2-hexenal--z-isomer and phenylacetaldehyde

Ranunculus nipponicus var. submersus is an aquatic macrophyte; it is known as a wild edible plant in Japan for a long time. In this study, the essential oils from the fresh and dried aerial parts of R. nipponicus var. submersus were extracted by hydrodistillation and analyzed by gas chromatography (GC) and GC-mass spectrometry (GC-MS). Moreover, important aroma-active compounds were also detected in the oil using GC-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). Thus, 98 compounds (accounting for 93.86%) of the oil were identified. The major compounds in fresh plant oil were phytol (41.94%), heptadecane (5.92%), and geranyl propionate (5.76%), while those of. Dried plant oil were β-ionone (23.54%), 2-hexenal (8.75%), and dihydrobovolide (4.81%). The fresh and dried oils had the green-floral and citrus-floral odor, respectively. The GC-O and AEDA results show that phenylacetaldehyde (green, floral odor, FD-factor = 8) and β-ionone (violet-floral odor, FD-factor = 8) were the most characteristic odor compounds of the fresh oils. β-Cyclocitral (citrus odor, FD-factor = 64) and β-ionone (violet-floral odor, FD-factor = 64) were the most characteristic odor compounds of the dried oil. These compounds are thought to contribute to the flavor of R. nipponicus var. submersus.

Topics: Acetaldehyde; Aldehydes; Alkanes; Chromatography, Gas; Distillation; Diterpenes; Gas Chromatography-Mass Spectrometry; Indicator Dilution Techniques; Japan; Norisoprenoids; Odorants; Oils, Volatile; Olfactometry; Phytol; Propionates; Ranunculus; Water

Attraction of the soybean pod borer, Leguminivora glycinivorella (Matsumura), an economically important pest of soybean, to nine plant volatiles, alone or combined with two kinds of synthetic sex pheromone, ((E,E)-8,10-dodecadienyl acetate (EE8,10-12:Ac), or a blend of EE8,10-12:Ac and (E)-10-dodecenyl acetate in a 10:1 ratio), was evaluated in field trapping experiments in a soybean field in Harbin, China. By themselves, the plant volatiles (dose) linalool (0.1 mg), (Z)-3-hexenyl acetate (0.1 mg), and geraniol (0.1 mg, 1.0 mg) were weakly attractive to L. glycinivorella males, but significantly reduced mean catches when higher doses were combined with pheromones. Conversely, (E)-2-hexenal, benzaldehyde, and phenylacetaldehyde were not attractive to L. glycinivorella males at any dose tested, but significantly increased mean catch when certain doses were combined with the binary pheromone blend. Other plant volatiles, such as (Z)-3-hexen-1-ol, (Z)-3-hexenyl acetate, and (E)-2-hexenyl acetate, were unattractive on their own, but significantly reduced mean catch of L. glycinivorella males when certain doses were combined with the pheromones. These results suggest that efficacy of pheromone-baited traps for survey and monitoring of L. glycinivorella male moths may be enhanced by the addition of specific plant volatiles and that the relative dose is critical.

Topics: Acetaldehyde; Acetates; Aldehydes; Animals; Benzaldehydes; Hexanols; Lepidoptera; Male; Sex Attractants