著者

Atsushi Ishihara Hiroaki Ohfuji

出版者

Japan Association of Mineralogical Sciences

雑誌

Journal of Mineralogical and Petrological Sciences (ISSN:13456296)

巻号頁・発行日

pp.230327, (Released:2023-10-13)

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In this study, we investigated the origin and formation process of zeolitized gastropod fossils in Neogene sediments (Shiote Formation) in Minamisoma, Fukushima, Japan using powder X-ray diffraction, SEM-EDS and micro-Raman spectroscopic analysis. The formation of zeolites was particularly pronounced in the upper chamber, which was not filled with detrital particles, of the gastropod fossils, where tabular crystals of heulandite were observed growing directly from the shell wall. The heulandite crystals are often covered by large euhedral crystals of calcite and occasionally by acicular crystals of mordenite. The formation of zeolite (heulandite) was also observed in the matrix of the host sandstone together with clay minerals (mostly montmorillonite), suggesting that the Shiote Formation experienced moderate metamorphism equivalent to zeolite facies during burial diagenesis. The Si/Al ratio of heulandite was found to decrease gradually from the bottom (∼4.5) to the top (∼3.1) within single crystals across the threshold (4.0) for clinoptilolite/heulandite classification boundary. This may reflect the increase in temperature of the surrounding environment with increase in the burial depth. The extensive growth of zeolites and calcite inside the gastropod fossils indicates that the shell provided semi-closed spaces in which pore fluid could be retained and condensed during diagenesis, thus promoting the crystal growth from the supersaturated solution.

著者

Atsushi Ishihara Kana Ando Anna Yoshioka Koichi Murata Yu Kokubo Noriko Morimoto Naoki Ube Yukinori Yabuta Makoto Ueno Shin-ichi Tebayashi Kotomi Ueno Kumiko Osaki-Oka

出版者

Pesticide Science Society of Japan

雑誌

Journal of Pesticide Science (ISSN:1348589X)

巻号頁・発行日

vol.44, no.2, pp.89-96, 2019-05-20 (Released:2019-05-20)

参考文献数

36

被引用文献数

10

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We investigated the effect of treatment with hot water extracts from the spent mushroom substrates (SMSs) of Lentinula edodes and Hypsizygus marmoreus on the resistance of rice leaves to Pyricularia oryzae infection. The spraying of the SMS extracts clearly suppressed the development of lesions caused by Py. oryzae infection. The accumulation of phytoalexins momilactones A and B, oryzalexin A, and sakuranetin was markedly induced by the spraying of extracts. The enhanced expression of defense related genes PR1b and PBZ was also found in leaves sprayed with the extracts. Treatments with the extracts also affected phytohormone levels. The levels of N6-(Δ2-isopentenyl)adenine and trans-zeatin markedly increased in response to treatment, whereas the levels of salicylic and jasmonic acids were largely unchanged.

著者

Atsushi ISHIHARA Hiroaki OHFUJI

出版者

Japan Association of Mineralogical Sciences

雑誌

Journal of Mineralogical and Petrological Sciences (ISSN:13456296)

巻号頁・発行日

vol.118, no.1, pp.230327, 2023 (Released:2023-11-21)

参考文献数

34

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In this study, we investigated the origin and formation process of zeolitized gastropod fossils in Neogene sediments (Shiote Formation) in Minamisoma, Fukushima, Japan using powder X-ray diffraction, SEM-EDS and micro-Raman spectroscopic analysis. The formation of zeolites was particularly pronounced in the upper chamber, which was not filled with detrital particles, of the gastropod fossils, where tabular crystals of heulandite were observed growing directly from the shell wall. The heulandite crystals are often covered by large euhedral crystals of calcite and occasionally by acicular crystals of mordenite. The formation of zeolite (heulandite) was also observed in the matrix of the host sandstone together with clay minerals (mostly montmorillonite), suggesting that the Shiote Formation experienced moderate metamorphism equivalent to zeolite facies during burial diagenesis. The Si/Al ratio of heulandite was found to decrease gradually from the bottom (∼ 4.5) to the top (∼ 3.1) within single crystals across the threshold (4.0) for clinoptilolite/heulandite classification boundary. This may reflect the increase in temperature of the surrounding environment with increase in the burial depth. The extensive growth of zeolites and calcite inside the gastropod fossils indicates that the shell provided semi-closed spaces in which pore fluid could be retained and condensed during diagenesis, thus promoting the crystal growth from the supersaturated solution.

著者

Atsushi Ishihara

出版者

Pesticide Science Society of Japan

雑誌

Journal of Pesticide Science (ISSN:1348589X)

巻号頁・発行日

vol.46, no.4, pp.382-392, 2021-11-20 (Released:2021-11-20)

参考文献数

79

被引用文献数

7

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Plants synthesize and accumulate a wide variety of compounds called secondary metabolites. Secondary metabolites serve as chemical barriers to protect plants from pathogens and herbivores. Antimicrobial secondary metabolites are accumulated to prevent pathogen infection. These metabolites are classified into phytoalexins (induced in response to pathogen attack) and phytoanticipins (present prior to pathogen infection). The antimicrobial compounds in the grass family (Poaceae) were studied from the viewpoint of evolution. The studies were performed at three hierarchies, families, genera, and species and include the following: 1) the distribution of benzoxazinoids (Bxs) in the grass family, 2) evolutionary replacement of phytoanticipins from Bxs to hydroxycinnamic acid amide dimers in the genus Hordeum, and 3) chemodiversity of flavonoid and diterpenoid phytoalexins in rice. These studies demonstrated dynamic changes in secondary metabolism during evolution, indicating the adaptation of plants to their environment by repeating scrap-and-build cycles.

著者

Atsushi Ishihara Kana Ando Anna Yoshioka Koichi Murata Yu Kokubo Noriko Morimoto Naoki Ube Yukinori Yabuta Makoto Ueno Shin-ichi Tebayashi Kotomi Ueno Kumiko Osaki-Oka

出版者

Pesticide Science Society of Japan

雑誌

Journal of Pesticide Science (ISSN:1348589X)

巻号頁・発行日

pp.D18-063, (Released:2019-03-12)

参考文献数

36

被引用文献数

10

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We investigated the effect of treatment with hot water extracts from the spent mushroom substrates (SMSs) of Lentinula edodes and Hypsizygus marmoreus on the resistance of rice leaves to Pyricularia oryzae infection. The spraying of the SMS extracts clearly suppressed the development of lesions caused by Py. oryzae infection. The accumulation of phytoalexins momilactones A and B, oryzalexin A, and sakuranetin was markedly induced by the spraying of extracts. The enhanced expression of defense related genes PR1b and PBZ was also found in leaves sprayed with the extracts. Treatments with the extracts also affected phytohormone levels. The levels of N6-(Δ2-isopentenyl)adenine and trans-zeatin markedly increased in response to treatment, whereas the levels of salicylic and jasmonic acids were largely unchanged.

著者

Tomoyasu Taguchi Atsushi Ishihara Hiromitsu Nakajima

出版者

日本マイコトキシン学会

雑誌

マイコトキシン (ISSN:02851466)

巻号頁・発行日

vol.65, no.2, pp.131-142, 2015-07-31 (Released:2015-09-01)

参考文献数

37

被引用文献数

1

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Fungal contamination of food is one of the most important food safety concerns, however effective techniques to prevent fungal contamination and/or control fungal growth in foods have not yet been established. Some endogenous volatile compounds in plants have antibacterial and/or antifungal activities. For example, when some plants are damaged, they release aliphatic aldehydes with six or nine carbons to protect themselves from microbial infection. Patulin is the major mycotoxin that contaminates apples and apple juice worldwide, and it is regulated in many countries. Patulin has been shown to be immunotoxic and neurotoxic by animal experiments. Many species of Penicillium and Aspergillus produce patulin, but P. expansum is the most typical species responsible for patulin contamination in apples. We attempted to assess the effects of aliphatic aldehydes on P. expansum. Aliphatic aldehydes composed of 3–6 carbons bearing an E double bond at the α-position completely inhibited the fungal growth and suppressed colony formation from spores at relatively low concentrations. On the basis of the structure-activity relationship, the antifungal activity of the compounds is probably attributable to the interaction of the aldehyde group with biological macromolecules. On the other hand, aliphatic aldehydes with 8–10 carbons stimulated patulin production by P. expansum. The results of a reverse transcription-quantitative polymerase chain reaction analysis suggested that the stimulation was partially due to enhanced transcription of some patulin biosynthetic genes. The effects of volatiles of apple on patulin production by P. expansum were also studied. Some volatile compounds, that is, 2-mehtylbutanoic acid and ethyl 2-methylbutanoate, were found to stimulate patulin production. These findings will contribute to the development of new techniques to prevent and control fungal and mycotoxin contamination of foods.