Study of the diffusion coefficient of solute-type extracts in supercritical carbon dioxide: Volatile oils, fatty acids and fixed oils

2016 ◽  
Vol 109 ◽  
pp. 148-156 ◽  
Author(s):  
Alexis López-Padilla ◽  
Alejandro Ruiz-Rodriguez ◽  
Guillermo Reglero ◽  
Tiziana Fornari
2018 ◽  
pp. 91-97
Author(s):  
Artyom Dmitrievich Ivakhnov ◽  
Kristina Sergeevna Sadkova ◽  
Alina Sergeyevna Sobashnikova ◽  
Tat'yana Eduardovna Skrebets ◽  
Mikhail Vladislavovich Bogdanov

Comparative researches of ways of oil extraction from the fulfilled fruits of cloudberries (Rubus chamaemorus) with application of hexane and supercritical carbon dioxide as solvents are executed. Optimization is performed and optimum conditions of supercritical fluid extraction of oil are defined with use of central composite design of 2nd order. Pressure of carbon dioxide of 350 atm, temperature 85 °C, duration of extraction of 80 min are the optimum conditions of carrying out of the process. The yield of oil is 9.0%. Quality key indicators of the received oil were defined. The difference between the oil received by the SKF-CO2 method and the oil received by hexane extraction consists in improvement of organoleptic properties, the raised share of the combined fatty acids at decrease of a share of the free acids and high content of unsaturated fatty acids. It is shown that supercritical carbon dioxide can be an alternative to the hydrocarbons which are traditionally used for these purposes.


Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1836
Author(s):  
Lijuan Han ◽  
Qingqing Han ◽  
Yongjing Yang ◽  
Honglun Wang ◽  
ShuLin Wang ◽  
...  

Characterization of the structure and pharmacological activity of Berberis dasystachya Maxim., a traditional Tibetan medicinal and edible fruit, has not yet been reported. In this study, central composite design (CCD) combined with response surface methodology (RSM) was applied to optimize the extraction conditions of B. dasystachya oil (BDSO) using the supercritical carbon dioxide (SC-CO2) extraction method, and the results were compared with those obtained by the petroleum ether extraction (PEE) method. The chemical characteristics of BDSO were analyzed, and its antioxidant activity and in vitro cellular viability were studied by DPPH, ABTS, reducing power assay, and MTT assay. The results showed that the maximum yield of 12.54 ± 0.56 g/100 g was obtained at the optimal extraction conditions, which were: pressure, 25.00 MPa; temperature 59.03 °C; and CO2 flow rate, 2.25 SL/min. The Gas chromatography (GC) analysis results showed that BDSO extracted by the SC-CO2 method had higher contents of unsaturated fatty acids (85.62%) and polyunsaturated fatty acids (57.90%) than that extracted by the PEE method. The gas chromatography used in conjunction with ion mobility spectrometry (GC–IMS) results showed that the main volatile compounds in BDSO were aldehydes and esters. BDSO also exhibited antioxidant ability in a dose-dependent manner. Moreover, normal and cancer cells incubated with BDSO had survival rates of more than 85%, which indicates that BDSO is not cytotoxic. Based on these results, the BDSO extracted by the SC-CO2 method could potentially be used in other applications, e.g., those that involve using berries of B. dasystachya.


2019 ◽  
Vol 7 (4.14) ◽  
pp. 221
Author(s):  
S. N. Ibrahim ◽  
K. A. Radzun ◽  
K. Ismail

Chlorella vulgaris is one of the promising microalgae strains that can produce high yield of bio-oils. The C. vulgaris was pretreated with microwave irradiation prior to extraction using supercritical carbon dioxide (SCCO2). Fourier transform infrared spectroscopy (FTIR) analysis showed microwave irradiation pretreatment does not affect the material composition of C. vulgaris. Scanning electron microscopy (SEM) of the microwave irradiation pretreated microalgae showed an agglomeration of the cells with the cells shape became distorted due to rupturing of the cell walls. Optimization of the SCCO2 process parameters (pressure, temperature and CO2 flow rate) was performed by using response surface methodology (RSM) with central composite design (CCD). Two factors significantly affecting the extraction yield were temperature and pressure. The model equation also predicted the optimum condition for the SCCO2 (without microwave pretreatment) at 70 , 5676 psi and 7 sL/ min while optimum condition for SCCO2 (microwave irradiation pretreatment) at 63 , 5948 psi and 10 sL/ min. High amount of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), -linolenic acid and palmitoleic acid were found in the extracted oil with microwave irradiation pre-treatment sample.  In addition, the polyunsaturated fatty acids (PUFA) content in the microwave irradiation pretreated oil was considerably low and is desirable for biodiesel production. 


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