A. Kayhani; F. Sefidkon; A. Monfared
Abstract
Plant essential oils are used in a wide range of pharmaceutical, food, cosmetics and hygienic products. Satureja sahendica Bornm is an endemic aromatic plant in Iran. In traditional medicine, it has analgesic and anti-infection properties. Savory is used for treatment of chest discomfort, cough, wasting ...
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Plant essential oils are used in a wide range of pharmaceutical, food, cosmetics and hygienic products. Satureja sahendica Bornm is an endemic aromatic plant in Iran. In traditional medicine, it has analgesic and anti-infection properties. Savory is used for treatment of chest discomfort, cough, wasting and rheumatic pain. Previous researches showed that the main compounds of Satureja Sahendica essential oil were ρ-cymene, thymol, carvacrol and γ-terpinene. Since different drying and distillation methods affect oil yield and composition of aromatic plants, in this study, to investigate the effect of drying methods, the aerial parts of Satureja Sahendica were collected from Agricultural Research farm in Qazvin, at full flowering stage. The plant materials were dried by different methods (oven 30°C, oven 40°C, oven 50°C and shade). The essential oils of each treatment were obtained by hydro- distillation in three replicates. The oils were analyzed by capillary GC and GC/MS. Oil yield and the percentage of main components were compared statistically by Duncan's Multiple Range Test in SAS software. Results showed that oil yields, percentage of thymol and total phenolic compounds in essential oils were not different statistically in oven 30°C , oven 40°C and shade, but drying in oven 50°C produced lower oil yield. The percentage of thymol and total phenolic compounds was higher in oven 50°C. Statistical analysis showed that the oil yield obtained from hydro-distillation method (1/45%) was higher than that of the other two methods (at 1% level), while the highest values of thymol and carvacrol were obtained by steam distillation (at 5% level).
F. Nikkhah; F. Sefidkon; E. Sharifi Ashoorabadi
Abstract
The aerial parts of Thymus vulgaris were collected in three stages of plant growth (before flowering, at the beginning and full flowering stage) from Research Field of Shahid Beheshti University (Tehran) at spring. The plant materials were dried in shade and their essential oils were isolated by hydro-distillation ...
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The aerial parts of Thymus vulgaris were collected in three stages of plant growth (before flowering, at the beginning and full flowering stage) from Research Field of Shahid Beheshti University (Tehran) at spring. The plant materials were dried in shade and their essential oils were isolated by hydro-distillation in three replications. In addition, the essential oils of plant materials at full flowering stage were obtained by water-steam distillation and direct steam distillation. The oil yields were calculated based on dried weigh and compared by statistic analysis. The oils were analyzed by capillary GC and GC/MS. Statistic analysis showed different stages of plant growth and different distillation methods had significant effect on oil yield. The highest oil yield was obtained at the beginning of flowering (1.18% w/w). Among distillation methods, the highest oil yield was obtained by direct steam distillation (1.20%). Analysis and identification of components showed thymol, P-cymene and g-terpinene as main compounds in all samples. The percentage of thymol at the beginning and full flowering stage was the same, but at the beginning of flowering was lower. There was no remarkable difference between different distillation methods for producing thymol, but by hydro-distillation the thymol amount was little higher. Based on the results of this investigation it can be concluded that the beginning of flowering and hydro-distillation are the best for obtaining the higher oil content and thymol percentage.
