Medicinal plants contain active ingredients in one or some of their organs. Squalene is one of the active ingredients that prevent heart attacks and cardiovascular diseases and protect the body from some cancers. The aim of the present study was to investigate the presence of squalene in a number of medicinal plants. In this experiment, the plant oils were extracted and measured using Bligh & Dyer with minor changes. TLC (thin layer chromatography) was used to identify squalene. Comparison of TLC of standard squalene with TLC of the investigated medicinal plant samples showed that Caryophillium aromaticus, Descurainia sophia, Portulaca Oleracea, Papaver somniferum and Nigella Sativa contained squalene. Although the percentage of Papaver somniferum and Nigella Sativa seed oil was higher than other medicinal plants, the squalane spot of clove plant had a higher intensity of color and this indicates a higher concentration of squalene in this plant.

The hypothesis of the sufficiency of plant water content in extraction process was studied in theory. Essential oil extraction device was manufactured using a non-distillable gas instead of water vapor and evaluated quantitatively and qualitatively. The results of experiments on the manufactured device resulted in the optimum extraction mode using the air cycle and showed that the highest efficiency was obtained at lower speeds and higher air temperatures. Also the results showed that the extracted essential oil by new method in all states is less than the essential oil obtained with steam distillation. The results of analysis of samples using GC/MS showed that the percentages of the compounds in the samples obtained from the gas cycle and water distillation methods were different. For example, the percentage of limonene in the essential oil of Clevenger was 12. 24 and in the gas cycle method was 0. 22.

With respect to the influence of extraction method on the oil yield and essential oil composition, we examined three common methods of extraction (i.e. water and steam distillation, hydrodistillation and steam distillation) on the oil yield and essential oil composition of Eucalyptus camaldulensis Dehn from Iran. The oils were produced at the yields of 0.22, 0.60 and 0.60% (based on fresh weights), respectively. The essential oils were then analysed by GC and GC/MS. Twenty-two compounds were identified which among them 1,8-cineole (63.7,48.8,35.6%), pcymene ( 15.2,16.3,21.3%), spathulenol (3.9, 3.7, 6.7%) and g-terpinene (5.1,2.3,2.5%) were the major constituents, respectively.

This study was conducted to find the effects of fruit ripening and extraction method on the quantity and quality of the Koroneiki olive oil. The oil samples extracted in six ripening stages were used for further quality analysis. Quality assessment of the oil was conducted according to the standard methods and the composition of fatty acids was measured by gas chromatography. The results showed that there were some significant differences in the percentage of oil among different fruit tissues and harvesting times. In all tissues, the percentage of oil in dry matter increased significantly from 12 Oct to 4 Jan. The mesocarp and seed had significantly higher percentages of oil compared to endocarp. The extraction method and harvesting time had some significant influences on peroxide value. Furthermore, the extraction method showed a significant effect on the refractive index, but not on the other quality traits studied. The oil extracted using soxhlet had higher peroxide value, but lower refractive index compared to the oil extracted by centrifugation. The harvesting time showed some significant effects on the percentage of free fatty acids, K232 value, K270 value and the amounts of total chlorophylls and total carotenoids. There were a higher percentage of free fatty acids in the oil samples produced in later harvesting times. The oil extracted on 1 Mar showed the highest percentage of free fatty acids. On the other hand, the oil samples obtained from earlier harvesting times had higher values of K232 and K270 and higher amounts of total chlorophylls and carotenoids. The results showed an increase in the percentage of oleic acid and linoleic acid during the harvesting times; while, there was a slight decrease in the percentages of other fatty acids studied.

There are various methods available to assist in the oil extraction from oil seeds, one of which is the use of ultrasonic waves. In this research, in order to optimize the process of extraction of oil from the peanut using ultrasound pretreatment, three levels of sonication time (0, 30 and 60 min) were used. After using these pretreatments, the oil of seeds was extracted with screw press with different rotation speeds (11, 34 and 57 rpm), then parameters including oil extraction yield, acidity, oxidative stability, peroxide, total phenolic compounds and refractive index of the samples were studied. Statistical analysis and process optimization was performed with the use of response surface methodology (RSM). The results showed that with increasing sonication time, oil extraction yield and phenolic compounds increased first and then decreased. By increasing the speed of the screw press, the amount of oil extraction yield and oxidative stability decreased, but the acidity, peroxide and total phenolic compounds increased. Increasing the sonication time also resulted in increased acidity, oxidative stability and peroxide reduction. On the other hand, it was determined that the parameters did not affect the rate of refractive index and its rate was 1. 471 for all measured samples. According to the results of process optimization, it might be stated that with applying 60 minutes of ultrasound time and screw-rotation speed of the press of 21. 73 rpm can provide a 0. 766 utility for extracting oil from peanut.