Isolation and Purification of New Antifungal Compounds from Cyanobacteria : 남조류에서 신규 항진균 물질의 분리

국문 초록 (Abstract)

단세포 남조류 Synechocystis sp. PCC6803와 Synechocystis sp. PCC6701, 다세포 사상남조류 Nostoc sp. PCC7120 에서 항진균작용을 보이는 새로운 대사물질 4종을 분리하여 각각을 AK-3, AK-5, AK-31과 AK-63으로 명명하였다. 분리된 항진균물질은 남조류 세포가 생산하는 대사물질로서 최종적으로 동결건조체의 0.24%의 AK-3, 0.15%의 AK-5를 얻었고, AK-31과 AK-63은 한 종에서 분리된 것으로 합하여 0.48%를 얻었다. 이 연구에서 분리된 항진균물질을 Aspergills spp. 10종을 포함하여 13종의 곰팡이로 항진균 작용을 알아본 결과, 분리된 4개의 항진균물질 모두 곰팡이 10 µg이상 사용시 항진균효과를 보여주었다.

목차 (Table of Contents)

• CHAPTER Ⅰ. INTRODUCTION 1
• 1.1. Overview 2
• 1.2. Literature Review 3
• 1.2.1. Antifungal Agent 3
• 1.2.2. Fungal Infection 9
• 1.2.3. Fungal Infection 15
• 1.2.4. Diversity of cyanobacterial peptides 19
• 1.3. Objectives 27
• 1.4. Reference 28
• CHAPTER Ⅱ. EFFETIVE PURIFICATION AND ISOLATION OF ANTIFUNGAL COMPOUNDS FROM CYANOBCTERIA 41
• 2.1. Abstract 42
• 2.2. Introduction 43
• 2.3. Materials and Methods 44
• 2.3.1. Cultivation of cyanobacteria 44
• 2.3.2. Fungal strains 46
• 2.3.3. In vitro antifungal activities 49
• 2.3.4. Determination of effective purificaion methods 49
• 2.4. Results and Discussion 53
• 2.4.1. Confirmation of antifungal activity 53
• 2.4.2. Optimization of the solvent extraction 58
• 2.4.3. Determination of effective purificaion methods from Synechocystis sp. PCC 6803 60
• 2.4.4. Identification of antifungal agents 66
• 2.5. Conclusion 76
• 2.6. Reference 78
• CHAPTER Ⅲ. IDENTIFICAION AND INCREASED PRODUCTION OF ANTIFUNGAL COMPOUND FROM CYANOBACTERIA 81
• 3.1. Abstract 82
• 3.2. Introduction 83
• 3.3. Materials and Methods 84
• 3.3.1. Cultivation of cyanobacterium 84
• 3.3.2. In vitro antifungal activity from purified compound 84
• 3.3.3. Encleased production of antifungal agent from nutrient-limited medium 85
• 3.3.4. Quantification of antifungal activity and identification of antifugal agent 86
• 3.4. Results and Discussion 89
• 3.4.1. Quantification of antifungal activity from the purified compound 89
• 3.4.2. Influence of nutrient starvation of Nostoc sp. PCC7120 99
• 3.4.3. Identification of purified antifungal compounds 110
• 3.5. Conclusion 127
• 3.6. Reference 129
• CHAPTER Ⅳ. CHARACTERIZATION OF ANTIFUNGAL COMPOUND AND EVALUATION OF ANTIFUNGAL EFFCT OF THE COMPOUND PURIFIED FROM CYANOBACTERIA 133
• 4.1. Abstract 134
• 4.2. Introduction 134
• 4.3. Materials and Methods 135
• 4.3.1. Purification of the antifungal compound 136
• 4.3.2. Evaluation of antifungal effect by microscopic observation 136
• 4.3.3. Characterization of Antifungal metabolites 137
• 4.4. Results and Disscussion 138
• 4.4.1. Confirmation of antifungal effects by the purified agent 138
• 4.4.2. Characterization of isolated metabolite 144
• 4.5. Conclusion 156
• 4.6. Reference 157
• CHAPTER Ⅴ. OVERALL DISCUSSION AND FUTURE WORKS 160