Cannabis Search Engine Series
Cannabis | CO2 Extraction | Oil Extraction | Supercritical CO2 Fluid Extraction search was updated real-time via Filemaker on:Cannabis | CO2 Extraction | Oil Extraction | Supercritical CO2 Fluid Extraction | Return to Search List
Search Completed | Title | Determination of extraction conditions of Ginkgo biloba L. leaves by supercritical CO2 using response surface methodology
Original File Name Searched: 06_3231_2011.pdf | Google It | Yahoo | Bing
Text | Determination of extraction conditions of Ginkgo biloba L. leaves by supercritical CO2 using response surface methodology | 001
Determination of extraction conditions of Ginkgo biloba L. leaves by supercritical CO2 using response surface methodology
Svetlana G. Milošević, Žika D. Lepojević, Zoran P. Zeković, Senka S. Vidović
Faculty of Technology, University of Novi Sad, Novi Sad, Serbia
The effects of process parameters on the extraction of Ginkgo biloba L. leaves with super- critical carbon dioxide were investigated. The investigated parameters include particle size (mean particle diameter 0.19, 0.467 and 1.009 mm), solvent flow rate (1.58×10–3, 3.22×10–3 and 4.16×10–3 kg CO2/min) and pressure (100–300 bar), which were obtained by the res- ponse surface methodology (RSM) under the following condition ranges: temperature 40– –50–60 °C, pressure 100–140–180 bar and extraction time of 2–3–4 h at the flow rate of 3.22×10–3 kg/min. Based on the experimental results of kinetics of Ginkgo biloba leaves extraction with supercritical carbon dioxide, modeling of the extraction system of Ginkgo biloba–supercritical CO2 was done. Two mathematical models (Reverchon–Sesti Osseo and Sovová) were applied to correlate the experimental data. RSM was applied to optimize the process parameters of supercritical carbon dioxide extraction of Ginkgo biloba L. leaves. A second-order polynomial response surface equation was developed indicating the effect of variables on Ginkgo biloba extraction yield. The statistical analysis of the experiment indi- cated that pressure (X1), extraction time (X3), the quadratic of temperature (X22), and the interaction between pressure and extraction time (X1X3), show significant effect on the extraction yield. The results showed that the data were adequately fitted into the second- order polynomial model. It was predicted that the optimum extraction process parameters within the experimental ranges would be the extraction temperature of 52.7 °C, the pres- sure of 184.4 bar, and the extraction time of 3.86 h. Under these conditions, the predicted extraction yield is 2.39% (g/100 g drug).
Keywords: Ginkgo biloba L.• supercritical extraction • supercritical CO2 • Response surface methodology
Hem. Ind. 65 (2) 147–157 (2011) doi: 10.2298/HEMIND101214010M
Available online at the Journal website: http://www.ache.org.rs/HI/
The dried leaves of Ginkgo biloba L. have been used as herbal remedies for centuries in China, and nowadays their extracts are one of the most widely used herbal products and/or dietary supplements in the world. Ginkgo biloba L. extract can reduce blood pressure, dilate peripheral blood vessels, increase ca- pillary and venous blood flow to the head and may be effective in treating peripheral arterial diseases, tinni- tus, hearing loss, inner ear neurological disorders, scle- rosis of cerebral arteries and intermittent claudication (poor circulation in the legs). It is helpful in inhibiting the onset of vascular dementia (including Alzheimer,s disease) and functional disability, and reducing the incidence of cardiovascular disease due to its ability to prevent free radical damage, improve brain function, and support microcirculation [1–5].
Ginkgo biloba leaves contain different active ingre- dients , such as ginkgolides (A, B, C and J), biloba- lides, flavonoids, flavonol aglycones, terpene trilakto-
Correspondence: S. Milošević, Department of Biotechnology and Pharmaceutical Engineering, Faculty of Technology, Cara Lazara 1, 21000 Novi Sad, Serbia.
Paper received: 14 December, 2010 Paper accepted: 14 February, 2011
nes, proanthocyanidins, alkylphenols, simple phenolic acids, etc. Ginkgo flavonoids are an important class of compounds in Ginkgo biloba leaves and usually act as scavengers of different oxidizing species, i.e., supe- roxide anions, hydroxyl, or peroxy radicals .
Ginkgo biloba extracts can be obtained using super- critical carbon dioxide extraction technology. In compa- rison to conventional extraction processes using liquid solvents, supercritical fluid extraction (SFE) is a good choice for the extraction of heat sensitive or easily oxi- dizable material. The application of SFE in the isolation and separation of natural products is becoming very popular due to the fact that the extraction is done without the addition of any toxic organic solvents.
At temperatures and pressures beyond the critical point, only the supercritical phase exists, whose pro- perties are close to those of liquid, but with greater dif- fusivity and lower viscosity. High diffusivity and low viscosity improve mass transfer and therefore help de- crease extraction time. Carbon dioxide is cheap, avail- able in a pure state, non-toxic and has an accessible critical point (31.1 °C and 7.38 MPa (72.9 atm; 73.8 bar; 1071 psi)).
Carbon dioxide is the most preferable supercritical fluid for extraction. Other substances, with easily acces-
Image | Determination of extraction conditions of Ginkgo biloba L. leaves by supercritical CO2 using response surface methodology
|Supercritical CO2 Fluid Extractor | Oil Extract Using Infinity Supercritical CO2 Extraction System - Botanical CO2 Extraction System - Go to website|
Search Engine Contact: firstname.lastname@example.org