Supercritical Extraction of Heracleum persicum Plant and Mathematical Modeling

Background: Supercritical CO2 is the most applicable solvent because of its unique properties such as; high selectivity, non-explosivity, non toxicity, low cost of purchasing and its unique critical points. The solubility of this solvent changed rapidly with only a small change in pressure and temperature especially in pressure. According to literatures, the method of supercritical extraction is the best technology for extracting sensitive constituents. Despite of numerous studies in the literature for extracting essential oil from plants, no studies can be found about this valuable medicinal plant by CO2 supercritical extraction method.

Method: In this study, the extraction of main medicinal constituents from Heracleum Persicum and mathematical modeling was done using supercritical carbon dioxide. The experimental data were investigated was analyzed by using gas chromatography (GC) and mass spectrometer chromatography (GC-MS) methods. The model of seed and bed, which includes three parameters of mass transfer, axial dispersion, and effective penetration coefficients, were used for modeling the extraction process. This model was used based on the equilibrium of the fluid phase and solid phase to communicate with the experimental data. Then the obtained yield of supercritical technology was compared with the hydro distillation method.

Results: The main extracted constituents of some different varieties of Heracleum by different methods and solvents have been determined. The extracted chemicals by supercritical fluid technology from the seeds of the Heracleum Persicum encompasses hexyl butanoate, octyl 2- methyl butyrate, octylisobutyrate and anethole which are so effective against epilepsy and has the most antibacterial, antiviral and antifungal effects. So supercritical fluid extraction is more selective than the other methods.

Conclusion: Extracting of essential oil and mathematical modeling from H. persicum were performed under different operating conditions of temperature, pressure, particle size and solvent flow rate. Experimental and modeling results showed that the operating parameters used in different conditions had a different effect on extraction efficiency and model parameters.