Ionic Liquid-based Microwave-assisted Extraction Method Research Articles

A PREPARATION, CHARACTERIZATION, AND IN VITRO SKIN PENETRATION OF MORUS ALBA ROOT EXTRACT NANOEMULSION

Objective: White mulberry (Morus alba) root extract has terpenoid, flavonoid, and stilbene compounds. The stilbenes, oxyresveratrol and resveratrol, have antioxidant and antityrosinase activities. Nanocarriers can help active ingredients to be delivered in a more efficient manner. The advantages of nanoemulsion on products include increased penetration, biocompatibility, and low toxicity due to its non-ionic properties and have the ability to combine the properties of lipophilic and hydrophilic active ingredients. The objective of this study was to prepare, characterize, and evaluate the in vitro skin penetration of M. alba root extract nanoemulsion.
 Methods: The M. alba root extract was prepared by ionic liquid-based microwave-assisted extraction method. Nanoemulsion was optimized and prepared using virgin coconut oil (VCO), Tween 80, and polyethylene glycol 400 (PEG 400) by aqueous phase-titration method to construct pseudoternary phase diagram. M. alba root extract nanoemulsion was characterized for droplet size, viscosity, zeta potential, and physical stability tests for 12 weeks. In vitro skin penetration of oxyresveratrol from nanoemulsion was determined by the Franz diffusion cell and was compared by macroemulsion preparation, then analyzed by high-performance liquid chromatography method.
 Results: Based on pseudoternary phase diagram, nanoemulsion of white mulberry root extract contained of 2% VCO and 18% mixture of surfactant Tween 80 and PEG 400 (1:1) was chosen. Nanoemulsion has average globule size of 81.61 nm, with polydispersity index 0.22, and potential zeta −1.56 mV. The cumulative penetration of oxyresveratrol from nanoemulsion was 55.86 μg/cm2 with flux of 6.53 μg/cm2/h, while regular emulsion was 32.45 μg/cm2 with flux of 3.5501 μg/cm2/h.
 Conclusion: Nanoemulsion of white mulberry root extract was penetrated deeper than regular emulsion.

Rapid determination of oxindole alkaloids in cat's claw by HPLC using ionic liquid-based microwave-assisted extraction and silica monolithic column.

Cat's claw is a large woody vine with hook-like thorns, and has been traditionally used to treat inflammatory disorders in South and Central America. In this study, a rapid, validated high-performance liquid chromatographic (HPLC) method using a silica monolithic column was developed for the simultaneous determination of oxindole alkaloids, namely rhynchophylline, pteropodine, isomitraphylline and isopteropodine, in cat's claw. The ionic liquid-based microwave-assisted extraction (ILMAE), considered as an environmentally friendly and powerful tool, was first applied in the extraction of oxindole alkaloids. To optimize the HPLC method, the stationary phases, pH values of mobile phase and flow rates were investigated. The validated HPLC method using a Monolithic RP18e column (100 × 4.6 mm) enables these analytes to be separated almost twice as fast as with a conventional particulate column (~16 vs ~30 min) with limits of quantification and detection of 0.5 and 0.15 μg/mL, respectively. The ILMAE conditions were optimized by the Taguchi orthogonal array design. In comparison with conventional water boiling extraction, ILMAE offers almost four times higher yields within an extremely short extraction time. The developed HPLC coupled with ILMAE method could be efficient and practical for rapid determination of oxindole alkaloids in cat's claw.

Extraction of Polyphenolic Content from Peperomia pellucida (L) Kunth Herb with 1-Ethyl-3-methylimidazolium Bromide

Extraction of the polyphenolic content from Peperomia pellucida (L) Kunth herb (Piperaceae family) using 1-ethyl-3-methylimidazolium bromide as a solvent was attempted. The herbs were extracted using the ionic liquid-based microwave-assisted extraction method with some combination factors such as extraction time, microwave power, liquid-solid ratio, and ionic liquid concentration. The optimum yields of total polyphenolic content (13.750 µg GAE/g sample) were obtained by using a microwave power of 30 % Watt, extraction time of 10 minutes, the liquid-solid ratio of 14 ml/g, and ionic liquid concentration of 0.7 mol/l. Based on the results, compared to conventional organic solvent, the solvent of 1-ethyl-3-methylimidazolium bromide could provide higher extraction yields of polyphenolic content. Moreover, the extraction of a secondary metabolite from this herb becomes more rapid, easy, and efficient.

Optimization of ionic liquid-based microwave assisted extraction of a diterpenoid lactone-andrographolide from Andrographis paniculata by response surface methodology

Abstract An ionic liquid-based microwave assisted extraction (IL-MAE) method was developed for a diterpenoid lactone-andrographolide from Andrographis paniculata by response surface methodology using ionic liquid, 1-butyl-3-methyl-imidazolium chloride ([bmim]Cl). Variable microwave-assisted extraction parameters were selected as concentration of [bmim]Cl, extraction time and microwave power while solid-liquid ratio and extraction temperature were kept constant. Response surface methodology was employed to develop the predictive model for optimization and simulation of the extraction process. A multivariate quadratic regression equation was obtained by central composite design. The 3 D response surface curve and contour plots were obtained by variance of analysis (ANOVA). High performance thin layer chromatography (HPTLC) was performed for quantitative analysis of andrographolide and for comparison of IL-MAE extraction with conventional methods. The optimum extraction conditions were 2.84 mol/L, microwave power 600 W, extraction time 6 min, extraction temperature 70 °C, solid-liquid ratio 1:10. With this novel IL-MAE method, the yield of andrographolide was increased from 1.5% w/w in 7 days (maceration) and 1.8% w/w in 3 h (soxhlation) to 4.71% w/w in 6 min (IL-MAE). At the same time there was reduction in the environmental pollution by using the green solvents/ionic liquids (ILs).

Development of an ionic liquid-based microwave-assisted method for the extraction and determination of taxifolin in different parts of Larix gmelinii.

An ionic liquid-based microwave-assisted extraction method (ILMAE) was successfully applied for the extraction of taxifolin from Larix gmelinii. Different kinds of 1-alkyl-3-methylimidazolium ionic liquids with different kinds of cations and anions were studied and 1-butyl-3-methylimidazolium bromide was chosen as the optimal solvent for taxifolin extraction. The optimal conditions of ILMAE were determined by single factor experiments and Box-Behnken design as follows: [C4mim]Br concentration of 1.00 M, soaking time of 2 h, liquid-solid ratio of 15:1 mL/g, microwave irradiation power of 406 W, microwave irradiation time of 14 min. No degradation of taxifolin had been observed under the optimum conditions as evidenced from the stability studies performed with standard taxifolin. Compared with traditional solvent and methods, ILMAE provided higher extraction yield, lower energy and time consumption. The distribution of taxifolin in different parts of larch and the influences of age, orientation, and season on the accumulation of taxifolin were analyzed for the sufficient utilization of L. gmelinii.

Application of Ionic Liquids in the Microwave-Assisted Extraction of Proanthocyanidins from Larix gmelini Bark

Ionic liquid based, microwave-assisted extraction (ILMAE) was successfully applied to the extraction of proanthocyanidins from Larix gmelini bark. In this work, in order to evaluate the performance of ionic liquids in the microwave-assisted extraction process, a series of 1-alkyl-3-methylimidazolium ionic liquids with different cations and anions were evaluated for extraction yield, and 1-butyl-3-methylimidazolium bromide was selected as the optimal solvent. In addition, the ILMAE procedure for the proanthocyanidins was optimized and compared with other conventional extraction techniques. Under the optimized conditions, satisfactory extraction yield of the proanthocyanidins was obtained. Relative to other methods, the proposed approach provided higher extraction yield and lower energy consumption. The Larix gmelini bark samples before and after extraction were analyzed by Thermal gravimetric analysis, Fourier-transform infrared spectroscopy and characterized by scanning electron microscopy. The results showed that the ILMAE method is a simple and efficient technique for sample preparation.

Ionic liquid based microwave-assisted extraction of triazine and phenylurea herbicides from soil samples

The analysis of triazine and phenylurea herbicides in soil by ionic liquid based microwave-assisted extraction (IL-MAE) coupled with high-performance liquid chromatography was studied. The operational IL-MAE parameters were optimized, including types and concentration of ionic liquid, microwave power, irradiation temperature, extraction time and extractant volume. The results obtained under the optimized conditions were compared with methanol-MAE and IL-heating extraction, and it was determined that the IL-MAE method was rapid (4 min compared with 2 h for the heating extraction), efficient (recoveries were 1.6–12.2% higher than the other methods) and environmentally friendly (no volatile organic solvents were used). The proposed analytical method was evaluated by considering the average spike recoveries (84.0–101%) and relative standard deviations (2.8–6.0%), all of which indicate that the IL-MAE method is accurate, reproducible, and could be applied to real sample analyses.

Ionic liquid-based microwave-assisted extraction of essential oil and biphenyl cyclooctene lignans from Schisandra chinensis Baill fruits

Ionic liquid-based microwave-assisted extraction (ILMAE) has been successfully applied in extracting essential oil and four kinds of biphenyl cyclooctene lignans from Schisandra chinensis Baill. 0.25 M 1-lauryl-3-methylimidazolium bromide ionic liquid is selected as solvent. The optimum parameters of dealing with 25.0 g sample are 385 W irradiation power, 40 min microwave extraction time and 1:12 solid-liquid ratio. The yields of essential oil and lignans are 12.12±0.37 ml/kg and 250.2±38.2 mg/kg under the optimum conditions. The composition of the essential oil extracted by hydro-distillation, steam-distillation and ILMAE is analyzed by GC-MS. With ILMAE method, the energy consumption time has not only been shortened to 40 min (hydro-distillation 3.0 h for extracting essential oil and reflux extraction 4.0 h for extracting lignans, respectively), but also the extraction efficiency has been improved (extraction of lignans and distillation of essential oil at the same time) and reduces the environmental pollution. S. chinensis materials treated by different methods are observed by scanning electronic microscopy. Micrographs provide more evidence to prove that ILMAE is a better and faster method. The experimental results also indicate that ILMAE is a simple and efficient technique for sample preparation.