Water as a green solvent combined with different techniques for extraction of essential oil from lavender flowers

Using water as a green solvent with a variable geometry makes use of physical and chemical phenomena that are fundamentally different from those applied in conventional extraction techniques such as hydro-distillation, steam distillation or solvent extraction. Advantages and drawbacks of using water as a solvent with different physical and chemical states have been compared. A total of ten extraction techniques: hydro-distillation (HD), steam distillation (SD), turbo-hydro-distillation (THD), salt-hydro-distillation (NaCL-HD), enzyme-hydro-distillation (Enzyme-HD), micelle-hydro-distillation (Micelle-HD), ultrasound-hydro-distillation (US-HD) or subcritical water-hydro-distillation (SW-HD), solvent-free microwave extraction (SFME) and microwave steam distillation (MSD) were used to extract the essential oil from lavender (Lavandula L.) and their results were compared. The quantity was measured by the yield of essential oil and the quality was evaluated using the oil composition especially the content of linalyl acetate, linalool and terpin-4-ol compared with the corresponding control sample: Hydro-distillation. For environmentally friendly of the process: extraction time, total energy consumption and CO2 emission were considered and compared with conventional hydro-distillation. The mechanism explaining the linalyl acetate degradation has been resolved by using COSMORS software. Based on the present experimental conditions, it is recommended that lavender oil may be produced preferably by steam distillation assisted by microwave extraction to reduce the by-product formation by various chemical reactions and to getbetter oil recoveries

Extraction of α-mangostin from <em>Garcinia mangostana</em> L. using alternative solvents: Computational predictive and experimental studies

International audienceThis study evaluated the performance of alternative green solvents, i.e. D-limonene, dimethylcarbonate (DMC), ethanol, ethyl acetate, ethyl lactate and methyltetrahydrofuran (MeTHF) compared to the petroleum based dichloromethane, for extraction of alpha-mangostin from Garcinia mangostana pericarps. The Hansen solubility parameters (HSPs) were used to explain the dissolution behavior of the solutes and solvents, and the conductor-like screening model for realistic solvation. The (COSMO-RS), a statistical thermodynamic approach based on the results of quantum chemical calculations for comprehending the dissolving mechanisms were used to predict the extraction prediction. On the basis of the Hansen analysis, dichloromethane was the most suitable solvent for extraction of alpha-mangostin. However, COSMO-RS analysis showed a higher solubility of alpha-mangostin in ethyl lactate, DMC, MeTHF, ethyl acetate and ethanol. Moreover, the experimental studies using a classical reflux extraction followed by a quantitative HPLC analysis of alpha-mangostin showed similar results to the predictive values from the COSMO-RS model. The alpha-mangostin levels extracted by ethyl lactate, DMC, MeTHF, ethyl acetate and ethanol were higher than those using dichloromethane and D-limonene. The results support the potential use of ethyl lactate, DMC, MeTHF, and ethanol as alternative green solvents for the preparation of alpha-mangostin extracts

Extraction by solvent using microwave and ultrasound-assisted techniques followed by HPLC analysis of Harpagoside from Harpagophytum procumbens and comparison with conventional solvent extraction methods

This research paper presents a quick and ecofriendly technique for the extraction of harpagoside (HS), the active marker of Harpagophytum procumbens (HP), along with a comparison with conventional methods so as to propose an efficient HPLC method. HP is widely used as an anti-inflammatory in phytotherapy. The quality control of the herbal drug and extract calls for a time consuming method of conventional extraction, which involves a high consumption of solvents. In this study, HP has been extracted using conventional ultrasound (UAE) and microwave (MAE)-assisted methods. The effects have been examined based on several parameters of HS extraction efficiencies. An HPLC method with a core-shell column was developed in order to calculate the HS in HP. The flowratewas reduced by 4. The method of validation used is specific, linear, precise and accurate. MAE and UAE saved solvent consumption, time and energy. It has, therefore, been found that the combined UAE-HPLC process is convenient and appropriate for the quality control of HP