Phytochemistry (extraction, identification and measurement of active components)
V. Abdossi; B. Tavakoli; A. Mehrafarin; H.A. Naghdibadi
Abstract
To evaluate the quantitative and qualitative characteristics of Echinophora platyloba DC. under the influence of different drying methods, an experiment was conducted in a completely randomized design with 12 treatments and three replications in 2019. The experimental treatments included fresh plant, ...
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To evaluate the quantitative and qualitative characteristics of Echinophora platyloba DC. under the influence of different drying methods, an experiment was conducted in a completely randomized design with 12 treatments and three replications in 2019. The experimental treatments included fresh plant, drying the plant in the shade and sun, drying the plant with an oven at three temperatures of 45, 55, and 65 °C, drying the plant with a vacuum oven at three temperatures of 45, 55, and 65 °C, and drying the plant with a microwave at three powers of 200, 400, and 600 W. The aerial parts of the plant was collected from the heights of Tuyserkan city in Hamedan province in June and was affected by the different drying methods. The essential oil was extracted by Clevenger apparatus and then its components were identified by GC-MS. The findings of this study showed that the different methods of plant drying had a significant effect on the percentage and all the components of essential oil. The microwave drying method at 400 W, despite not being suitable for preserving the secondary metabolites of the plant, caused the highest essential oil content. The shade-drying method, despite the long drying time, was the most suitable method for preserving the essential oil composition in E. platyloba. The essential oil percentage in this study ranged from 0.06% to 0.39% and the main essential oil constituents included trans-β-ocimene (34.16-57.52%), α-phellandrene (8.87-16.52%), cis-ocimene (1.69-4.57%), b-phellandrene (2.08-9.24%), p < /em>-cymene (1.53-5.05%), β-pinene (0.73-1.94%), a-pinene (1.83-5.15%), veloutone (0.39-3.78%), trans-carveol (0.38-1.92%), linalool (0.72-3.57%), and germacrene-D (1.67-4.91%).
Z. Azimzadeh; A. Hassani; M. Esmaiili
Abstract
Anise hyssop (Agastache foeniculum [Pursh] Kuntze) is a medicinal and perennial herb, belonging to the Lamiaceae family. The essential oil of this plant is a rich source of Methyl Chavicol, giving antifungal and antibacterial properties to this plant. To evaluate the effect of different drying methods ...
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Anise hyssop (Agastache foeniculum [Pursh] Kuntze) is a medicinal and perennial herb, belonging to the Lamiaceae family. The essential oil of this plant is a rich source of Methyl Chavicol, giving antifungal and antibacterial properties to this plant. To evaluate the effect of different drying methods on the essential oil content and composition of Anise hyssop, the leaves were harvested at full flowering stage and dried by four methods (shade drying, sun drying, oven drying at 40, 60 and 80°C, and microwave oven drying at 180, 360, 540, 720, and 900W) in a completely randomized design with four replications. The drying process was continued until the moisture content of samples reached around 0.11 based on dry weight. Dried leaves were subjected to hydro-distillation using a Clevenger type apparatus to extract the essential oil. The oil samples were analyzed by GC and GC/MS. Results showed that drying methods had significant effect on the drying time and essential oil content. Minimum (4 minutes) and maximum (64 hours) drying time were obtained at 900 W microwave power and shade drying, respectively. The highest (1.51%) and the lowest (0.56%) essential oil content were observed in shade drying and microwave drying in 900 W, respectively. The results of essential oil analysis showed Methyl Chavicol was the main component of essential oil ranging from 83.1% (shade drying) to 94.6% (microwave drying at 720W). Overall, the findings of this study showed that shade drying in spite of long drying time was the best drying method. However, oven drying at 40°C or microwave method in low powers is recommended when our goal is fast drying and achieving essential oil with high percentage of methyl chavicol.
P. Rezvani Moghaddam; A. Ghani; M. Rahmati; S. Mohtashami
Abstract
In order to study the effects of different drying methods including oven, microwave and ambient (shade condition) on drying time, essential oil content, antioxidant activity and phenol compound of two populations of Tarragon (Artemisia dracunculus L.), two separate experiments were carried out on two ...
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In order to study the effects of different drying methods including oven, microwave and ambient (shade condition) on drying time, essential oil content, antioxidant activity and phenol compound of two populations of Tarragon (Artemisia dracunculus L.), two separate experiments were carried out on two populations (Mashhad and Nishabur). The experiment was performed in a completely randomized design with three replications and 13 drying treatments (oven temperatures: 40, 50, 60 and 70 °C, six microwave powers: 100, 180, 300, 450, 600 and 900 w, shade drying and combination of drying with microwave (600 and 900 w) and shade drying). In addition, a comparison was performed between fresh sample and the mentioned treatments. Results showed that moisture content and measured active substances were different between studied populations. In both experiments, the longest drying time (about 30 hours and 32 h for Mashhad and Nishabur population, respectively) and the shortest drying time (about 5 minutes) was obtained at ambient temperature and 900 w microwave power treatments, respectively. In both experiments, the highest essential oil content (2.27 and 3.2% for Mashhad and Nishabur population, respectively) was obtained from fresh samples and then ambient temperature and microwave 900 w treatments. Essential oil content was decreased by increasing drying temperature. Essential oil content was in an average in all combination treatments. The highest antioxidant activity (82.5 and 81.8% in Mashhad and Nishabur population, respectively) was obtained by fresh samples while the lowest amount was obtained for Mashhad (60.7%) and Nishabur (53%) populations in ambient temperature and in 40°C oven dry, respectively. Maximum phenol compound was recorded for Mashhad population (165 mg GA/g DW) in 600 w microwave power and Nishabur population (524/7 mg GA/g DW) in 900 w microwave power, respectively.
Z. Rafiei; S.M. Jafari; M. Alami; M. Khomeiri
Abstract
The aim of the study was to investigate the effect of extraction through two methods of maceration and microwave-assisted extraction on phenolic compounds of olive leaves (Mishen cultivar) with solvents of water, 80% methanol and acetone. The highest total phenolic content (211.385±0.13 mg tannic ...
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The aim of the study was to investigate the effect of extraction through two methods of maceration and microwave-assisted extraction on phenolic compounds of olive leaves (Mishen cultivar) with solvents of water, 80% methanol and acetone. The highest total phenolic content (211.385±0.13 mg tannic acid/g extract) was related to the methanol extract produced by microwave-assisted extraction but acetone extracts gave the lowest amount for both methods. Comparing the extraction methods showed that MAE had higher extraction efficiency in all three tested solvents. Regarding antimicrobial activity of olive leaf extracts, we evaluated the bactericidal effects of different solvent extracts on Staphilococcus aureus, Salmonella typhi and Escherishia coli. In terms of S. aureus, the lowest minimum inhibitory concentration (MIC= 315 µg/ml) and. minimum bactericidal concentration (MBC= 2500 µg/ml) were observed with acetone extract in MAE and methanol extracts in both methods, respectively. As for E.coli the lowest MIC was 625 µg/ml and the lowest MBC (5000 µg/ml) was associated with water and methanol extracts in microwave-assisted extraction. In terms of S. typhi, the lowest MIC and MBC were 315 and 10000 µg/ml, respectively. To conclude, it was found that S. typhi was the most resistant bacteria against the extracts; in most cases MAE-produced extracts showed more antimicrobial activity compared to traditional-produced extracts.
M. Azizi; M. Rahmati; T. Ebadi; M. Hasanzadeh khayyat
Abstract
Field experiment was carried out at the Ferdowsi University Research Field, Mashhad, Iran during 2007-2008, to determine the effect of different drying temperatures, microwave powers and natural method (shaded and sunny area) in Chamomile (Matricaria recutita L., Asteraceae) essential oil content, chamazolene ...
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Field experiment was carried out at the Ferdowsi University Research Field, Mashhad, Iran during 2007-2008, to determine the effect of different drying temperatures, microwave powers and natural method (shaded and sunny area) in Chamomile (Matricaria recutita L., Asteraceae) essential oil content, chamazolene content, drying time and drying rate. The experimental design was completely randomized block design having three temperatures: 50, 60 and 70 °C, six microwave powers: 100, 180, 300, 450, 600 and 900w and drying in shaded and sunny area, replicated thrice. The drying process was continued until the mass of the sample reduced to a moisture content of about 0.10 on a dry basis or 10% on a wet basis. The results indicate that different treatments of drying had a significant effect on the drying time and rate and essential oil and chamazolene content. The maximum essential oil content obtained at drying by the lowest temperatures and drying in shaded area. Whereas, higher drying temperatures of oven and microwave powers and drying in sunny area decreased the essential oil content. Maximum chamazolene content obtained at microwave drying (except 100w power) and natural method. Minimum chamazolene content was obtained at drying by oven.
