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キノコに代表される担子菌類は，食用や漢方など，古くから食品や医薬品として利用されてきた。しかしながら，その他の利用，特に，有用物質生産を目的とした「生体触媒」としての有用性については，ほとんど知られていなかった。そこで，本研究では，食用キノコを中心とした担子菌類の，生体触媒としての可能性を探るため，担子菌由来の細胞外分泌型リパーゼの探索を目的として研究を行った。, Basidiomycetes containing edible mushrooms have been used for foods and traditional Chinese medicines since ancient times. However, the possibility of its application in other fields of the mushrooms is not well known. Therefore, in this study, in order to explore the possibility of edible mushrooms as biocatalysts, we investigated the screening for extracellular lipases derived from basidiomycetes containing edible mushroom.

南硫黄島から2017年に採集されたきのこ類についてリスト化するともに子実体写真で紹介する。合計12標本(2門2綱4目9科11属11種)が採集され、全て腐生菌もしくは木材腐朽菌であった。多くは南硫黄島に自然分布する種であると思われる。, Several species of mushrooms (Ascomycota and Basidiomycota) collected and identified from Minami-Iwo-To Island, Japan in 2017 are reported with photographs and a list of specimens. A total of 12 specimens (2 phyla, 2 classes, 4 orders, 9 families, 11 genera, and 11 species) were collected. All species were either saprophytes or wood decay fungi and most are considered native to the island.

P(論文), Trehalase activity in a homogenized preparation from the fruit body of king oyster mushroom (eryngii), Pleurotus eryngii was studied in detail. Distribution of trehalose and trehalase activity was higher in the cap (pileus) fraction than in the other positions such as stalk (stipe). The tretalase peak 1 was purified by the Sephacryl S-200 and Toyopearl HW-55 column chromatography. Electorophoretic analysis of trehalase gave values of molecular weight of 36~37kDa, and oligomeric forms and blycoprotein forms of trehalase were suggested by the band patterns of resulting gels. Optimum conditons of pH and temperature were determined to be pH5.0 and 30℃, respectively. Trehalase peak 1 showed higher reactivity to α-, α-trehalose, whereas peak 2 enzyme showed higher activity to β-,β-trehalose, methyl-β-glucoside, and cellobiose, indicating that this enzyme might have a substrate specificity such asβ-glucosidase.

P(論文), Carbohydrate components and their related carbohydrate activities in a homogenized preparation of the fruit body of king oyster mushroom (eryngii), Pleurotus eryngii, were studied in detail. The low-molecular weight fractions contained a significant amount of trehalose compared with other constituents of mono-saccharides, and its concentration was 18.7% of the dry weight. Polysaccharides in the high-molecular weight fraction were separated into four fractions, A~D, which were analyzed for the yields and sugar components. The polysaccharide fractions were also analyzed by the ion-exchange and gel-filtration column chromatography, and enzymatic hydrolysis. The results suggested that typical polysaccharide components in the fruit body of eryngii might be β-glucan and galactan, corresponding to the known results obtained by the liquid-cultured eryngii. A crude enzyme solution was prepared from the fruit body of eryngii, and various carbohydrase activities were measured using 27 substrates at pH 5.2, 6.5 and 7.8. A higher enzyme activity was detected for the substrates of laminarin and trehalose. Occurrence of trehalase activity correlated with the high concentration of trehalose in the fruit body of eringii.

Coriolus versicolor stain producuces extracellarly lignin-decomposing enzymes such as laccase, lignin peroxidase, and Mn peroxidase. To achieve the high yield of these enzymes, we studied on the condition of culture method and/or the effect of several inducers on lignin-decomposing activities to effectively produce these enzymes. As a result, the production of lignin-decomposing enzymes by C.versicolor was higher using surface culture method than that using shaking culture method. Moreover, by adding hespersin to culture medium, the production of these enzymes was remarkably increased. Especially, in the case with 0.5mM hespersin, laccase produced by C.versicolor IFO 4937 achieved at ca.lOOnkat/ml, which was about 2.5-fold higere than that without one., C.versicolorは細胞外にラッカーゼ，リグニンパオキシダーゼ，マンガンペルオキシダーゼなどのリグニン分解酵素を生産する。そこで，それらの酵素の生産量を増大するために，培養条件とフェノール系化合物の添加効果について検討した。その結果，リグニン分解酵素を効率よく生産するには振とう培養よりも静置培養が有効であることがわかった。また，へスペリジンの添加はリグニン分解酵素の分泌生産量を増大することがわかった。特に，C.versicolor IFO 4937によって生産されるラッカーゼはへスペリジンをO.5mM添加することで最大酵素活性が約1OOnkat/mlに達し，無添加の場合の約2.5倍まで向上することができた。

Some biotic and abiotic factors causal to the deterioration of roadside trees were surveyed in Fukuoka City on 23 species planted along 22 main streets. Various fruit bodies of basidiomycete, imperfect fungi and bacterial canker disease as well as insect pests were detected. Forty-six fungi strains were obtained in this survey. Aphyllophorales basidiomycete was the most abundant fungi found in surveyed raodside trees. Fruit bodies of 7 edible mushroom species were identified on the scaffold limbs, trunks and root collars of roadside trees. Population of all woodinhabiting basidiomycetes from healthy and diseased trees were significantly different. Robinia pseudoacacia declined severely with mycerial development and fruit body formation of white rot fungi, Fomitella fraxinea on root collars. It is conceivable that low soil pH might be a major factor. Fifty-one species of tree insects were identified in this survey, major pests being two species of termites (Isoptera), Reticulitermes speratus kyushuensis and Coptotermes formosanus which significantly attacked ten tree species. Cerambycid beetles, Anoplophora malasiaca and Eupromus ruber severely damaged Platanus orientalis and Machilus thunbergii, respectively. Root damage status corresponded significantly to the degree of upper tree decline. Results clearly show differences between evergreen broad-leaved trees and deciduous broad-leaved trees in tolerance to wood-inhabiting basidiomycetes and tree-parasitic insects. Overall, this preliminary survey documents some biotic and abiotic factors may contribute to roadside tree decline in Fukuoka City., 福岡市内の主要22路線に植栽されている23種の街路樹について,木材腐朽性担子菌および昆虫による衰微を調査した.全調査木1,067本のうちの約3分の1の街路樹で被率が認められた.担子菌のヒダナシタケ目サルノコシカケ科に属するものの子実体が頻繁に観察された.同定された担子菌46種のうち7種の食用担子菌の子実体が認められた.枝条部や樹幹部に子実体が認められたものは樹勢の衰えが顕著で,形成層や辺材部で二次菌糸が単離された.調査した23樹種のうちでは,特に,ニセアカシア,エンジュの衰弱が著しく,その根ざわ部分に白色腐朽菌のベッコウタケ子実体の着生がみられ,被害の激しいものは心材部まで二次菌糸の蔓延が認められた.昆虫では,寄生，共生および補食性昆虫を除き合計51種が確認された.特にシロアリ,カミキリムシ等の食材性昆虫の被害が顕著であった.そのうちシナサワグルミ,シダレヤナギおよびこセアカシアでは枯死に到る被害が見いだされた.またプラタナスではゴマダラカミキリの,タブノキではホシベニカミキリの激しい加害が認められ,幼虫のトンネルにアリ,シロアリおよび菌類の二次的侵入が認められた.また,土壌酸性度の低下が著しく,伐根調査の結果,細根部が強く侵害を受け主根部まで二次菌糸が蔓延していることが分かった.根系部の衰弱は樹木の地上部の侵害度と高い相関性を示した.今回の調査の結果,樹種や土壌要因等が街路樹の衰微に大きな影響をおよぼしているものと考えられた．

It has been reported that C. versicolor produces extracellarly lignin-decomposing enzymes such as laccase and lignin peroxidase. In order to achieve the high yield of two enzymes, we cultured the fungi by the surface culture method, investigated the production of enzymes.Moreover, purification and characterization of these enzymes were also investigated. As a result, the activities of laccase and lignin peroxidase achieved about 1.60, and 0.45nkat/ml, respectively. Further, it was found that two enzymes could be purified easily by DEAE-Toyopearl and the molecular weights of laccase and lignin peroxidase were estimated to be 38,000, 42,000, using electrophpresis, respectively., 白色腐朽菌C.versicolor IFO 4937は，木材中のリグニンを分解するラッカーゼやリグニンパーオキシダーゼを生産すると報告されている。本研究では，より効率的な酵素生産を目的として，表面培養法を用いたリグニン分解酵素の生産について検討した。さらに，この2種の酵素を分離精製し，それぞれの性質も検討した。その結果，本菌株は最大酵素活性でラッカーゼ，およびリグニンパーオキシダーゼを1.60，および0.45nkat/ml生産することができた。また，両酵素はDEAE-Toyopearlを用いたイオン交換クロマトグラフィーにより容易に分離精製できた。精製したラッカーゼ，リグニンパーオキシダーゼの分子量はポリアクリルアミドゲル電気泳動によりそれぞれ38,000，42,000であることがわかった。

研究科: 千葉大学大学院薬学研究院, 修了年:1988, 学位:千大院薬博乙第58号

研究科: 千葉大学大学院薬学研究院, 修了年:1988, 学位:千大院薬博乙第58号