Essential Oil Composition of Myrtle (Myrtus communis) Leaves

Abstract

Nine cultivars of myrtle ( Myrtus communis) were analyzed for their leaf essential oil yield and composition during two seasons. The oil yield composition on leaf dry weight basis varied with the year of collection and the season ranging from 0.6 to 10.7 g·kg −1 in the different cultivars. The oils were analyzed by GC-MS for compound identification and by GC for quantitative determinations by comparison with authentic standards. The main components of the essential oils were α-pinene (366.8 to 816.8 g·kg −1 ); limonene (42.8 to 468.8 g·kg −1 ), 1,8-cineole (32.0 to 230.6 g·kg −1 ), linalool (0.8 to 110.3 g·kg −1 ), geranyl-acetate (12.4 to 99.2 g·kg −1 ). Other minor components were α-terpineol (1.6 to 44.4 g·kg −1 ), terpinolene isomer 1 (0.0 to 42.6 g·kg −1 ), linalyl-acetate (0.0 to 36.3 g·kg −1 ), α-humulene (0.0 to 19.6 g·kg −1 ), terpinolene-isomer 2 (0.0 to 14.9 g·kg −1 ), p-cymene (0.0 to 13.0 g·kg −1 ) and geraniol (0.0 to 12.4 g·kg −1 ). The total content of the other minor components was less than 10 g·kg −1 . All cultivars were suitable for hydro-alcoholic infusion production and, in spite of the minor oil yield, the leaves harvested in winter showed an essential oil composition quite similar to those from spring.

Chemical composition of essential oils of leaves and flowers from five cultivars of myrtle (Myrtus communisL.)

“…For this reason, myrtle domestication and cultivation was widely promoted in Sardinia (Italy) (50)(51)(52)(53)(54)(55), where the liqueur industry needs high quantity and quality of raw materials and natural populations were under the unsustainable pressure of uncontrolled harvests (2,53,54). Today the possibility to find myrtle biomass from cultivation of one or more selected cultivars may be useful also to produce essential oil with a high-quality standard and relatively constant composition, as demonstrated in a previous research where the leaf essential oils from nine cultivars were analyzed in winter and spring time of different years (30).…”

“…Mainly for the importance in the perfume and flavor industry, the chemical composition of myrtle essential oils was previously studied in leaves from different geographic areas (18)(19)(20)(21)(22)(23)(24)(25): Spain (26), Corsica (27), Sardinia (28)(29)(30), Tunisia (31)(32)(33), Iran (8,(34)(35)(36)(37), Italy (38,39), Algeria (40,41), Greece (42), Cyprus (43), Montenegro (9), Croatia (44); and in fruits (26,29,45). Less information is available on myrtle essential oil from flowers (13,26,44).…”

“…Essential oil from myrtle leaves belongs to two basic types: the cineoliferum type, rich in terpens (α-pinene and limonene) and terpenoid oxides (1,8-cineole); and the myrtenilacetatiferum type, rich in terpenic esters (terpenil acetate, linalyl-acetate, bornyl-acetate) and terpenoid oxides (1,8-cineole) (22,30).…”

Genetic diversity and population structure of wild Sardinian Myrtle (Myrtus communis L.) genotypes from different microclimatic areas

“…Beside its use as ornamental specie of the Mediterranean "maquis" (Bruna et al, 2007), myrtle is intensively exploited for the aromatic proprieties of berries and leaves (Mulas et al, 1998;Messaoud et al, 2006). Essential oil extraction, antioxidants and liquor production are only some of the food and pharmaceutical industries utilization of the myrtle leaves and fruits (Gardeli et al, 2008;Mulas, 2012;Mulas and Melis, 2011). Considering the economic importance of myrtle and the success of some food products such as the liquor, the request of raw material in processing industries is constantly growing.…”

“…As a consequence, a conservation program is required to supply the liquor and pharmaceutical industries plant material request and to preserve and contain the reduction of natural population's diffusion (Melito et al, 2013a;Mulas and Melis, 2011). The preservation of myrtle population's natural diversity represents a long term strategy for domestication and future cultivars selection.…”