Ildefonsa Stagno d'Alcontres

On the Genuineness of Citrus Essential Oils. Part XXXV. Detection of Added Reconstituted Mandarin Oil in Genuine Cold-Pressed Mandarin Essential Oil by High Resolution Gas Chromatography with Chiral Capillary Columns

ABSTRACT A rapid method to detect the addition of reconstituted mandarin oils to natural mandarin essential oils is suggested. The method is based on the ratio of the two enantiomers of limonene determined by GC using an on-line coupling of non-chiral and chiral capillary columns. The ratio of (−)-limonene and (+)-limonene in the genuine mandarin oils was 2.2 to 97.8, while in reconstituted oils the same ratio was 13.4 to 86.6. Addition of reconstituted oils increases the ratio of (--) to (+)-limonene in genuine oils enabling the detection of additions of even 5% of reconstituted oils to genuine mandarin oils.

On the Genuineness of Citrus Essential Oils. Part XLIII. The Composition of the Volatile Fraction of Italian Sweet Orange Oils (Citrus sinensis (L.) Osbeck)

ABSTRACT The composition of the volatile fraction of Italian sweet orange oil obtained from blond and blood pulp fruits has been studied by GC and GC/MS. The study has been carried out on 190 genuine oils obtained by “Pelatrice” and “FMC in-line” industrial processing during the 1991–92 season. More than 55 components have been identified in the oil, with limonene (ca. 95%) as the main component. Because of the relatively high percentage of octanal and decanal found in the oil, the carbonyl compounds are the most important components of the oxygenated fraction. The results obtained establish that the quantitative composition of sweet orange oil shows peculiar variations in many components during the season and greatly depends on the isolation procedure and the kind of fruit processed. Oil produced by the “Pelatrice” method has a lower monoterpene content and a higher aldehyde and alcohol content than the oil produced during the same time period by “FMC” process. Also, blood oils generally show a higher mo...

Studies on the essential oil bearing plants of Bangladesh. Part VI. Composition of the oil of Ocimum gratissimum L.

The composition of the essential oil of Ocimum gratissimum L. obtained from plants originating from Bangladesh and from plants introduced into Bangladesh from India is reported. The oil obtained from plants native of Bangladesh can be classified as thymol-type according to its thymol content (58.2%), while the oil obtained from plants introduced from India can be classified as eugenol/ocimene type according to its content of eugenol (66.5%) and ocimenes (18.9%).

ItalianCitrusPetitgrain Oils. Part III. Composition of Sweet Orange Petitgrain Oil

The composition of Italian sweet orange petitgrain oil was studied by LC-GC/MS (ITD), GC/MS (quadrupole) and GC systems with SE-52 and Carbowax 20 M GC columns. Industrial samples and laboratory samples from leaves of the cultivars Valencia late, Biondo comune and Moro were analyzed. Sweet orange oils are characterized by a higher content of monoterpene hydrocarbons of which sabinene (38-49%) was the major component, and a lower content of oxygenated compounds than other Citrus petitgrain oils. Industrial samples of sweet orange petitgrain oil are often contaminated by other Citrus petitgrain oils. Because of the low value of sweet orange petitgrain oils little attention is paid to the selection of raw material to be distilled. Laboratory isolated oils show some differences in their composition, mostly for linalool and sesquiterpene hydrocarbons content. All orange petitgrain oils were characterized by the presence of alpha- and beta-sinensal, which are absent in other Citrus petitgrain oils.

Uruguayan Essential Oils. Part VIII. Composition of Leaf Oil of Hyptis floribunda Briq. ex Micheli (Labiatae)

Abstract Hyptis floribunda leaf oil, obtained by hydrodistillation, was analyzed by GC and GC/MS. Forty-three components were identified in the oil. The main components were germacrene B (40.2%), β-caryophyllene (9.9%), germacrene D (9.8%) and α-copaene (8.0%).

Constituents of the Cold-Pressed Oil of Faustrime, A Trigeneric Hybrid of Monocitrus australasica x Fortunella sp. x Citrus aurantifolia

ABSTRACT Faustrime oil, obtained by applying manual pressure on the rind of this trigeneric hybrid, was analyzed by LC, GC and GC/MS. Fifty-four components were identified in the oil. The main components were limonene (43.24%), citronellal (16.30%), γ-terpinene (11.76%), α-phellandrene (4.48%), terpinen-4-yl acetate (2.66%), piperitone (2.11%) and β-bisabolene (1.43%).