CHARACTERIZATION OF THE SUCROSE ESTER FRACTION FROM NICOTIANA-GLUTINOSA

Investigation of green leaf cuticular chemicals revealed that several of the 65 Nicotiana species produced sucrose ester mixtures varying widely in both the composition of the acid moieties and the position of attachment of the acid moieties to the hydroxyl groups of the sucrose molecule. The sucrose ester (SE) fraction from one of the more interesting species, Nicotiana glutinosa, was examined in detail. The leaf surface chemicals of green, field-grown plants were removed with methylene chloride, and this whole leaf wash was partitioned between hexane/80% methanol-water to yield a crude SE fraction. Chromatography of the crude polar fraction on Sephadex LH-20 yielded two SE-containing fractions, designated fractions I and II SE. Fractions I and II SE were analyzed by capillary GC/MS after conversion to their trimethylsilyl (TMS), terf-butyldimethylsilyl (TBDMS), and peracetate derivatives. The acid distributions of the two SE fractions were determined by capillary GC analyses of the free acids, liberated by saponification. The fractions were also analyzed by fast atom bombardment mass spectrometry (FABMS) and 13C NMR. The structures of fraction I SE contained one acetic acid group esterified to the fructose moiety in addition to three other aliphatic acids on the glucose portion of the sucrose, while fraction II SE only contained three aliphatic acids esterified to hydroxyl groups on the glucose moiety of the sucrose molecule. © 1990, American Chemical Society. All rights reserved.