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•Sustainable green technologies for liposome preparation.•Production of micro‐ and nano‐sized liposomes with narrow size distribution.•Supercritical fluids assisted methods improve ...liposome encapsulation efficiency.
Liposome possesses a great number of advantages and therefore they can be used for a variety of applications. Among other things, they can serve as useful drug carriers in preclinical and clinical trials. Supercritical fluids assisted technology is an appropriate method for liposome preparation because of its nontoxicity to the environment enables particle size manipulation and solvent-free production. Thus, the use of supercritical fluids (SCFs) provides advanced technology for liposome preparation and may become the dominant technology for their preparation in the future. This review discusses the classification of liposome and gives a short overview of their applications and conventional methods of preparation. Emphasis is placed on the use of various supercritical fluids assisted methods for liposome preparation and their advantages and disadvantages. The reader is also updated about recent developments in supercritical fluids assisted liposome production technology.
Astaxanthin and lutein, antioxidants used in nutraceutics and cosmetics, can be extracted from several microalgal species. In this work, investigations on astaxanthin and lutein extraction from
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) ...in the red phase were carried out by means of the supercritical fluid extraction (SFE) technique, in which CO₂ supercritical fluid was used as the extracting solvent with ethanol as the co-solvent. The experimental activity was performed using a bench-scale reactor in semi-batch configuration with varying extraction times (20, 40, 60, and 80 min), temperatures (50, 65, and 80 °C) and pressures (100, 400, and 550 bar). Moreover, the performance of CO₂ SFE with ethanol was compared to that without ethanol. The results show that the highest astaxanthin and lutein recoveries were found at 65 °C and 550 bar, with ~18.5 mg/g dry weight (~92%) astaxanthin and ~7.15 mg/g dry weight (~93%) lutein. The highest astaxanthin purity and the highest lutein purity were found at 80 °C and 400 bar, and at 65 °C and 550 bar, respectively.
The high-pressure phase behavior of the ternary system constituted by carbon dioxide + globalide + chloroform was studied. Experiments were conducted applying the synthetic-visual method in a ...variable-volume view cell at a mass ratios of globalide to chloroform of 0.5:1, 1:1, and 2:1, over a temperature range from 313.15 to 343.15 K, and pressures from 5.17 to 20.25 MPa. Phase transitions of vapor–liquid bubble point (VLE-BP), vapor–liquid dew point (VLE-DP), liquid–liquid (LLE), and vapor–liquid-liquid (VLLE) type were observed. Furthermore, through the P-w diagram, the phase behavior of the ternary system in chloroform free-basis was analyzed between 0.4250 to 0.9735 of carbon dioxide mass composition. It has been observed that high quantities of chloroform lead to lower transition pressures. Moreover, PT-diagrams efficiently displayed that higher pressures are necessary to achieve a single phase medium as temperature rises, which characterize LCST behavior. PR-vdW2 model was used to estimate binary interaction parameters. Additionally, the ternary system was compared with binary systems available in the literature. The data presented in this work provides necessary information for the optimization and improvement of poly(globalide) synthesis in supercritical media.
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•Data for the phase equilibrium of the ternary systems CO2 + globalide + chloroform.•Measured at temperatures from 313.15 to 343.15 K and pressures up to 20.25 MPa.•Experimental data were correlated using PR-EoS with vdW2 mixing rule.•Chloroform has been shown to be effective in decreasing phase transition pressures.
Plant‐derived natural dyes are used in a variety of formulated products, from food to cosmetics and pharmaceutics. In addition to their color, they also provide some bioactivity. While they are ...mostly analyzed with high‐performance liquid chromatography, supercritical fluid chromatography was also employed for several dye families, mostly for carotenoids and chlorophylls, and more recently for anthraquinones and flavonoids. These supercritical fluid chromatography methods are described in this review. Because the dyes have different structures and structural variations (polarity, isomers, etc.), the best chromatographic system to achieve their separation is not always the same. Hydrophobic stationary phases are preferred for the most hydrophobic dyes (chlorophylls and carotenoids) while polar stationary phases are preferred for the polar dyes (anthraquinones and flavonoids). Regarding the mobile phase composition, chlorophylls and carotenoids are best eluted with moderate proportions of co‐solvent in CO2 (about 40%), while the most polar glycosylated flavonoids require higher proportions of co‐solvent and acidic additives. Because dyes are colorful, ultraviolet‐visible detection is often sufficient, while mass spectrometry offers additional structural information. Furthermore, fundamental information can also be gained through chromatographic analysis of dyes: either solubility in supercritical fluids, in view of their extraction, or retention behavior providing an understanding of stationary phase properties.
The first step in the isolation and purification of bioactive compounds from plant material is extraction. Extraction of secondary metabolites such as phenolic acids and flavonoids is difficult due ...to their insoluble nature. While conventional extraction methods such as Soxhlet, heat reflux, and maceration are successful procedures in the extraction of bioactive compounds and the equipment involved in these methods are distinct from each other. An appropriate extraction technique that balances product quality, process efficiency, production costs, and environmentally acceptable methods should be used for the extraction of bioactive compounds from plant tissues. The application of innovative extraction methods in the food industries has been extensively investigated, due to increased consumer expectations for greener options that do not include hazardous chemicals, as well as industry concerns about sustainable, nontoxic extraction techniques. Innovative technologies, such as high hydrostatic pressure (HHP), ultrasound (US), pulsed electric field (PEF), supercritical fluid (SF), and others, are increasingly replacing the conventional methods. The use of novel and combined novel technologies increases extractability, resulting in yields with higher extraction rates. It also yields lower impurities in the final extract and preserves thermo-sensitive compounds, uses different inorganic solvents, and consumes low energy. The purpose of the present review is to evaluate the efficiency of the different conventional, novel, and combined novel technologies involved in the extraction of bioactive compounds from plant materials.
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•The various conventional techniques for extraction of bioactive compounds are reviewed.•The paper also reviewed the various novel technologies for extraction of bioactive compounds.•The focus of the paper is combined novel technologies for extraction of bioactive compounds.•Efficiency of the extraction process can be increased by combining two technologies.
The coupling of columns in sub/supercritical fluid chromatography presents a great opportunity for influencing the separation efficiency and extending the selectivity of the separation system. ...Combinations of different types of chiral stationary phases could positively affect the enantioresolution if single ones are complementary to each other. In this work, two superficially porous particle (2.7 μm) macrocyclic glycopeptide‐based columns, namely TeicoShell and NicoShell, were serially coupled and tested in sub/supercritical fluid chromatography for the first time. The influence of the column arrangement on the enantioseparation of structurally diverse biologically active compounds was examined. The obtained results showed how the column order crucially affected the enantioresolution of compounds tested, but the retention was negligibly affected in most cases. We also demonstrated that single TeicoShell and NicoShell columns are very promising towards the development of highly efficient and fast/ultrafast sub/supercritical fluid chromatography methods for structurally different chiral compounds. The optimized methods for sub‐minute enantioselective separation of certain biologically important compounds were proposed.
microalgae in the red phase can produce significant amounts of astaxanthin, lutein, and fatty acids (FAs), which are valuable antioxidants in nutraceutics and cosmetics. Extraction of astaxanthin, ...lutein, and FAs from disrupted biomass of the
red phase using carbon dioxide (CO₂) in supercritical fluid extraction (SFE) conditions was investigated using a bench-scale reactor in a semi-batch configuration. In particular, the effect of extraction time (20, 40, 60, 80, and 120 min), CO₂ flow rate (3.62 and 14.48 g/min) temperature (50, 65, and 80 °C), and pressure (100, 400, and 550 bar.) was explored. The results show the maximum recovery of astaxanthin and lutein achieved were 98.6% and 52.3%, respectively, at 50 °C and 550 bars, while the maximum recovery of FAs attained was 93.2% at 65 °C and 550 bars.
In this review, recent advances in greener technology for extracting natural bioactive components from plant origin sources are discussed. Bioactive compounds of plant origin have been defined as ...natural chemical compounds present in small amounts in plants. Researchers have shown interest in extracting bioactive compounds because of their human health benefits and characteristics of being eco-friendly and generally recognized as safe. Various new extraction methods and conventional extraction methods have been developed, however, until now, no unique approach has been presented as a benchmark for extracting natural bioactive compounds from plants. The selectivity and productivity of traditional and modern extraction techniques generally depend on selecting the critical input parameters, knowing the nature of plant-based samples, the structure of bioactive compounds, and good scientific skills. This work aims to discuss the recent advances in supercritical fluid extraction techniques, especially supercritical carbon dioxide, along with the fundamental principles for extracting bioactive compounds from natural plant materials such as herbs, spices, aromatic and medicinal plants.
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