ARS | Publication request: ISOLATION AND IDENTIFICATION OF HEXAKETIDES FROM A PIGMENTED MONOSPORASCUS CANNONBALLUS ISOLATE

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 12, 2004
Publication Date: June 28, 2004
Citation: Stipanovic, R.D., Zhang, J., Bruton, B.D., Wheeler, M.H. 2004. Isolation and identification of hexaketides from a pigmented Monosporascus cannonballus isolate. Journal of Agricultural and Food Chemistry. 52(13):4109-4112.

Interpretive Summary: The fungus Monosporascus cannonballus has caused severe production losses to muskmelon and watermelon in the U.S. Normally this fungus does not produce appreciable amounts of pigment except for a black substance known as melanin. Occasionally, however, the fungus undergoes a number of changes. For example, its ability to cause disease is greatly diminished and it is no longer able to produce the black substance melanin. Also, the altered fungal forms produce large amounts of yellow-to-brown pigments that are not made by healthy forms of the fungus. We have now identified five of these pigments. They have not previously been identified in M. cannonballus and their role in reducing disease severity is being investigated.

Technical Abstract: Monosporascus cannonballus has caused severe production losses to muskmelon and watermelon in the U.S. We have identified five colored metabolites from a pigmented isolate of this pathogen. Two of these (monosporascone and dehydroxyarthrinone) have been isolated from other fungi, and three (demethylcerdarin, monosporascol A and azamonosporascone) have not previously been reported. The spectral characteristics including the 1H-NMR and 13C-NMR of all compounds are reported.