Aqueous Two-phase Extraction Research Articles

Quantitative Analysis of Camellia oleifera Seed Saponins and Aqueous Two-Phase Extraction and Separation.

At present, the technology used for the extraction and purification of Camellia oleifera saponins generally has the problems of high cost and low purity, and the quantitative detection of Camellia oleifera saponins also has the problems of low sensitivity and easy interference from impurities. To solve these problems, this paper aimed to use liquid chromatography for the quantitative detection of Camellia oleifera saponins, and to adjust and optimize the related conditions. In our study, the average recovery of Camellia oleifera saponins obtained was 100.42%. The RSD of precision test was 0.41%. The RSD of the repeatability test was 0.22%. The detection limit of the liquid chromatography was 0.06 mg/L, and the quantification limit was 0.2 mg/L. In order to improve the yield and purity, the Camellia oleifera saponins were extracted from Camellia oleifera Abel. seed meal by methanol extraction. Then, the extracted Camellia oleifera saponins were extracted with an ammonium sulfate/propanol aqueous two-phase system. We optimized the purification process of formaldehyde extraction and aqueous two-phase extraction. Under the optimal purification process, the purity of Camellia oleifera saponins extracted by methanol was 36.15%, and the yield was 25.24%. The purity of Camellia oleifera saponins obtained by aqueous two-phase extraction was 83.72%. Thus, this study can provide a reference standard for rapid and efficient detection and analysis of Camellia oleifera saponins for industrial extraction and purification.

Sustainable extraction of ligustilide and ferulic acid from Angelicae Sinensis Radix, for antioxidant and anti-inflammatory activities

The 2030 Agenda for Sustainable Development envisions a rational use of energy and resources in all technological processes. However, in the extraction methods of compounds from medicinal plants and herbs, there is an urgent to reduce the use of organic solvents and increase the energy efficiency of these methods. Therefore, a sustainable extraction method (enzyme and ultrasonic co-assisted aqueous two-phase extraction, EUA-ATPE) of simultaneous extraction and separation of ferulic acid and ligustilide from Angelicae Sinensis Radix (ASR) was developed by integrating enzyme-assisted extraction (EAE) with ultrasonic-assisted aqueous two-phase extraction (UAE- ATPE). The effects of different enzymes, extraction temperature, pH, ultrasonic time, liquid-to-materials ratio, etc., were optimized by single-factor experiments and central composite design (CCD). Under the optimum conditions, the highest comprehensive evaluation value (CEV) and extraction yield were obtained by EUA-ATPE. Furthermore, recovery (R), partition coefficient (K), and scanning electron microscopy (SEM) analysis revealed that enzyme and ultrasonic treatment improved mass transfer diffusion and increased the degree of cell disruption. Besides, the EUA-ATPE extracts have shown great antioxidant and anti-inflammatory activity in vitro. Finally, compared to different extraction methods, EUA-ATPE achieved higher extraction efficiency and higher energy efficiency due to the synergistic effect between EAE and UAE-ATPE. Therefore, the EUA-ATPE provides a sustainable method for extracting bioactive compounds from medicinal plants and herbs, contributing to Sustainable Development Goals (SDG), including SDG-6, SDG-7, SDG-9, SDG-12, and SDG-15.

Scalable, Highly Pure, and Diameter-Sorted Boron Nitride Nanotube by Aqueous Polymer Two-Phase Extraction.

Boron nitride nanotube (BNNT) has attracted recent attention owing to its exceptional material properties; yet, practical implementation in real-life applications has been elusive, mainly due to the purity issues associated with its large-scale synthesis. Although different purification methods have been discussed so far, there lacks a scalable solution method in the community. In this work, a simple, high-throughput, and scalable purification of BNNT is reported via modification of an established sorting technique, aqueous polymer two-phase extraction. A complete partition mapping of the boron nitridespecies is established, which enables the segregation of the highly pure BNNT with a major impurity removal efficiency of > 98%. A successful scaling up of the process is illustrated and provides solid evidence of its diameter sorting behavior. Last, towards its macroscopic assemblies, a liquid crystal of the purified BNNT is demonstrated. The effort toward large-scale solution purification of BNNT is believed to contribute significantly to the macroscopic realization of its exceptional properties in the near future.

Extraction of Betacyanins from Hylocereus polyrhizus Peels Using Aqueous Two-Phase System

Hylocereus polyrhizus, known as red dragon fruit provides a betacyanin pigment source, which is not only concentrated in the flesh but also present in the peel with high content. Betacyanins are beautiful red-violet pigments used as food additives and stable in a wide pH range from 3 to 6. However, the stability of betacyanins is affected by heat, which causes discoloration. The aim of this work was to report the extraction of betacyanins from red dragon fruit peels by an aqueous two-phase system (ATPS) to overcome the drawback. By applying the aqueous two-phase extraction (ATPE) method on Hylocereus polyrhizus peels, the highest betacyanin yield of 85.07% was obtained in the optimal conditions of ammonium sulfate (12.75%, w/w); ethanol (30.00%, w/w); dragon fruit peel (8%, w/w), and pH 5.0 at 30 oC.

Aqueous two-phase extraction: A non-thermal technique to separate and concentrate betalains from Bougainvillea glabra Choisy bracts

The purple bracts of Bougainvillea glabra Choisy contain betalains that can be used as pigmenting agents. The objective was to evaluate the use of aqueous two-phase extraction systems to separate betalains from B. glabra bracts in order to improve the potential of this species as a source of natural pigments. A binodal phase diagram for the mixture of polyethylene glycol 4000 (PEG 4000) and trisodium citrate (Na3Cit; Na3C6H5O7) was studied to select betalain extraction conditions. The separation and concentration of betalains was evaluated and the feasibility of partitioning into betacyanins and betaxanthins was assessed. Mixtures of Na3Cit and PEG 4000 were prepared with concentrations in the ranges of 3.02–39.69% and 0.28–36.98%, respectively, and formed aqueous biphasic systems, with top phases composed mainly by PEG 4000 and bottom phases composed mainly by Na3Cit. The betalains showed a tendency to migrate towards the top phase, with an average separation yield of 92.41% and a concentration of 176.57 mg/L, while in the bottom phase an average content of 4.53 mg/L was found. Such situation was caused by a salting-out phenomenon and by a non-thermal concentration of compounds given by a reduction of the volume ratio between phases. The partition coefficient varied between 18.95 and 183.4 in betacyanins (Bc) and between 6.85 and 80.0 in betaxanthins (Bx). The Bc/Bx ratio varied between 2.82 and 3.26 in top phases and between 1.26 and 1.45 in bottom phases. The use of aqueous two-phase extraction systems allowed betalains to be separated and concentrated, although only a partial partitioning of Bc and Bx was achieved.

Single-walled carbon nanotubes synthesized by laser ablation from coal for field-effect transistors.

Single-walled carbon nanotubes (SWCNTs) have been attracting extensive attention due to their excellent properties. We have developed a strategy of using coal to synthesize SWCNTs for high performance field-effect transistors (FETs). The high-quality SWCNTs were synthesized by laser ablation using only coal as the carbon source and Co-Ni as the catalyst. We show that coal is a carbon source superior to graphite with higher yield and better selectivity toward SWCNTs with smaller diameters. Without any pre-purification, the as-prepared SWCNTs were directly sorted based on their conductivity and diameter using either aqueous two-phase extraction or organic phase extraction with PCz (poly[9-(1-octylonoyl)-9H-carbazole-2,7-diyl]). The semiconducting SWCNTs sorted by one-step PCz extraction were used to fabricate thin film FETs. The transformation of coal into FETs (and further integrated circuits) demonstrates an efficient way of utilizing natural resources and a marvelous example in green carbon technology. Considering its short steps and high feasibility, it presents great potential in future practical applications not limited to electronics.

Understanding the partitioning behavior of single-walled carbon nanotubes using an aqueous two-phase extraction system composed of non-ionic surfactants and polymers.

In this work, a Pluronic/Dextran system was developed to discover the mechanism of the aqueous two-phase extraction (ATPE) technique, which is widely employed for the sorting of single-walled carbon nanotubes (SWCNTs) and other types of nanomaterials. The role of the phase-forming components and partitioning modulators was comprehensively investigated to gain greater insights into the differentiation process. The obtained results revealed that sodium dodecyl sulfate and sodium dodecylbenzene sulfonate operated as excellent partitioning modulators, enabling the diameter-based sorting of SWCNTs. Additionally, the data strongly suggested that different densities of various SWCNT species drove the movement of SWCNTs in the ATPE system. Consequently, the largest diameter SWCNTs were first influenced by surfactants and, thus, the nanotubes migrated towards a lower density top phase in the following order (7,5) > (8,3) > (6,5) > (6,4). Based on the in-depth analysis of the partitioning system, a mechanism was proposed that described the method in which the popular ATPE separation technique operates.

An aqueous-two phase extraction system for partitioning of anthocyanins from red cabbage

An aqueous-two phase extraction system for partitioning of anthocyanins from red cabbage

Ultrasound assisted aqueous two-phase extraction of anthocyanins from blueberry and its anti-tumor activity

Blueberry contains abundant anthocyanins, polyphenols, polysaccharides, and other active compounds. Anthocyanins are one of the most principal active components in blueberry, which have high medical and medicinal values. Consequently, the aim of this paper is to optimize the ultrasound assisted aqueous two-phase extraction (UATPE) of anthocyanins from blueberry by response surface methodology (RSM). The optimal extraction process to achieve the highest yield of anthocyanins (5.96 ± 0.04) mg/g from blueberry via UATPE was obtained under the ultrasound power of 269 W, extraction temperature of 56 °C, ammonium sulfate mass fraction of 23 %, and ethanol concentration of 25%. Subsequently, we evaluated the anti-tumor activity of blueberry anthocyanins extract (BAE) obtained under the optimal process on breast cancer by MTT, confocal laser microscopy, and flow cytometer. The results show that BAE could memorably inhibit MCF-7 cells viability, increase the intensity of nuclear blue fluorescence, and accelerate the apoptosis of MCF-7 cells. The findings provide an effective and feasible method for the extraction of anthocyanins. Moreover, these results provide a material basis for the development of natural anti-tumor drugs.

Isolation of the (6,5) single-wall carbon nanotube enantiomers by surfactant-assisted aqueous two-phase extraction

Sorting single-chirality enantiomers is the ultimate goal for single-wall carbon nanotube (SWCNT) separation. In this work, aqueous two-phase extraction (ATPE) is used to obtain highly purified (>80%) left- and right-handed (6,5) SWCNTs with limited experimental steps. The optimized surfactant conditions are presented, and analytical ultracentrifugation (AUC) and near-infrared photoluminescence (PL) measurements are used to examine the surfactant wrapping and partition coefficient change conditions (PCCCs) required for separation. Our study provides valuable insights into the underlying mechanisms behind surfactant-assisted SWCNT separations and facilitates the use of SWCNT enantiomers in fundamental studies and applications in the future.

Theoretical Aspects and Applications of Aqueous Two‐Phase Systems

AbstractThe aqueous two‐phase system (ATPS) is commonly known as a technique that yields high‐purity products in a single step. It is particularly advantageous for purifying biomolecules like proteins, nucleic acids, enzymes, viruses etc. Currently, aqueous two‐phase extraction (ATPE), i.e., liquid‐liquid extraction, involves the transfer of the solute from one aqueous phase to another. In ATPE, for recovery of biomolecules, polymer‐polymer and polymer‐salt type systems are used. The most recent developments with respect to recovery of biomolecules by ATPS are reviewed and discussed, covering the mechanism, which controls the phase formation, the conditions of solute partitioning in ATPS processes, and factors influencing the ATPS including concentration and molecular weight (MW) of polymers, types of salt, pH, and temperature. In addition, also the increasing applications of ATPS for the recovery of high‐value bioproducts, the benefits of the ATPS recovery system, and the recent developments of alternative low‐cost ATPS are highlighted.

Synchronous Extraction, Antioxidant Activity Evaluation, and Composition Analysis of Carbohydrates and Polyphenols Present in Artichoke Bud.

This study investigated the optimization of ultrasonic-assisted aqueous two-phase synchronous extraction of carbohydrates and polyphenols present in artichoke bud, evaluated their antioxidant activities in vitro, and analyzed the composition of carbohydrates and polyphenols by high-performance liquid chromatography (HPLC). The powder mass, ultrasonic time, ammonium sulfate concentration, and alcohol-water ratio were considered the influencing factors based on the single-factor experiment results, and a dual-response surface model was designed to optimize the synchronous extraction process to extract carbohydrates and polyphenols. The antioxidant activity was evaluated by measuring the scavenging capacity of ABTS+· and DPPH· and the reducing capacity of Fe3+. The optimal process conditions in this study were as follows: the powder mass of 1.4 g, ammonium sulfate concentration of 0.34 g/mL, alcohol-water ratio of 0.4, and ultrasonic time of 43 min. The polyphenol content in artichoke bud was 5.32 ± 0.13 mg/g, and the polysaccharide content was 74.78 ± 0.11 mg/g. An experiment on in vitro antioxidant activity showed that both carbohydrates and polyphenols had strong antioxidant activities, and the antioxidant activity of polyphenols was stronger than that of carbohydrates. The HPLC analysis revealed that the carbohydrates in artichoke bud were mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, and arabinose, and the molar ratio was 10.77:25.22:2.37:15.74:125.39:48.62:34.70. The polyphenols comprised chlorogenic acid, 4-dicaffeoylquinic acid, caffeic acid, 1,3-dicaffeoylqunic acid, isochlorogenic acid B, isochlorogenic acid A, cynarin, and isochlorogenic acid C, and the contents were 0.503, 0.029, 0.022, 0.017, 0.008, 0.162, 1.621, 0.030 mg/g, respectively. This study also showed that the carbohydrates and polyphenols in artichoke bud could be important natural antioxidants, and the composition analysis of HPLC provided directions for their future research. Carbohydrates and polyphenols in artichoke buds can be separated and enriched using the optimized process technology, and it is an effective means of extracting ingredients from plants.

Isolation of papain from ripe papaya peel using aqueous two-phase extraction

Isolation of papain from ripe papaya peel using aqueous two-phase extraction

Evaluation of sources and methods of pectin extraction from fruit and Vegetable wastes: A Systematic Literature Review (SLR)

The potentially commercial sources of pectin are limited. Researchers have studied different extraction methods using a wide variety of fruits and vegetables to obtain pectins with better characteristics. The objective of this work was to identify the methods used in the extraction of pectin, the most used sources and the operation parameters that enable the achievement of higher yields and the final characteristics of the obtained product. These are based on bibliometric methods for exploring the structure of knowledge in this field for the last twelve years. To this end, a Systematic Literature Review (SLR) using the SCOPUS database was carried out, which allowed identifying keywords and formulating search equations to find scientific articles on the topic in question. After selecting the articles, a detailed reading of these works was carried out, and the used extraction methods and the evaluated variables, yields and characteristics were analyzed. This article compares and discusses the effects of conventional and non-conventional pectin extraction techniques, which may provide valuable information on sources and alternatives for pectin extraction to ease decision-making in future research. The acid hydrolysis method remains the most widely used pectin extraction technique since it provides higher yields. It is followed by microwave-assisted extraction, ultrasonic extraction, and the enzymatic method, which have a greater capacity to deliver pectins with high methoxyl content. Finally, non-conventional methods such as radiofrequency, ohmic heating, and aqueous two-phase extraction are presented as promising techniques that offer pectins with a high degree of esterification in addition to good yields.

Simultaneous extraction and preliminary purification of polyphenols from grape pomace using an aqueous two-phase system exposed to ultrasound irradiation: Process characterization and simulation.

In this study, an ultrasound-assisted aqueous two-phase (ATP) extraction method was used for the extraction and purification of phenolic compounds from grape pomace. The effect of acoustic energy densities (AED, 41.1, 63.5, 96.1, 111.2 W/L) and temperatures (20, 30, 40°C) on the yield of phenolics was investigated. An artificial neural network (ANN) was successfully used to correlate the extraction parameters with phenolic yield. Then, a diffusion model based on Fick's second law was used to model the mass transfer process during ultrasound-assisted ATP extraction and evaluate the effective diffusion coefficient of phenolics. The results revealed the increase in AED, and the temperature increased the effective diffusivity of phenolics. The HPLC analysis of anthocyanins and flavonols showed that ultrasound significantly increased the extraction yield of anthocyanins compared with the traditional method. High amounts of rutin and myricetin were recovered using the ATPS systems. Sugars were mainly distributed in the bottom phase, whereas phenolics were located in the top phase. Conclusively, ultrasound-assisted aqueous two-phase (ATP) extraction can be used as an effective method to achieve the simultaneous separation and preliminary purification of phenolics from grape pomace.

Optimization of ultrasound-assisted aqueous two-phase extraction of polysaccharides from seabuckthorn fruits using response methodology, physicochemical characterization and bioactivities.

Seabuckthorn fruits contains many active subtances, among them, the seabuckthorn polysaccharide is one of the main active ingredients, and exhibits diverse bioactivities. The extraction of polysaccharides from seabuckthorn fruits is the most important step for their wide applications. Ultrasound-assisted aqueous two-phase extraction (UA-ATPE) is a promising green method for extracting polysaccharides. Additionally, physicochemical characterization and antioxidant activities can evaluate the potential functions and applications in the food and medicine industries. Based on the single-factor experiments, 20.70% (w/w) ammonium sulfate ((NH4 )2 SO4 ) and 27.56% (w/w) ethanol were determined as the suitable composition for aqueous two-phase. The optimum conditions of UA-ATPE obtained by response surface methodology were as follows: ultrasonic power (390 W), extraction time (41 min), liquid-to-material ratio (72: 1mL/g), and the total yield of the polysaccharides reached 34.14 ± 0.10%, The molecular weights of the purified upper-phase seabuckthorn polysaccharide (PUSP) and the purified lower-phase seabuckthorn polysaccharide (PLSP) were 65 525 and 26 776 Da, respectively. PUSP and PLSP contained the same six monosaccharides (galacturonic acid, rhamnose, xylose, mannose, glucose and galactose), but with different molar ratios. Furthermore, PUSP and PLSP displayed certain viscoelastic property, had no triple helical structure, possessed different thermal stability, surface morphology and conformation in aqueous solution. PUSP and PLSP displayed strong antioxidant properties by the assays of scavenging ability of ABTS+ ·, the protection of DNA damage and erythrocyte hemolysis. UA-ATPE significantly increased the yield of seabuckthorn polysaccharides. PUSP and PLSP were different in many aspects, such as molar ratio, surface shape and antioxidant activities. Seabuckthornpolysaccharides possess great potential in medicine and functional foods. © 2022 Society of Chemical Industry.

Ultrasonic Enhancement of Aqueous Two-Phase Extraction and Acid Hydrolysis of Flavonoids from Malvaviscus arboreus Cav. Flower for Evaluation of Antioxidant Activity.

The ultrasonic-assisted aqueous two-phase extraction (UAATPE) of flavonoid glycosides from Malvaviscus arboreous Cav. flower (MACF) was developed using ethanol/ammonia sulfate systems, followed by the ultrasonic-assisted acid hydrolysis (UAAH) of the top extract with HCl solution. The optimization of UAATPE and UAAH processes was accomplished by single-factor experiments and response surface methodology. As a result, the flavonoid glycosides enriched in the top phase could achieve a maximum yield of 35.9 ± 1.1 mg/g by UAATPE and were completely hydrolyzed by UAAH deglycosylation. The flavonoid glycosides and their hydrolyzates were separated and characterized by high-performance liquid chromatography and ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. Ultrasonic enhancement of the extraction and hydrolysis was explored by comparative study. Furthermore, the in vitro activity of the flavonoid glycosides and the aglycones were comprehensively evaluated by antioxidant activity assays, including ferric-reducing antioxidant power and scavenging DPPH, hydroxyl, and superoxide radicals. All of the IC50 values suggest that the antioxidant activity of flavonoid aglycones was stronger than that of their glucosides and even vitamin C, revealing that the deglycosylated flavonoids from MACF were the more powerful antioxidants. This study provided an effective and eco-friendly strategy for the extraction, separation, and purification of flavonoids from MACF, as well as for the development of the potential flavonoid antioxidants.

Efficient isolation of biosurfactant rhamnolipids from fermentation broth via aqueous two-phase extraction with 2-propanol/ammonium sulfate system

The high production cost associated with environmentally unfriendly separation process significantly inhibit the real application of rhamnolipids in many fields. This study, for the first time, developed a green and efficient approach based on aqueous two-phase extraction by utilizing 2-propanol/(NH4)2SO4 to isolate rhamnolipids from the fermentation broth. After optimization, about 96% of the rhamnolipids were recovered from fermentation broth by employing aqueous two-phase extraction with 40% (v/v) 2-propanol and 200 g/L of (NH4)2SO4 at pH 5, with a purity of about 92%. Salts in the organic phase were then removed via re-generation of aqueous two-phase which resulted in a desalination ratio of over 95%. The present approach to extract rhamnolipids via aqueous two-phase extraction was also evaluated with fermentation broth produced by Pseudomonas aeruginosa PAO1 and 9027. This green and efficient separation process also enables the isolation of rhamnolipids from fermentation broth that cannot be precipitated under acidic conditions.

Characterisation and separation of infectious bursal disease virus-like particles using aqueous two-phase systems

Infectious bursal disease (IBD) causes considerable economic losses in the commercial poultry industry worldwide. The principal way to control IBD virus (IBDV), the causative agent of IBD, is still through vaccination programs. Virus-like particles (VLPs) are recognised as a safe and potent recombinant vaccine platform. This research work explores the characterisation and separation of infectious bursal disease virus-like particles (IBD-VLPs) from crude feedstock. Various characteristics were studied with high-performance size-exclusion chromatography (HP-SEC), sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE) and transmission electron microscopy (TEM) analyses. Subsequently, the separation of IBD-VLPs using polyethylene glycol (PEG)/sodium citrate-based aqueous two-phase systems (ATPSs) was conducted and optimised. Moreover, a scale-up study of the best ATPS constituted of 15% PEG 6000, 11% sodium citrate and 10% crude feedstock was performed to compare the separation performance of IBD-VLPs with and without centrifugation-assisted. The results indicated that the optimised ATPS with centrifugation-assisted for both 5 g and 50 g systems showed good recovery of IBD-VLPs of >97% in the interphase between the PEG-rich top and salt-rich bottom phases. These optimised systems also showed high removal efficiencies of impurities of >95%. The results demonstrated that aqueous two-phase extraction could be a promising technology for efficient VLPs separation.

Simultaneous Prediction, Determination, and Extraction of Four Polycyclic Aromatic Hydrocarbons in the Environment Using a UCON-NaH2PO4 Aqueous Two-Phase Extraction System Combined with High-Performance Liquid Chromatography-Ultraviolet Detection.

In this paper, a new aqueous two-phase extraction system(ATPES) consisting of UCON (poly(ethylene glycol-ran-propylene glycol) monobutyl ether)–NaH2PO4 was established, and four trace polycyclic aromatic hydrocarbons (PAHs: fluorene, anthracene, pyrene and phenanthrene) in water and soil were analyzed by high-performance liquid chromatography (HPLC)–ultraviolet detection. In the multi-factor experiment, the central composite design (CCD) was used to determine the optimum technological conditions. The final optimal conditions were as follows: the concentration of UCON was 0.45 g·mL−1, the concentration of NaH2PO4 was 3.5 mol·L−1, and the temperature was 30 °C. The recovery of the four targets was 98.91–99.84% with a relative standard deviation of 0.3–2.1%. Then UCON recycling and cyclic tests were designed in the experiment, and the results showed that the recovery of PAHs gradually increased in the three extractions because of the remaining PAHs in the salt phase of last extraction. The recovery of PAHs in the UCON recycling test was less than that in the extraction test due to the wastage of UCON. In addition, a two-phase aqueous extraction model was established based on the random forest (RF) model. The results obtained were compared with the experimental data, and the root mean square error (RMSE) was 0.0371–0.0514 and the correlation coefficient R2 was 96.20–98.53%, proving that the model is robust and reliable.