Robert J. Horvat

Comparison of the Volatile Flower Oils of Nicotiana rustica and N. forgetiana

ABSTRACT The volatile constituents obtained by vacuum-steam distillation of the flowers of Nicotiana rustica and of N. forgetiana were profiled by capillary GC and characterized by GC/MS. Compounds comprising 74% of N. rustica flower oil and 72% of N. forgetiana flower oil were identified. Seventeen compounds were observed in N. rustica oil, with the alkaloid, nicotine (25.92%), and the sesquiterpene, aromadendrene (11.26%) being the major constituents. Of the 14 compounds observed in N. forgetiana oil, no constituents exceeded 10% of the total amount. Farnesyl acetone (4.97%), β-pinene (4.19%), acoradiene (3.81%) and (Z)-3-hexenyl acetate (3.97%) were present in highest concentrations. Twelve compounds were common to the oils of both species, although seven of these were aliphatic C21-C25 hydrocarbons. These hydrocarbons occurred in significantly greater amounts in N. forgetiana. (Z)-3-Hexenol was die only component found at a level exceeding 5% in both species.

Volatile Constituents from the Flowers of Nicotiana longiflora

ABSTRACT The volatile constituents obtained by vacuum-steam distillation of flowers of Nicotiana longiflora were characterized by capillary GC and GC/MS. Twenty-nine compounds, comprising 75% of the GC profile of volatiles, were identified. The three major constituents were the labdane alcohol, manool; the acyclic diterpene, neophytadiene; and 2,4-diphenyl-4-methyl-2(Z)pentene. The volatile concentrate exhibited an aroma characteristic of green bell peppers, attributable to the presence of minor amounts of the potent aroma compound, 2-methoxy-3-isobutylpyrazine, previously unreported in Nicotiana species.

Volatiles of Ripe Flowering Quince (Chaenomeles speciosa Nakai)

ABSTRACT The volatile components isolated from Flowering Quince fruit were analyzed by capillary GC and GC/MS. Nineteen compounds were identified of which hexanal, ethyl butyrate, (E)-2-hexenal, (Z)-3-hexenyl acetate, ethyl hexanoate, linalool, trans-linalool oxide (furanoid), cis-linalool oxide (furanoid), α-terpineol, ethyl octanoate, Edulan I, ethyl (Z)-4-decenoate and ethyl p-methoxybenzoate were the major constituents.

Volatiles of Ripe Asian Pears (Pyrus serotina Rehder)

ABSTRACT The volatile components isolated from five cultivars (cvs) of Asian pears were analyzed by capillary GC and GC/MS. Seventeen compounds were identified of which toluene, ethyl butyrate, hexanal, (E)-2-hexenal, ethyl hexanoate, α-farnesene, and C19H40 were the major constituents in most cvs.