BIOTRANSFORMATION OF 2-BENZOXAZOLINONE AND 6-METHOXY-BENZOXAZOLINONE BY FUSARIUM MONILIFORME

Authors: YUE, QIN - PLANT SCI, RUTGERS UNIV; Bacon, Charles; RICHARDSON, MICHAEL - PLANT SCI, RUTGERS UNIV

Submitted to: Phytochemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/1/1998
Publication Date: N/A
Citation: N/A

Interpretive Summary: The fungus Fusarium moniliforme grows within the living tissues of corn plants without producing any outward symptoms of a disease. However, the fungus in this state is producing at least 4 animal toxins, one of which enters the food chain via developing corn kernels. These kernels produce several toxicity syndromes in livestock and poultry. The problem is to prevent this common infection. Corn produces one group of natural fungus toxins, the cyclic hydroxamic acids. An RRC scientist in collaboration with his Research Associate established that the corn toxins do not have any effects on the growth of F. moniliforme, while it is toxic to other fungi. This RRC scientist in collaboration with his former Research Associate, and a natural product chemist, both from Rutgers University, have now determined that the fungus can detoxify these natural corn toxins. They further identified the decomposition products of the cyclic hydroxamic acids that they discovered are enzymatically detoxified. These findings are important because they provide the basis for studies of plant and fungus enzymes involved in the detoxification process of corn's natural defense, which may ultimately lead to molecular approaches for the control of this common toxic fungus of corn.

Technical Abstract: Fusarium moniliforme, a common fungal pathogen of corn, was previously shown to catabolize 6-methoxy-benzoxazolinone (MBOA) and 2-benzoxazolinone (BOA), biologically active compounds found naturally in corn. Studies were undertaken to isolate and identify the breakdown products of this reaction. For each benzoxazolinone, a novel acid was isolated from 48-hr old cultures of F. moniliforme by column chromatography that was monitored at 280 nm with a variable wavelength detector. MS, NMR, and IR data were used to identify the compounds as N-(2-hydroxyphenyl)-malonamic acid and N-(2-hydroxy-4- methoxyphenyl)-malonamic acid, products of BOA and MBOA, respectively.