Characterization of an antifungal compound isolated from an antagonistic fungus Aspergillus terreus against phytopathogenic fungi

식물병원균 생육을 저해하는 Aspergillus terreus로부터 분리한 향균물질의 특성

An antagonistic fungus inhibiting growth of various phytopathogenic fungi was isolated from greenhouse soils and identified. Mophological features of fruiting structures on potato dextrose agar and colorless globose to ovate heavy walled hyaline cells from the vegetative mycelium grown on MY20 agar indicate that this antagonist is Aspergillus terreus. The antagonistic activity is due to the production of antifungal compounds. An antifungal compound was purified from its culture filtrate using chloroform extraction, column chromatography, and thin layer chromatography. The purified antibiotic was effective to various phytopathogenic fungi and identified as butyrolactone I. $ED_{50}$ values measured by petri-plate assay through effective dosage(ED)-probit analysis were 9.7, 13.7, 23.3, 42.6 and 102.7 ppm on Botrytis cinerea, Rhizoctonia solani, Pythium ultimum, Phytophthora capsici, and Fusarium oxysporum, respectively.

온실 토양으로부터 주요 작물 병원균의 생육을 억제하는 길항곰팡이를 분리, 동정하였고, 그 균이 분비하는 향균물질을 분리하여 활성을 petriplate assay로 검정했다. 길항균의 foot cell, 분생포자 및 MY20 배지상의 균사 등 형태학적 특징에 근거하여 이 균을 Aspergillus terreus로 동정하였다. A. terreus의 배양여액을 chloroform으로 추출하고, 그 추출물을 column chromatography와 thin layer chromatography로 향균물질을 순수분리하였으며, 화학구조는 butyrolactone I이었다. 이 물질의 주요 작물병원균에 대한 $ED_{50}$은 Botrytis cinerea, Phytophthora capsici. Pythium ultimum, Rhizoctonia solani, 그리고 Fusarium oxysporum에 각각 9.7, 42.6, 23.3, 13.7, 102.7 ppm으로 나타났다.