Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/13/2002
Publication Date: 1/18/2003
Citation: OLIVA, A., MEEPAGALA, K.M., WEDGE, D.E., HARRIES, M.D., HALE, A.L., ALIOTTA, G., DUKE, S.O. 2003. NATURAL FUNGICIDES FROM RUTA GRAVEOLENS L. LEAVES, INCLUDING A NEW QUINOLONE ALKALOID. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. 51(4):890-896. Interpretive Summary: Natural fungicide compounds were isolated from rue (Ruta graveolens). Seven compounds were found to have moderate to good activity against plant pathogenic fungi that are problems with horticultural crops. One of these compounds is a compound not previously reported in any other organism. One or more of these compounds could be used as lead compounds for a natural product-based fungicide for the horticultural market.
Technical Abstract: Bioassay-directed isolation of antifungal compounds from Ruta graveolens leaves yielded seven compounds (two furanocoumarins, four quinolone alkaloids, including one novel compound (1-methyl-2- 4-[3,4-(methylenedioxy)phenyl]hexyl]-4-quinolone), and one quinoline alkaloid). We also report the 1H and 13C NMR assignments of the new compound. Antifungal activities of the compounds, including some coumarins 7- hydroxy coumarin , 4- hydroxy coumarin and 7-methoxy coumarin which are known to occur in Rutaceae species, were evaluated by bioautography and microbioassay. Four of the alkaloids had moderate activity against Colletotrichum species, including a benomyl-resistant C. acutatum. These compounds and the furanocoumarins 5- and 8-methoxypsoralen had moderate activity against Fusarium oxysporum. The novel quinolone alkaloid was highly active against Botrytis cinerea. Phomopsis species were much more sensitive to most of the compounds, with P. viticola being highly sensitive to all of the compounds.