketide, NG-393 ( 8 ). Repeated treatment of the C . indigotica culture broth with 5-azacytidine, a DNA methyltransferase inhibitor, led to the isolation of another new aromatic polyketide glycoside, indigotide B ( 2 ).
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Novel trichothecanes, paecilomycine A, B, and C, isolated from Entomopathogenic Fungus, Paecilomyces tenuipes
Tetrahedron Letters, 2004Co-Authors: Haruhisa Kikuchi, Yasuhiro Miyagawa, Yuko Sahashi, Satoshi Inatomi, Asami Haganuma, Norimichi Nakahata, Yoshiteru OshimaAbstract:Paecilomycine A (1), B (2), and C (3) were isolated from cultivated fruiting bodies of Paecilomyces tenuipes (Isaria japonica), which is a popular Entomopathogenic Fungus used in folk medicine and health foods in China, Korea, and Japan. The structures of 1–3 were deduced from their spectroscopic data and their absolute configurations were elucidated by preparing their MPA esters. Compound 1 showed activity in the neurotrophic factor biosynthesis in glial cells.
Masahiko Isaka - One of the best experts on this subject based on the ideXlab platform.
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Isariotins E and F, spirocyclic and bicyclic hemiacetals from the Entomopathogenic Fungus Isaria tenuipes BCC 12625.
Journal of natural products, 2009Co-Authors: Taridaporn Bunyapaiboonsri, Seangaroon Yoiprommarat, Kamolphan Intereya, Pranee Rachtawee, Nigel L. Hywel-jones, Masahiko IsakaAbstract:New spirocyclic and bicyclic hemiacetals, isariotins E (1) and F (2), together with TK-57-164A (3) were isolated from the Entomopathogenic Fungus Isaria tenuipes BCC 12625. The absolute configurati...
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isariotins e and f spirocyclic and bicyclic hemiacetals from the Entomopathogenic Fungus isaria tenuipes bcc 12625
Journal of Natural Products, 2009Co-Authors: Taridaporn Bunyapaiboonsri, Seangaroon Yoiprommarat, Kamolphan Intereya, Pranee Rachtawee, Nigel L Hyweljones, Masahiko IsakaAbstract:New spirocyclic and bicyclic hemiacetals, isariotins E (1) and F (2), together with TK-57-164A (3) were isolated from the Entomopathogenic Fungus Isaria tenuipes BCC 12625. The absolute configuration of 3 was addressed by application of the modified Mosher’s method. Isariotin F (2) exhibited activity against the malaria parasite Plasmodium falciparum K1 with an IC50 value of 5.1 μM and cytotoxic activities against cancer cell lines (KB, BC, and NCI-H187) and nonmalignant (Vero) cells with respective IC50 values of 15.8, 2.4, 1.6, and 2.9 μM.
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An antimalarial tetrapeptide from the Entomopathogenic Fungus Hirsutella sp. BCC 1528.
Journal of natural products, 2006Co-Authors: Jiraporn Thongtan, Janya Saenboonrueng, Pranee Rachtawee, Masahiko IsakaAbstract:Hirsutellic acid A (1), a new linear tetrapeptide possessing an anthranilic acid residue at the C-terminus, was isolated from a fermentation broth of the Entomopathogenic Fungus Hirsutella sp. BCC 1528. The structure of this compound was elucidated by NMR and MS analyses, and its absolute configuration was deduced by HPLC analysis of the acid hydrolysate using a chiral column. Hirsutellic acid A exhibits activity against the malarial parasite Plasmodium falciparum K1 with an IC50 value of 8.0 μM, while it was noncytotoxic to Vero cells at a concentration of 95 μM.
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A cytotoxic xanthone dimer from the Entomopathogenic Fungus Aschersonia sp. BCC 8401.
Journal of natural products, 2005Co-Authors: Masahiko Isaka, Somporn Palasarn, Kanokarn Kocharin, Janya SaenboonruengAbstract:Ascherxanthone A (1), a novel symmetrical tetrahydroxanthone dimer, was isolated from the Entomopathogenic Fungus Aschersonia sp. BCC 8401. The structure of 1 was elucidated by spectroscopic analysis, especially 2D-NMR. Compound 1 exhibited activity against Plasmodium falciparum K1 with an IC(50) value of 0.20 microg/mL, but it also showed cytotoxic activities against Vero cells and three tumor cell lines.
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Enniatin production by the Entomopathogenic Fungus Verticillium hemipterigenum BCC 1449.
The Journal of antibiotics, 2004Co-Authors: Sumalee Supothina, Masahiko Isaka, Morakot Tanticharoen, Kanyawim Kirtikara, Yodhathai ThebtaranonthAbstract:Optimal fermentation conditions for enniatin production using the Entomopathogenic Fungus Verticillium hemipterigenum BCC 1449 have been investigated. Among various liquid media tested, highest efficiency of enniatin production was achieved by fermentation in yeast extract sucrose. Application of this condition to large-scale fermentation resulted in the isolation of three new analogs, O1, O2 and O3, which are closely related isomers that were characterized as an inseparable mixture, along with seven known enniatins.
Yodhathai Thebtaranonth - One of the best experts on this subject based on the ideXlab platform.
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Enniatin production by the Entomopathogenic Fungus Verticillium hemipterigenum BCC 1449.
The Journal of antibiotics, 2004Co-Authors: Sumalee Supothina, Masahiko Isaka, Morakot Tanticharoen, Kanyawim Kirtikara, Yodhathai ThebtaranonthAbstract:Optimal fermentation conditions for enniatin production using the Entomopathogenic Fungus Verticillium hemipterigenum BCC 1449 have been investigated. Among various liquid media tested, highest efficiency of enniatin production was achieved by fermentation in yeast extract sucrose. Application of this condition to large-scale fermentation resulted in the isolation of three new analogs, O1, O2 and O3, which are closely related isomers that were characterized as an inseparable mixture, along with seven known enniatins.
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New diketopiperazines from the Entomopathogenic Fungus Verticillium hemipterigenum BCC 1449.
The Journal of antibiotics, 2003Co-Authors: Chongdee Nilanonta, Prasat Kittakoop, Masahiko Isaka, Junya Saenboonrueng, Vatcharin Rukachaisirikul, Palangpon Kongsaeree, Yodhathai ThebtaranonthAbstract:Two new diketopiperazines, bisdethiodi (methylthio)-1-demethylhyalodendrin and 1-demethylhyalodendrin tetrasulfide, together with two known cyclodepsipeptides, enniatins B and B4, and two known pyrones, pyrenocines A and B, were isolated from a culture broth of the Entomopathogenic Fungus Verticillium hemipterigenum BCC 1449. These structures were elucidated using spectroscopic methods and X-ray crystallography. Antimalarial and cytotoxic activities of these compounds were evaluated.
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Hirsutellide A, a new antimycobacterial cyclohexadepsipeptide from the Entomopathogenic Fungus Hirsutella kobayasii.
Journal of Natural Products, 2002Co-Authors: Namphung Vongvanich, Prasat Kittakoop, Masahiko Isaka, Srisuda Trakulnaleamsai, Saovaluk Vimuttipong, Morakot Tanticharoen, Yodhathai ThebtaranonthAbstract:A new cyclohexadepsipeptide, named hirsutellide A (1), was isolated from a cell extract of the Entomopathogenic Fungus Hirsutella kobayasii BCC 1660. The structure of 1 was elucidated by analyses of spectroscopic data, and its absolute stereochemistry was addressed by the use of Marfey's method. Hirsutellide A (1) exhibited antimycobacterial and antimalarial activities, but was inactive toward the Vero cell line (at 50 μg/mL).
Teigo Asai - One of the best experts on this subject based on the ideXlab platform.
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Aromatic Polyketide Production in Cordyceps indigotica, an Entomopathogenic Fungus, Induced by Exposure to a Histone Deacetylase Inhibitor
Organic letters, 2012Co-Authors: Teigo Asai, Takashi Yamamoto, Yoshiteru OshimaAbstract:Cultivation of Cordyceps indigotica, an Entomopathogenic Fungus, in the presence of suberoyl bis-hydroxamic acid (an HDAC inhibitor) greatly activated its polyketide synthesis apparatus to afford six novel aromatic polyketides, indigotides C–F (1–4), 13-hydroxyindigotide A (5), and 8-O-methylindigotide B (6). The structures of these compounds were determined by NMR spectroscopic analyses. Among the compounds, indigotides C–E (1–3) possessed unprecedented dimeric polyketide frameworks possibly generated via a [4 + 2] cycloaddition or Michael type reaction.
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tenuipyrone a novel skeletal polyketide from the Entomopathogenic Fungus isaria tenuipes cultivated in the presence of epigenetic modifiers
Organic Letters, 2012Co-Authors: Teigo Asai, Yuming Chung, Tomoji Ozeki, Fang Rong Chang, Kouwa Yamashita, H Sakurai, Yoshiteru OshimaAbstract:The concomitant addition of the histone deacetylase inhibitor and the DNA methyltransferase inhibitor to the culture medium of an Entomopathogenic Fungus, Isaria tenuipes, greatly enhanced its secondary metabolite production and led to the isolation of tenuipyrone (1), a novel polyketide with an unprecedented tetracyclic ring system bearing a spiroketal structural component, along with two known C10-polyketides, cephalosporolide B (2), which is a plausible biosynthetic precursor of 1, and cephalosporolide F (3).
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Aromatic polyketide glycosides from an Entomopathogenic Fungus, Cordyceps indigotica
Tetrahedron Letters, 2012Co-Authors: Teigo Asai, Yuming Chung, Fang Rong Chang, Kouwa Yamashita, Takashi Yamamoto, Yoshiteru OshimaAbstract:Abstract A new aromatic polyketide glycoside, indigotide A ( 1 ), was isolated from the culture broth of the Entomopathogenic Fungus, Cordyceps indigotica , along with known cyclic depsipeptides, destruxins A, A 2 , B, B 2 and E ( 3 – 7 ), and a polyketide, NG-393 ( 8 ). Repeated treatment of the C . indigotica culture broth with 5-azacytidine, a DNA methyltransferase inhibitor, led to the isolation of another new aromatic polyketide glycoside, indigotide B ( 2 ).
Robert H. A. Coutts - One of the best experts on this subject based on the ideXlab platform.
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Identification and sequence determination of a novel double-stranded RNA mycovirus from the Entomopathogenic Fungus Beauveria bassiana
Archives of Virology, 2015Co-Authors: Ioly Kotta-loizou, Jana Sipkova, Robert H. A. CouttsAbstract:An isolate of the Entomopathogenic Fungus Beauveria bassiana was found to contain five double-stranded (ds) RNA elements ranging from 1.5 to more than 3 kbp. The complete sequence of the largest dsRNA element is described here. Analysis of the RdRp nucleotide sequence reveals its similarity to unclassified dsRNA elements, such as Alternaria longipes dsRNA virus 1, and its distant relationship to the RNA-dependent RNA polymerases of members of the family Partitiviridae .