Oxford University Press (OUP)Acta Medica Okayama1347-69478892024Solid-state cultivation of multiple industrial strains of koji mold on different Thai unpolished rice cultivars: biotransformation of phenolic compounds and their effects on antioxidant activity11171125ENJirayuJitpakdeeGraduate School of Environmental and Life Science, Okayama UniversityHideyukiYamashitaHiguchi Matsunosuke Shoten Co., Ltd. TakuroNakagawaHiguchi Matsunosuke Shoten Co., Ltd. TeruhikoNitodaGraduate School of Environmental and Life Science, Okayama UniversityHiroshiKanzakiGraduate School of Environmental and Life Science, Okayama UniversityColored rice is abundant in polyphenols, and koji molds have potential for biotransformation. This study aimed to produce Thai-colored rice koji to study its polyphenolic biotransformation. Four industrial koji mold strains: Aspergillus oryzae 6001, A. oryzae 6020, A. sojae 7009, and A. luchuensis 8035, were cultivated on unpolished Thai-colored rice (Riceberry and Sangyod), unpolished Thai white rice (RD43), and polished Japanese white rice (Koshihikari). We discovered that koji molds grew on all the rice varieties. Methanol extracts of all rice kojis exhibited an approximately 2-fold or greater increase in total phenolic content and DPPH antioxidant activity compared to those of steamed rice. Moreover, quercetin, quercetin-3-O-glucoside, isorhamnetin-3-O-glucoside, ferulic acid, caffeic acid, protocatechuic acid, vanillic acid, (+)-catechin, and (–)-epicatechin content increased in Riceberry and Sangyod koji samples. Consequently, Aspergillus solid-state cultivation on unpolished Thai-colored rice exhibited higher functionalization than the cultivation of unpolished Thai white rice and polished Japanese white rice.No potential conflict of interest relevant to this article was reported.Oxford University Press (OUP)Acta Medica Okayama1347-69478982025Microbial biotransformation of proteins into amino acids in unpolished Thai and polished Japanese rice varieties cultivated with distinct industrial strains of koji mold12171226ENJirayuJitpakdeeGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityKazunariItoIndustrial Technology Center of Okayama PrefectureYukaTaninoIndustrial Technology Center of Okayama PrefectureHayatoTakeuchiIndustrial Technology Center of Okayama PrefectureHideyukiYamashitaHiguchi Matsunosuke Shoten Co., Ltd.TakuroNakagawaHiguchi Matsunosuke Shoten Co., Ltd.TeruhikoNitodaGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityHiroshiKanzakiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityWe previously reported the cultivation of industrial koji mold strains to produce unpolished Thai-colored rice kojis. These kojis, along with those made from unpolished Thai white rice and polished Japanese white rice, showed increased polyphenol content after cultivation, with the highest levels observed in unpolished Thai-colored rice kojis. In this study, an increase in both proteinogenic and non-proteinogenic amino acid contents, particularly γ-aminobutyric acid (GABA) content, was observed in both unpolished Thai and polished Japanese rice kojis, suggesting the ability of koji mold in the biotransformation of proteins. This increase was almost comparable even when using different rice varieties; in contrast, it varied depending on the koji mold strain used. The observed increase in both polyphenol and functional amino acid contents, especially GABA content, highlights the potential of unpolished Thai and polished Japanese rice kojis, particularly unpolished Thai-colored rice koji, as multifunctional materials, benefiting from polyphenol and amino acid functionalities.No potential conflict of interest relevant to this article was reported.Japan Society for Bioscience, Biotechnology, and AgrochemistryActa Medica Okayama0916-84517142007Three antinematodal diterpenes from Euphorbia kansui10861089ENJian-XiaoShiZhi-XuanLiTeruhikoNitodaMinoruIzumiHiroshiKanzakiNaomichiBabaKazuyoshiKawazuShuheiNakajimaThree compounds, 20-O-acetyl-[3-O-(2'E,4'Z)-deca-dienoyl]-ingenol (1), 20-O-acetyl-[5-O-(2'E,4'Z)-decadienoyl]-ingenol (2) and 3-O-(2'E,4'Z)-decadienoylingenol (3), were isolated from Euphorbia kansui under the bioassay-guided method. Each compound showed the same antinematodal activity against the nematode, Bursaphelenchus xylophilus, at a minimum effective dose (MED) of 5 mu g/cotton ball.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548611997電気生理学的手法を用いた昆虫神経作用物質の探索109113ENTeruhikoNitodaA simple and rapid bioassay was developed to search for novel insect neuroactive substances.This method was based on the electrophysiological response of the metathoracic legnerve of Periplaneta americana.Using this assay,41 methanol extracts of Kenyan plant and 15 methanol extracts of Indonesia plants were tested to show various activities.Several compounds were isolated from these methanol extracts with the guidance of the activity increasing spontaneous-impulse frequencies.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548711998Calophyllum inophyllumの抗ＨＩＶ活性成分 inophyllum A, B, C, D, E, P の液体クロマトグラフィーによる分析法の確立1316ENKazuyoshiKawazuTeruhikoNitodaHiroshiKanzakiIn order to optimize cell culture conditions for producing inhibitors of HIV reverse transcriptase isolated from Calophyllum , inophyllum , a rapid and accurate anaalytical method for determining the quantity of the inhibitors, inophyllums A , B , C , D , E , and P was desired . We have established a quantitative analytical method using HPLC ,together with LCMS .No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548711998Production of Antibacterial Triterpene Acids Not Detected in the Native Plant by Cell Suspension Culture of Tectona grandis912ENKazuyoshiKawazuErlyMarwaniAkikoKobayasiTeruhikoNitodaHiroshiKanzakiThe callus culture of Tectona grandis was previouly reported by us to produce five antibacterial acids which occurred only in very small amounts or were not detected in the native plant. This paper shows the production of these antibacterial compounds in much higher by cell suspension culture of the plant.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548811999新規の環状ジペプチド脱水素酵素とその活性測定法の確立711ENHiroshiKanzakiKazumiAkazawaDaisukeImuraTeruhikoNitodaThe cell-free extract prepared from cells of an albonoursin-producing actinomycete Streptomyces sp. KO2388 was found to catalyze the dehydrogenation of cyclo (L-Phe-L-Leu) (CFL) to albonoursin. This is the first report for the dehydrogenation at the α,β-positions of amino acid residues. The simple method for determining the dehydrogenation activity was devised by measuring the increase in UV absorption of the reaction mixture at 317nm, λmax(ε25,400) of albonoursin, where CFL had no absorption. Phenazine methosulfate was the most active cofactor for the dehydrogenation among several hydrogen acceptors.No potential conflict of interest relevant to this article was reported.Acta Medica Okayama2003糸状菌が生産するキチナーゼ阻害物質に関する研究ENTeruhikoNitodaNo potential conflict of interest relevant to this article was reported.