ISOLATION AND STRUCTURAL IDENTIFICATION OF SUCROSE ESTERS FROM CORN SPURREY (SPERGULA-ARVENSIS) - INHIBITION OF SEED-GERMINATION

Polar as well as nonpolar extracts of Spergula arvensis (corn spurrey) were shown to cause inhibition of seed germination. The polar methyle ne chloride extracts were subjected to solvent partitioning and separa tions by a combination of silicic acid and Sephadex LH-20 column chrom atography. All chromatographic fractions were monitored by a proso-mil let seed germination assay, which resulted in the isolation of a group of sucrose esters (SE). The identity of the ester acids was determine d by gas chromatography (GC) of their butyl esters. Further characteri zation of the SE by GC-mass spectrometry of their trimethylsilyl deriv atives showed the presence of four different SE groups with two to sev en acyl groups attached to sucrose. The SE isomers in greatest abundan ce contained either octanoic or dodecanoic acid along with two smaller branched-chain acids (butanoic and pentanoic acids). All four SE grou ps were inhibitory to seed germination. This is the first report of SE outside the family Solanaceae.