M. Naderi Hajibagher kandi; F. Sefidkon; A. Azizi; M.R. Pourheravi
Abstract
Laurus nobilis L. (Lauraceae) is an evergreen shrub widely distributed in the Mediterranean area and Southern Europe. Laurus nobilis is widely found in north of Iran and other places and its cultivation has been common due to evergreen leaves and beautiful appearance. Due to the relationship between ...
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Laurus nobilis L. (Lauraceae) is an evergreen shrub widely distributed in the Mediterranean area and Southern Europe. Laurus nobilis is widely found in north of Iran and other places and its cultivation has been common due to evergreen leaves and beautiful appearance. Due to the relationship between distillation time and oil yield and composition, doing research on optimum distillation time to obtain the best quality and quantity of essential oils with the lowest energy consumption has been always considered by scientists. In this study, the effect of different extraction times including 15, 30, 45, 60, 75, 90, 105 and 120 minutes on the essential oils content and composition of Laurus nobilis leaves was investigated. The leaves of laurus nobilis were collected in July 2009 from National Botanical Garden of Iran in Tehran, and dried in shade. The essential oil of leaves was extracted by hydro-distillation and analyzed by capillary gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The leaf oil yield based on dry weight in 15, 30, 45, 60, 75, 90, 105 and 120 minutes were respectively 1.35%, 1.92%, 1.97%, 2%, 2.37%, 2.49%, 2.58% and 2.60%. Statistical analysis showed no significant differences in oil yield of 90, 105 and 120 minutes extraction times. According to the results, with a view to quantity, 90 minutes was identified as the best extraction time for essential oil extraction in laurus nobilis. 1, 8-cineole and sabinene were identified as the major components of the leaf oil respectively within 15 minutes and after 45 minutes. α-terpinyl acetate remained constant in all extraction times.
Sh. Ne'mati; F. Sefidkon; M.R. Poorherave
Abstract
Thymus species are well known as medicinal plants because of having biological and pharmacological properties. Thymus daenensis is an endemic aromatic medicinal plant to Iran. Essential oil of Thymus daenensis is a rich source of thymol which gives high antimicrobial and antioxidant activity to this ...
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Thymus species are well known as medicinal plants because of having biological and pharmacological properties. Thymus daenensis is an endemic aromatic medicinal plant to Iran. Essential oil of Thymus daenensis is a rich source of thymol which gives high antimicrobial and antioxidant activity to this plant. In this research, the aerial parts of Thymus daenensis were collected at full flowering stage from Alborz Research Station in Karaj. For finding the effect of drying methods on essential oil yield and composition, the plant material were dried in four different conditions (oven 30°C, 40°C, 50°C and shade). After drying the samples, their essential oils were obtained by water distillation in three replications and were analyzed by GC and GC/MS. Oil yield and percentage of main components were statistically compared by Duncan's test in SAS software. Oil yields (w/w) of the oven-dried 30°C, 40°C, 50°C and shade-dried samples were 1.42%, 1.12%, 1.24% and 1.29%, respectively. Thymol (75.3%, 75.7%, 72.0% and 67.2%), allo-aromadendrene (5.7%, 5.2%, 5.4% and 3.9%), γ-terpinene (2.9%, 2.8%, 5.9% and 10.2%), p-cymene (4.2%, 4.1%, 5.1% and 5.5%) and carvacrol (2.2%, 4.1%, 1.6% and 2.4%) were identified as the main components in oven-dried 30°C, 40°C, 50°C and shade-dried samples, respectively. Statistical analysis showed a significant difference between oil yields of oven-dried 30°C sample with other samples. The highest percentage of thymol was obtained from oven-dried 30°C and 40°C that showed a significant difference with other drying methods.
M. Naderi Hagibaghercandi; F. Sefidkon; M.R. Poorherave; M. Mirza
Abstract
Laurus nobilis L. (Lauraceae) is an evergreen tree and growing in favorable condition to a height of about 15-20 meter. This ornamental tree is indigenous to the Mediterranean area and southeast part of Europe. The essential oil obtained from Laurus nobilis has been used for anti larvae, rheumatic pains ...
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Laurus nobilis L. (Lauraceae) is an evergreen tree and growing in favorable condition to a height of about 15-20 meter. This ornamental tree is indigenous to the Mediterranean area and southeast part of Europe. The essential oil obtained from Laurus nobilis has been used for anti larvae, rheumatic pains and muscular convulsion. Laurel is usually considered as the natural source of this compound, used in the flavor, cosmetic and fragrance industries. In the present study the leaves of Laurus nobilis were collected from two locations (Botanical Garden of Noshahr and National Botanical Garden of Iran in Tehran) in March 2009 and dried in shade. In addition the green stems and fruits were collected from Noshahr. The essential oil of all samples were obtained by hydro-distillation and analyzed by capillary gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The oil yields based on dry weight for stem, leaf and fruit are respectively 0.22%, 0.43% and 1.35% (for Noshahr samples) and 3.86% for the leaves of Tehran sample. Twenty-fore, 27, 37 and 20 components were identified in the essential oils of stem, leaf, fruit (for Noshahr) and leaf (for Tehran) of Laurus nobilis (representing 95%, 98.5%, 95.6% and 98.4% of the oils), respectively. The major components in the stem oil were 1,8-cineole (42.9%), α-terpinyl acetate (16.8%) and sabinene(4.7%). The main compounds in leaf oil were 1,8-cineole (58.2%), α-terpinyl acetate (10%) and sabinene(7.2%) and main compounds in leaf oil in Tehran sample were 1,8-cineole (47%), sabinene(13.9%) andα -terpinyl acetate (11.5%). The major components in fruit oil were E-β-ocimene (20.8%), 1,8-cineole (14.4%), α-terpinyl acetate (8.5%), germacrene B (7.8%), α-pinene (6.6%), germacrene D (6%), sabinene(5.4%) and β-pinene (5.1%). The results obtained from this study showed that the oil yields from the stem was lower than leaves but in both stem and leaf oils the major components were similar. The fruit oil contained high amount of E-β-ocimene.