Volatile Constituents of Peel and Leaf Oils from Citrus limettioides Tan.
Jorge A. Pino 1, Enrique Sauri-Duch 2, Luis Cuevas-Glory 2* Instituto de Investigaciones para la Industria Alimenticia, Carretera al Guatao km 3½, La Habana CP19200, Cuba 2 Instituto Tecnológico de Mérida, Av. Tecnológico km 4½, Mérida, Yucatán, CP 97118, MéxicoReceived 13 July 2009; accepted in revised form 19 February 2010
Abstract: The chemical composition of the volatile compounds of peel and leaf oils from Citrus limettioides Tan. cultivated in Yucatan Peninsula was studied by GC and GC-MS. Sixty and sixty-six compounds were identified in the peel and leaf oils, respectively. The chemical components of these oils showed marked differences inchemical composition. The most prominent compound in the peel oil was limonene (73.2 %), while in the leaf oil the major components were limonene (32.1 %), citronellal (21.7 %) and linalool (15.5 %). Key words: Citrus limettioides, Rutaceae, peel oil, leaf oil, limonene, citronellal, linalool. Introduction: Citrus L. belongs to the subfamily Aurantioideae of the Rutaceae. Plants of this genus aregenerally distributed in the tropical and subtropical zones of the Northern and Southern hemispheres, although some species are found in temperate regions. None is native to the western hemisphere 1. Both the taxonomy and phylogeny of Citrus are very complicated and controversial, mainly due to the sexual compatibility between Citrus and related genera, the high frequency of bud mutations, the longhistory of cultivation, and wide dispersion 2. One of them is Citrus limettioides Tan., commonly named “chinalima” (in Yucatan, Mexico) or sweet lime (in USA) 3. C. limettioides is a tree of 4-12 m tall, with rounded crown and regular branches, armed with axillaries spines. Leaves oblong, elliptic to ovate; petioles usually with a narrow oblanceolate wing, while flowers are solitary and veryfragrant. The fruit is subglobose, greyish-yellow to orange, with a particular flavor resembling the sweet lemon 4. A review of the literature reveals that the volatiles of this plant have not been the subject of previous studies. This paper presents analytical results of the volatile constituents *Corresponding author (Luis Cuevas-Glory) E- mail: < email@example.com >
Luis Cuevas-Glory et al. /Jeobp 13 (3) 2010 pp 292 - 296
of the peel and leaf oils from Citrus limettioides Tan. from Yucatan Peninsula (Mexico). Materials and methods: About 0.5 kg of sweet lime fresh fruits and leaves were collected in the Yucatan Peninsula. The fruit peel, including albedo and flavedo (370 g) were chopped into small pieces and the leaves (230 g) were hydrodistilled for 3 h in a Clevengertypeapparatus. The yield of volatile oils was 0.3 % and 0.4 % for peel and leaves, respectively. A Perkin-Elmer AutoSystem XL with a FID, equipped with an AT-5MS fused silica column (30 m x 0.25 mm x 0.25 μm) was used. Oven temperature was programmed as follows: 70°C for 2 min, to 250°C at 4°C/min. Carrier gas (He) flow rate was 1 ml/min. Injector and detector temperatures were kept at 250°C. Sampleinjection was with a split ratio of 1:10. Linear retention indices were calculated using n-paraffin standards. The quantitative analysis was made for internal normalization method of areas integration, without consider response factors for individual compounds. A Perkin-Elmer Clarus 500 was used with a same capillary column and temperature program as in the GC-FID technique was used. The detectoroperated in impact electron mode (70 eV) at 250°C. Detection was performed in the scan mode between 30 and 400 Daltons. A library search was carried out using the Wiley, NIST and in-house Flavorlib libraries. The mass spectra were also compared with those of reference compounds and confirmed with the aid of retention indices from published sources 5. Results and discussion: The composition of the...