Obihiro University of Agriculture and Veterinary Medicine
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シーベリー果汁に搾汁残渣抽出液を添加すると 酸化剤による酸化を抑制する
Get PDFapplication/pdfシーベリー果汁のDPPHラジカル消去活性は、酸化剤を添加して30分後には酸化剤添加前の26.9±0.9％まで顕著に低下した。しかし、搾汁残渣である果皮＆果肉抽出液に同様の条件で酸化剤を添加したときには酸化剤添加前の73.4±1.8％、種子抽出液に添加した場合には酸化剤添加前の88.8±2.0％、パルプ部抽出液に添加した場合には酸化剤添加前の58.5±2.3％で、それらの酸化の進行は、果汁のそれよりも遅いことが示された。
果汁の酸化剤による酸化を抑制する目的で、果汁に各残渣抽出液を添加して、DPPHラジカル消去活性の残存率に及ぼす影響を検討した。シーベリー果汁に種子抽出液を混合して両者の合計ポリフェノール濃度を2倍にしたところ、酸化剤添加30分後のDPPHラジカル消去活性残存率は84.4±3.3％、果皮＆果肉抽出液を混合して両者の合計ポリフェノール濃度を2倍にしたときの残存率は76.6±1.5％、パルプ部抽出液を混合して両者の合計ポリフェノール濃度を2倍にしたときの残存率は72.2±1.1％、いずれにおいても果汁単独のときに比べて酸化が顕著に抑制された。さらに、果汁に添加する種子抽出液のポリフェノール濃度を２倍、３倍に増大して同様の酸化実験をおこなったところ、添加量に依存してDPPHラジカル消去活性の保持率が有意に増大した。一方、種子以外の残渣抽出液のポリフェノール濃度を２倍、３倍に増大しても、DPPHラジカル消去活性の保持率に有意な増大は認められなかった。これらの結果は、シーベリー果汁に3種類のいずれの残渣抽出液を添加しても酸化の抑制効果はみとめられるが、特に種子抽出液の添加は、果汁の酸化抑制に高い効果のあることを示している。The DPPH radical scavenging activity of seaberry juice was significantly decreased to 26.9±0.9% of that before the addition of oxidant after 30 min of addition of oxidant. However, when the oxidant was added to the juice residue, peel and pulp extract, under the same conditions, their oxidation was 73.4±1.8% of that before the addition of the oxidant, 88.8±2.0% of that before the addition of the oxidant when it was added to the seed extract, and 58.5±2.3% of that before the addition of the oxidant when it was added to the pulp part extract. The progression of oxidation was shown to be slower than that of fruit juice.
In order to inhibit the oxidation of fruit juice by oxidants, the effect of adding each residue extract to the juice on the residual DPPH radical scavenging activity was investigated. When the seed extract was mixed with the seaberry juice and the total polyphenol concentration of both was doubled, the residual rate of DPPH radical scavenging activity after 30 minutes of addition of the oxidant was 84.4±3.3%. When the peel and pulp extract was mixed and the total polyphenol concentration of both was doubled, the residual rate was 76.6±1.5%. When the pulp extract was mixed with the pulp extract and the total polyphenol concentration of both was doubled, the residual rate was 72.2±1.1%. In all cases, oxidation was significantly suppressed compared to fruit juice alone. Furthermore, when the concentration of polyphenols in the seed extract added to the juice was increased two-fold or three-fold, the retention of DPPH radical scavenging activity was significantly increased depending on the amount added. On the other hand, there was no significant increase in the retention of DPPH radical scavenging activity when the concentration of polyphenols in the extract of residues other than seeds was increased two-fold or three-fold. These results indicate that the addition of any of the three residue extracts to the seaberry juice has an inhibitory effect on oxidation, but the addition of the seed extract in particular is highly effective in inhibiting the oxidation of the juice.departmental bulletin pape
DNAメタバーコーディングによる小型齧歯類の食性解析 ―エゾモモンガの採食資源とその季節変化
Get PDFapplication/pdf季節変化が明瞭な温帯域，亜寒帯域に生息する多くの植食性哺乳類において、食性の季節変化が確認されている。タイリクモモンガPteromys volansの亜種であるエゾモモンガP. volans oriiは、北海道の森林に生息する植食性のリス科齧歯類である。本亜種の食性については、野外における直接観察、痕跡の確認、飼育下における給餌実験等に基づいた報告があるが、これらの方法では、本亜種が野外で採食する全ての資源を把握することは困難である。そこで本研究では、帯広市内の河畔林において採集された本亜種の糞サンプルを用いて、DNAメタバーコーディング法により、食性の季節変化を包括的に推定することを試みた。 さらに、これまでに帯広市内において直接観察によって報告されている本亜種の食性データとの比較を行い、DNAメタバーコーディング法の有用性を検討した。糞中に含まれる植物種を解析した結果、推定された植物は季節間で有意に異なり、本亜種の採食パターンの季節変化が示された。また、ニレ科とシラカンバについては、季節を問わず利用されており、主要な採食資源であることが明らかになった。加えて、各季節で草本植物が検出され、樹上性である本亜種が地上で採食をする可能性が示唆された。直接観察法のデータと比較した結果、DNAメタバーコーディング法ではより広範囲の採食資源を推定できることが明らかになった。しかしながら、採食された植物種の特定が難しい場合があるという欠点も示された。DNAメタバーコーディング法によって包括的に食性を推定し、直接観察によってこれを裏付けるという調査方法を確立することによって、本亜種に限らず、今後の野生動物の食性研究の効率化に繋がるであろう。In the temperate and subarctic zones, herbivorous mammals change their feeding habits seasonally. Pteromys volans orii, a Siberian flying squirrel subspecies endemic to Hokkaido, Japan, also uses food resources seasonally. To date, the feeding habits of P. volans orii has been examined by direct observations, analysis of feeding remains, and feeding experiments in captivity. However, it is difficult to understand its complete feeding habit based on these methods. Therefore, we examined its feces using the DNA meta-barcoding technique. In 2020, we conducted the study in a riparian forest in Obihiro during periods of no snow (in spring, summer, and autumn). In addition, to evaluate the DNA meta-barcoding technique, we compared our results with those reported previously by direct observations. We found that the feeding habits of this subspecies were significantly different between seasons. The family Ulmaceae and Betula platyphylla were usually detected in the feces, suggesting that these could be the main food resources for P. volans orii. The number of species and genera detected by DNA meta-barcoding was much higher than that reported previously by direct observations; however, it was sometimes difficult to precisely identify the species or genus, because of a limited DNA database. Therefore, to understand the precise feeding habits of P. volans orii, it is essential to first obtain its outline by DNA meta-barcoding, and based on this information, the exact food items can be ascertained by direct observation. The combination of both methods could aid successful investigation of the feeding habits of other mammalian species.departmental bulletin pape
国立公園の持続可能な利用を妨げる認識のズレ : 釧路湿原国立公園を事例に
Get PDFapplication/pdf本研究の目的は、年々深刻化する環境問題の解決策の一つとして「国立公園」の持続可能な利用方法を提起する事である。「国立公園」とは、自然景観の保護と利用の増進を図り、国民の保健、休養、教化に資する事を目的とする自然公園である。本研究では、「国立公園」の利用方法の一つとして注目される「観光」に焦点を当て、現在の日本政府の観光政策が環境保護政策と両立出来ているのかを検討した。
まず、第1 節では、日本の「国立公園」の歴史について日本と海外とを比較した後、日本の「国立公園」が環境保全に対して弱い制度である事を明らかにした。次に、第2 節では、世界と日本の観光の歴史、観光形態を説明した後、「国立公園」で観光業が展開される上での利点と欠点について論じた。特に「国立公園」で実施される観光が自然環境配慮型に向かう必要性を強調した。続く第3 節と第4 節では、日本に34 個ある「国立公園」の中でも、湿原を中心に構成された特異的な自然環境及び設立の経緯を有する釧路湿原国立公園を事例として取り上げ、観光業に関わっている利害関係者のインタビューを実施した。その結果、「国立公園」で展開される観光政策に対して利害関係者間で認識のズレが存在する事が明らかになった。「国立公園」を自然保護区として管理したい意見と経済活動の場として観光地開発したい意見との間で、実際に現場で自然環境の保護と利用の両立を目指すアクターが持つ政策への不満が明らかになった。
以上の事から、観光業を展開する上で日本の「国立公園」は、環境への配慮に関する政策が不十分であるために持続可能な利用が妨げられており、環境及び観光政策を見直す必要性がある事が示唆された。もって、「国立公園」の持続可能な利用に資する上での環境政策に反映する事を期待したい。The aim of this research is to analyze the compatibility between the “tourism policy” and “environmental protection policy” implemented by Japanese government. To achieve this goal, this paper focused on Japanese National Park System and it is divided in four sections. In the first two, this study reviews the history of Japanese national parks and remarks the negative effects that massive tourism has on environmental protection. Later, in sections three and four, this paper explains the main aspects of the case study (Kushiro Shitsugen National Park) and shows the results of the interviews carries out with the actors involved in the tourism policy in this park. The main result is that there is a discrepancy among stakeholders around a profitable tourist activity and the establishment of true environmental protection. In conclusion, this study shows that there are not the conditions to implement a massive tourism activity in Japanese National Park System. It is necessary to rethink a policy that allows a sustainable use of national parks and seek a tourism policy that contributes to environmental protection.departmental bulletin pape
北海道のホルスタイン集団における 泌乳曲線の推定ならびに体細胞スコアの遺伝的能力評価に関する研究
Get PDF帯広畜産大学博士（農学）2021application/pdf博士学位論文大学院畜産学研究科
畜産科学専攻博士後期課程doctoral thesi
Azole-resistant Aspergillus fumigatus as an emerging worldwide pathogen
Get PDFapplication/pdfAspergillus fumigatus, a ubiquitous pathogen, causes aspergillosis in humans, especially in immunodeficient patients. Azoles are frontline antifungal drugs for treating aspergillosis. The recent global emergence of azole resistance in A. fumigatus has become a serious problem worldwide. It has arisen through two routes: long-term azole medical therapy, called the patient route, and the use of azole fungicides in its habitats especially for agricultural activities, called the environmental route. Resistant strains developed through the latter route show cross-resistance to medical azoles because of the identical molecular target Cyp51A between azole compounds used for medical treatment and agricultural disease control. In azole-resistant strains arising through the environmental route, A. fumigatus is observed frequently to possess mutations in the cyp51A gene linked to tandem repeats in the promoter region such as TR34/L98H and TR46/Y121F/T289A. The results of microsatellite genotyping analyses of resistant A. fumigatus strains have suggested a transboundary spread of this microorganism in many countries. Diverse actors are involved in the global highway of transmission. Therefore, the matter must be addressed as a “One Health” issue. This review presents a background of azole resistance in A. fumigatus and introduces newly discovered difficulties generated as this pathogen spreads worldwide. © 2021 The Societies and John Wiley & Sons Australia, Ltdjournal articl
Dynamics of sperm-oviduct interaction that regulates maternal immune response in cattle
Get PDF帯広畜産大学博士（畜産衛生学）2020application/pdf博士学位論文
大学院畜産学研究科 畜産衛生学専攻
Doctoral Program in Animal and Food Hygienedoctoral thesi
Shade Avoidance and Light Foraging of a Clonal Woody Species, Pachysandra terminalis
Get PDFapplication/pdf(1) Background: A central subject in clonal plant ecology is to elucidate the mechanism by which clones forage resources in heterogeneous environments. Compared with studies conducted in laboratories or experimental gardens, studies on light foraging of forest woody clonal plants in their natural habitats are limited. (2) Methods: We investigated wild populations of an evergreen clonal understory shrub, Japanese pachysandra (Pachysandra terminalis Siebold & Zucc.), in two cool-temperate forests in Japan. (3) Results: Similar to the results of erbaceous clonal species, this species formed a dense stand in a relatively well-lit place, and a sparse stand in a shaded place. Higher specific rhizome length (i.e., length per unit mass) in shade resulted in lower ramet population density in shade. The individual leaf area, whole-ramet leaf area, or ramet height did not increase with increased light availability. The number of flower buds per flowering ramet increased as the
canopy openness or population density increased. (4) Conclusions: Our results provide the first empirical evidence of shade avoidance and light foraging with morphological plasticity for a clonal woody species.journal articl
Alteration of fecal microbiota by fucoxanthin results in prevention of colorectal cancer in AOM/DSS mice
Get PDFapplication/pdfFucoxanthin (Fx), a marine carotenoid found in edible brown algae, is well known for having anticancer properties. The gut microbiota has been demonstrated as a hallmark for colorectal cancer progression in both humans and rodents. However, it remains unclear whether the gut microbiota is associated with the anticancer effect of Fx. We investigated the chemopreventive potency of Fx and its effect on gut microbiota in a mouse model of inflammation-associated colorectal cancer (by azoxymethane/dextran sulfate sodium treatment). Fx administration (30 mg/kg bw) during a 14 week period significantly inhibited the multiplicity of colorectal adenocarcinoma in mice. The number of apoptosis-like cleaved caspase-3high cells increased significantly in both colonic adenocarcinoma and mucosal crypts. Fx administration significantly suppressed Bacteroidlales (f_uc; g_uc) (0.3-fold) and Rikenellaceae (g_uc) (0.6-fold) and increased Lachnospiraceae (g_uc) (2.2-fold), compared with those of control mice. Oral administration of a fecal suspension obtained from Fx-treated mice, aimed to enhance Lachnospiraceae, suppress the number of colorectal adenocarcinomas in azoxymethane/dextran sulfate sodium-treated mice with a successful increase in Lachnospiraceae in the gut. Our findings suggested that an alteration in gut microbiota by dietary Fx might be an essential factor in the cancer chemopreventive effect of Fx in azoxymethane/dextran sulfate sodium-treated mice.journal articl
ヒグマと共に生きるために
Get PDFapprlication/pdf北海道の人とヒグマの関わり人とヒグマヒの共存のためにInteraction between brown bears and the people of HokkaidoEncouraging the coexistence of people and brown bears「農業共生圏高度専門家育成事業」の一環として作成されたもの
https://www.obihiro.ac.jp/biodiversityothe