Ylang-ylang Oil Research Articles

Molecular Structure and Gas Chromatographic Retention Behavior of the Components of Ylang-Ylang Oil

Using quantitative structure–retention relationships (QSRR) methodologies the Kovats gas chromatographic retention indices for both apolar (DB-1) and polar (DB-Wax) columns for 48 compounds from Ylang-Ylang essential oil were empirically predicted from calculated and experimental data on molecular structure. Topological, geometric, and electronic descriptors were obtained for model generation. Relationships between descriptors and the retention data reported were established by linear multiple regression, giving equations that can be used to predict the Kovats indices for compounds present in essential oils, both in DB-1 and DB-Wax columns. Factor analysis was performed to interpret the meaning of the descriptors included in the models. The prediction model for the DB-1 column includes descriptors such as Randic's first-order connectivity index (1X), the molecular surface (MSA), the sum of the atomic charge on all the hydrogens (QH), Randic's third-order connectivity index (3X) and the molecular electronegativity (χ). The prediction model for the DB-Wax column includes the first three descriptors mentioned for the DB-1 column (1X, MSA and QH) and the most negative charge (MNC), the global softness (S), and the difference between Randic's and Kier and Hall's third-order connectivity indexes (3X−3XV).

Complete1H and13C NMR Spectral Assignment of δ-Cadinene, a Bicyclic Sesquiterpene Hydrocarbon

δ-Cadinene from cade oil and ylang-ylang essential oil was independently analyzed by two research groups employing 2D NMR spectroscopy to effect the complete assignment of 1H and 13C spectra and to confirm the previously reported structure of δ-cadinene.

Fragrances Contact hypersensitivity to ylang‐ylang oil

Fragrances Contact hypersensitivity to ylang‐ylang oil

Differential Hypermelanosis Induced By Allergic Contact Dermatitis

In moderately colored guinea-pig skin, UVB, PUVA (psoralen plus UVA), and allergic contact dermatitis were shown to induce visibly well-defined hyperpigmentation that resembled the pigmentary changes observed in Mongoloid human skin. To clarify mechanisms of allergen-induced hyperpigmentation, we compared the effects of allergic contact dermatitis on pigmentation by using 6 different allergens: dinitrochlorobenzene (DNCB), 1-phenylazo-2-naphthol (PAN), benzyl salicylate (BS), jasmine oil (JO), hydroxycitronella (HC), and ylang ylang oil (YYO). The PAN-, JO-, HC-, and YYO-induced allergic reactions caused a definite visible hyperpigmentation that began to appear within 14 days, reaching maximum intensity about 40 days after the induction of the allergic reaction. These hyperpigmentations were accompanied by a significant increase in the population of dopa-positive melanocytes on day 24 following allergic reactions. In contrast, BS- and DNCB-induced allergic reactions did not give rise to visibly distinct hyperpigmentation in spite of the intensive allergic reactions following their challenge application. In a nonsensitized group, primary irritant reactions were induced by the application of 100% JO, but no distinctive hyperpigmentation was found 40 days after the last application. Quantitative analysis of the number of melanophages in the dermis showed that there was a marked increase in the number of melanophages in PAN, YYO, and HC allergy-induced hyperpigmented areas, with PAN showing a significant increase compared with those in non-treated areas of the same animals, whereas JO was associated with no such increase in hyperpigmented area, despite the stimulated pigmentation. In the case of the lack of induced hyperpigmentation, as seen in BS and DNCB allergy and JO irritation, there was also no substantial increase in the number of melanophages. Our findings indicate that allergic contact dermatitis is a unique melanogenic stimulant different from UV irradiation.

Analysis of the Volatile Components of Ylang-Ylang Oil by Gas Chromatography

Five samples of commercially available ylang-ylang oil were analyzed by gas chromatography. Of the various stationary liquid phases used, a 20% Ucon on Chromosorb P(w/w) gave consistently the best separation. The composition of extra, first, second, and third quality fractions and pure oil No. 123 was determined on the basisof relative retention times.