{"created":"2023-05-15T15:29:37.343434+00:00","id":19391,"links":{},"metadata":{"_buckets":{"deposit":"c089451a-4639-460c-b910-049d8221873b"},"_deposit":{"created_by":15,"id":"19391","owners":[15],"pid":{"revision_id":0,"type":"depid","value":"19391"},"status":"published"},"_oai":{"id":"oai:sucra.repo.nii.ac.jp:00019391","sets":["94:429:431:432:992"]},"author_link":[],"item_113_alternative_title_1":{"attribute_name":"タイトル（別言語）","attribute_value_mlt":[{"subitem_alternative_title":"シアノバクテリアの生長とストレスに係る光応答に関する研究"}]},"item_113_biblio_info_9":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2020","bibliographicIssueDateType":"Issued"}}]},"item_113_date_35":{"attribute_name":"作成日","attribute_value_mlt":[{"subitem_date_issued_datetime":"2021-09-16","subitem_date_issued_type":"Created"}]},"item_113_date_granted_20":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2020-09-23"}]},"item_113_degree_grantor_22":{"attribute_name":"学位授与機関","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_name":"埼玉大学"}],"subitem_degreegrantor_identifier":[{"subitem_degreegrantor_identifier_name":"12401","subitem_degreegrantor_identifier_scheme":"kakenhi"}]}]},"item_113_degree_name_21":{"attribute_name":"学位名","attribute_value_mlt":[{"subitem_degreename":"博士(工学)"}]},"item_113_description_13":{"attribute_name":"形態","attribute_value_mlt":[{"subitem_description":"x, 120p","subitem_description_type":"Other"}]},"item_113_description_23":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"The continuous supply of nutrients like phosphorus to water bodies and global warming have promoted the presence of cyanobacteria globally. Due to the continuous spreading of harmful Cyanobacteria, the water environment is facing many challenges such as bad odor, releasing of cyanotoxins; and under the bloom, conditions losing clogging of water systems and reduction of aesthetic values. The biological and physical control of Cyanobacteria is getting increased attention as it is relatively environmentally sound and low cost in application. To understand the favorable and unfavorable light conditions and exposure durations of cyanobacteria, morphological and physiological responses of cyanobacteria to different light conditions and light exposure durations, and interaction of cyanobacteria with macrophyte species under different light conditions, a series of experiments were conducted. Experiments were conducted under controlled environmental conditions in incubators.\n\nThere is an information gap exists regarding light‐induced oxidative stress and the species‐specific behavior of cyanobacteria under various light levels. A study was conducted to evaluate the comparative effects of different light intensities on the growth and stress responses of two cyanobacteria species, Pseudanabaena galeata （strain NIES 512） and Microcystis aeruginosa （strain NIES 111）, after periods of two and eight days. The cyanobacterial cultures were grown under the following different light intensities: 0, 10, 30, 50, 100, 300, and 600 μmol·m-²·s-¹. The optical density （OD730）, chlorophyll a （Chl‐a） content, protein content, H₂O₂ content, and the antioxidative enzyme activities of catalase （CAT） and peroxidase （POD） were measured separately in each cyanobacteria species. P. galeata was negatively affected by light intensities lower than 30 μmol·m-²·s-¹ and higher than 50 μmol·m-²·s-¹. A range of 30 to 50 μmol·m-²·s-¹ light was favorable for the growth of P. galeata, whereas M. aeruginosa had a higher tolerance for extreme light conditions. The favorable range for M. aeruginosa was 10 to 100 μmol·m-²·s-¹\n\nThe diurnal variation oxidative stress and the antioxidant activities of cyanobacteria were tested to understand the oxidative stress and antioxidant activities under varying light conditions and their favorable and stressed phases during a single day. Two harmful cyanobacteria species, Phormidium ambiguum and M. aeruginosa were investigated under controlled environmental conditions. The photosynthetically active radiation （PAR） started at 0 μmol·m-²·s-¹ 06:00 h）, increased by ~25 or ~50 μmol·m-²·s-¹every 30 min, peaking at 300 or 600 μmol·m-²·s-¹ （12:00 h）, and then decreased to 0 μmol·m-²·s-¹ by 18:00 h. The H₂O₂ and antioxidant activities were paralleled to light intensity. Higher H₂O₂ and antioxidant levels （guaiacol peroxidase, catalase （CAT）, and superoxidase dismutase） were observed at 600 μmol·m-²·s-¹ than at 300 μmol·m-²·s-¹. Changes in antioxidant levels under each light condition differed between the species. Significant correlations were observed between antioxidant activities and H₂O₂ contents for both species, except for the CAT activity of P. ambiguum at 300 μmol·m-²·s-¹. Under each of the conditions, both species responded proportionately to oxidative stress; even under maximum light intensities （300 or 600 μmol·m-²·s-¹ PAR intensity）, neither species was stressed. Studies using extended exposure durations are warranted to better understand the growth performance and long-term physiological responses of both species.\n\nThe influence of cyanobacteria on macrophytes was investigated by exposing E. densa plants to a low concentration of （OD₇₃₀ = 0.04） M. aeruginosa for seven days, under different photosynthetically active radiation （PAR） intensities （0, 50, 100, 200, and 300 μmol·m-²·s-¹）. Experiments were conducted under controlled conditions inside incubators. The H₂O₂ content, antioxidant responses, pigmentation, and chlorophyll fluorescence parameters were measured. The biochemical parameters of E. densa varied with PAR intensity; under the 50 and 100 μmol·m-²·s-¹ PAR intensities, E. densa performed relatively better than under other intensities. When exposed to M. aeruginosa, the levels of the measured biochemical parameters reduced in E. densa.\n\nUnder unfavorable light conditions, the optical density of M. aeruginosa was also reduced when E. densa was also present. Even at low concentrations, the presence of M. aeruginosa in the water can have a negative effect on E. densa pigmentation and physiological parameters, though E. densa also has negative effects on M. aeruginosa growth. There were reduced OD₇₃₀ and increased H₂O₂ formation in the M. aeruginosa was observed due to the co-existence with the E. densa.\n\nThe combination of light stress, together with existing measures （bubbling or mixing） can be used to suppress the growth of cyanobacteria further. Further research is recommended including investigating, recovery of cyanobacteria after high light exposure, macrophyte allopathy on cyanobacteria and influence of cyanobacterial circadian rhythm on light exposure. The physiological and growth responses of cyanobacteria under these conditions should be studied. Information such as diurnal stress phases of cyanobacteria, allopathic macrophyte species and circadian responses of cyanobacterial physiology are essential to formulate effective cyanobacteria control approaches.","subitem_description_type":"Abstract"}]},"item_113_description_24":{"attribute_name":"目次","attribute_value_mlt":[{"subitem_description":"CHAPTER 1 INTRODUCTION AND LITERATURE REVIEW................................................................ 1\n1.1 Freshwater ecosystems ......................................................................................... 2\n1.1.1 Physical environment in fresh waters .................................................................... 3\n1.1.2 Chemical environment in fresh waters ................................................................... 4\n1.1.3 Biodiversity in fresh waters .................................................................................. 6\n1.2 Cyanobacteria Bloom ............................................................................................. 6\n1.2.1 Group and plankton ............................................................................................ 6\n1.2.2 Reproductive characteristics ................................................................................ 7\n1.2.3 Movement of cyanobacteria .................................................................................. 7\n1.2.4 Status in the biological chain ................................................................................ 8\n1.2.5 Toxicity of cyanobacteria ..................................................................................... 8\n1.2.6 Bloom ......................................................................................................... 8\n1.3 General cause of cyanobacteria blooms .......................................................................... 10\n1.3.1 Internal factors - biological characteristics of cyanobacteria ............................................... 10\n1.3.2 External factors- environmental conditions ................................................................... 11\n1.4 The harm of cyanobacteria ................................................................................... 13\n1.4.1 Consumption of dissolved oxygen in water ..................................................................... 13\n1.4.2 Reduce biodiversity .......................................................................................... 13\n1.4.3 Producing toxic and hazardous substances ..................................................................... 14\n1.5 Features of cyanobacteria..................................................................................... 14\n1.5.1 Overview of cyanobacteria photosynthesis ..................................................................... 14\n1.5.2 Reactive oxygen species (ROS) ........................................................................... 18\n1.5.4 Adaptation mechanism of cyanobacteria to environmental changes ............................................... 21\n1.6 Existing research .............................................................................................. 24\n1.6.1 Research on algae removal methods in countries around the world .............................................. 24\nCHAPTER 2 RESEARCH PURPOSES AND OBJECTIVES ................................................................. 27\n2.1 Research purposes ............................................................................................. 28\n2.2 Research objective ............................................................................................. 29\nCHAPTER 3 OXIDATIVE STRESS AND ANTIOXIDANT RESPONSES OF TWO CYANOBACTERIA SPECIES PHORMIDIUM AMBIGUUM AND \nMICROCYSTIS AERUGINOSA UNDER DIURNALLY VARYING LIGHT CONDITION ..................................................... 31\n3.1 Introduction ................................................................................................... 32\n3.2 Materials and Methods .......................................................................................... 34\n3.2.1 Cyanobacteria cultures and incubation ........................................................................ 34\n3.2.2 Experimental setup and procedure ............................................................................. 35\n3.2.3 H₂O₂ concentration ........................................................................................... 35\n3.2.4 GPX-activity assay ........................................................................................... 36\n3.2.5 CAT-activity assay ........................................................................................... 36\n3.2.6 APX-activity assay ........................................................................................... 37\n3.2.7 SOD-activity assay ........................................................................................... 37\n3.2.8 Data Analysis ................................................................................................ 37\n3.3 Results ........................................................................................................ 38\n3.4 Discussion ..................................................................................................... 51\nCHAPTER 4 EFFECTS OF LIGHT INTENSITY AND EXPOSURE PERIOD ON THE GROWTH AND STRESS RESPONSES OF TWO CYANOBACTERIA \nSPECIES: PSEUDANABAENA GALEATA AND MICROCYSTIS AERUGUNOSA .......................................................... 55\n4.1 Introduction ................................................................................................... 56\n4.2 Materials and Methods .......................................................................................... 58\n4.2.1 Cyanobacterial cultures and incubation ....................................................................... 58\n4.2.2 Growth experimental setup ................................................................................. 59\n4.2.2 Measuring Protein ............................................................................................ 59\n4.2.3 Measuring optical density (OD₇₃₀) ............................................................................ 60\n4.2.4 Measuring Chlorophyll-a concentations ........................................................................ 60\n4.2.5 Measuring H₂O₂ concentations ................................................................................. 60\n4.2.6 Measuring CAT activity ....................................................................................... 61\n4.2.7 Measuring POD activity ...................................................................................... 61\n4.2.8 Cell growth measurement and different model fitting .......................................................... 61\n4.2.9 Statistical analysis ......................................................................................... 63\n4.3 Results ........................................................................................................ 63\n4.4 Discussion ..................................................................................................... 73\nCHAPTER 5 INTERACTION OF PLANTS AND CYANOBACTERIA UNDER DIFFERENT LIGHT INTENSITY .................................. 76\n5.1 Introduction ................................................................................................... 77\n5.2 Materials and methods .......................................................................................... 79\n5.2.1 Plant material for culture and cuttings .......................................................................79\n5.2.1 Cyanobacteria culture ........................................................................................ 80\n5.2.2 Experiment setup ............................................................................................. 81\n5.2.3 Measurement of Egeria densa pigments ......................................................................... 82\n5.2.3 H₂O₂ and antioxidant enzyme quantification in Egeria densa ................................................... 83\n5.2.4 Chlorophyll fluorescence of Egeria densa ..................................................................... 84\n5.4 Discussion ..................................................................................................... 95\nCHAPTER 6 CONCLUSION AND FURTHER RESEARCH .......................................................................... 98\nReference ......................................................................................................... 101","subitem_description_type":"Other"}]},"item_113_description_25":{"attribute_name":"注記","attribute_value_mlt":[{"subitem_description":"主指導教員 : 藤野毅","subitem_description_type":"Other"}]},"item_113_description_33":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"subitem_description":"text","subitem_description_type":"Other"}]},"item_113_description_34":{"attribute_name":"フォーマット","attribute_value_mlt":[{"subitem_description":"application/pdf","subitem_description_type":"Other"}]},"item_113_dissertation_number_19":{"attribute_name":"学位授与番号","attribute_value_mlt":[{"subitem_dissertationnumber":"甲第1182号"}]},"item_113_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.24561/00019360","subitem_identifier_reg_type":"JaLC"}]},"item_113_publisher_11":{"attribute_name":"出版者名","attribute_value_mlt":[{"subitem_publisher":"埼玉大学大学院理工学研究科"}]},"item_113_publisher_12":{"attribute_name":"出版者名（別言語）","attribute_value_mlt":[{"subitem_publisher":"Graduate School of Science and Engineering, Saitama University"}]},"item_113_record_name_8":{"attribute_name":"書誌","attribute_value_mlt":[{"subitem_record_name":"博士論文（埼玉大学大学院理工学研究科（博士後期課程））"}]},"item_113_text_31":{"attribute_name":"版","attribute_value_mlt":[{"subitem_text_value":"[出版社版]"}]},"item_113_text_36":{"attribute_name":"アイテムID","attribute_value_mlt":[{"subitem_text_value":"GD0001272"}]},"item_113_text_4":{"attribute_name":"著者 所属","attribute_value_mlt":[{"subitem_text_value":"埼玉大学大学院理工学研究科（博士後期課程）理工学専攻"}]},"item_113_text_5":{"attribute_name":"著者 所属（別言語）","attribute_value_mlt":[{"subitem_text_value":"Graduate School of Science and Engineering, Saitama University"}]},"item_113_version_type_32":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"GULIGENA, MUHETAER","creatorNameLang":"en"},{"creatorName":"グリギナ, ムフタル","creatorNameLang":"ja-Kana"}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2021-09-16"}],"displaytype":"detail","filename":"GD0001272.pdf","filesize":[{"value":"3.2 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"GD0001272.pdf","objectType":"fulltext","url":"https://sucra.repo.nii.ac.jp/record/19391/files/GD0001272.pdf"},"version_id":"d2fc12df-a1e7-4066-b941-65c5100deba8"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"doctoral thesis","resourceuri":"http://purl.org/coar/resource_type/c_db06"}]},"item_title":"THE EFFECT OF DIFFERENT LIGHT INTENSITIES ON THE GROWTH AND STRESS RESPONSES OF CYANOBACTERIA","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"THE EFFECT OF DIFFERENT LIGHT INTENSITIES ON THE GROWTH AND STRESS RESPONSES OF CYANOBACTERIA","subitem_title_language":"en"}]},"item_type_id":"113","owner":"15","path":["992"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2021-09-16"},"publish_date":"2021-09-16","publish_status":"0","recid":"19391","relation_version_is_last":true,"title":["THE EFFECT OF DIFFERENT LIGHT INTENSITIES ON THE GROWTH AND STRESS RESPONSES OF CYANOBACTERIA"],"weko_creator_id":"15","weko_shared_id":-1},"updated":"2023-06-23T09:01:40.009741+00:00"}