Biological Control of Phytophthora Blight of Red-pepper Caused by Phytophthora capsici.;III. Identification of the Antifungal Substances Produced by Pseudomonas sp. A - 183.

This study was carried out to identify the three antifungal substances isolated from the culture medium of Pseudomonas sp. A-183 which is antagonistic against Phytophthora capsici. The substance A and B showed positive reactions at the Molish test and Anthrone test, but negative one at the Fehling test, strongly suggesting that both substance A and B had nonreducing sugar frameworks. The substance C only exhibited the phenomenon of the UV induced fluorescence. From the qualitative analysis with the spectroscopic techniques such as UV, Mass, IR and NMR, the substance A and B were known to be composed to sugar and fatty acid, and showed a base peak of 171(m/e). It was identified that substance A was decanoic acid) and the substance B was decanoic acid). The substance C was identified as a phenazine from the results of qualitative analysis with the spectroscopic techniques such as UV, Mass, IR and NMR.