Pressurized Liquid Extraction Research Articles

Cochayuyo (Durvillaea incurvata) Extracts: Their Impact on Starch Breakdown and Antioxidant Activity in Pasta during In Vitro Digestion.

Seaweeds, notably cochayuyo (Durvillaea incurvata), are recognized for their rich macro- and micronutrient content, along with their inhibitory effects on the α-glucosidase enzyme. The present study aims to evaluate the effectiveness of this inhibition in actual starchy food products under in vitro gastrointestinal conditions. This study utilized freeze-dried cochayuyo, extracted using hot pressurized liquid extraction with 50% ethanol at 120 °C and 1500 psi. The inhibition mechanism of α-glucosidase was determined, and the polyphenol composition of the extract was analyzed using Ultra-High-Performance Liquid Chromatography. This study further evaluated the extract's impact on starch digestibility, total phenolic content, and antioxidant capacity in pasta (noodles) as representative starchy food under gastrointestinal conditions. The results indicate that the α-glucosidase inhibition mechanism is of mixed type. Phenolic compounds, primarily tetraphloroethol, could contribute to this anti-enzymatic activity. The extract was observed to decrease starch digestibility, indicated by a lower rate constant (0.0158 vs. 0.0261 min-1) and digested starch at an infinite time (77.4 vs. 80.5 g/100 g). A significant increase (~1200 vs. ~390 µmol TROLOX/100 g) in antioxidant activity was also noted during digestion when the extract was used. Thus, this study suggests that the cochayuyo extract can reduce starch digestion and enhance antioxidant capacity under gastrointestinal conditions.

Valorization of apple pomace by-products from the juice processing industry using pressurized liquid technology

Bagasse is a by-product of the juice processing industry with a high water content, high acidity, and rapid deterioration. Considering apple pomace, approximately 21 million tons are produced annually, rich in dietary fiber, vitamins, reducing sugars, and phenolic compounds. In this sense, conventional extraction (CE) and pressurized liquid extraction (PLE) were compared in terms of pectin yield, total phenolic compounds, and Ferric ion Reducing Antioxidant Power (FRAP) using a Box-Behnken factorial design considering the variables temperature, pressure, and Solvent/Feed (S/F) ratio. CE occurred with citric acid solution 6.5% (w/v) under stirring for 2 h. PLE occurred continuously with a flow rate of 5 mL min−1 with citric acid solution 6.5% (w/v) for 40 min. The highest pectin yield was 20.05% at 110 °C, 20 MPa, and S/F 10. Further optimized conditions led to a total phenolic compounds yield of 16.3 ± 0.3 mg GAE g−1 and FRAP of 137 ± 5 µmol TE g−1. Although pectin yield was higher for EC (25.27 ± 1.78%), total phenolic compounds content and FRAP were higher for PLE. High contents of glucose and fructose were found in all extracts. However, only high temperatures facilitated the hydrolysis and release of ellagic acid. Furthermore, a kinetic study demonstrated that 91.94% of total pectin was extracted with 11.30 min by PLE. Statistical analysis indicated that the effect of the linear and quadratic terms of the variable S/F ratio was significant for all responses evaluated. Therefore, the design approach efficiently obtained high pectin yields, providing information that allows expansion to pilot and industrial scales.

Evaluation of heavy metals, mycotoxins and mineral bioaccessibility through in vitro static digestion models of rainbow trout (Oncorhynchus mykiss) and sole (Dover sole) side stream extracts obtained by pressurized liquid extraction.

The recovery of antioxidants and minerals as well as the content of contaminants of rainbow trout and sole side streams (head, skin and viscera) extracts obtained by pressurized liquid extraction (PLE) were evaluated. Then, the effect of the gastrointestinal digestion was tested. No mycotoxins were detected in the extracts, while heavy metals contents (mg/kg) were up to 2.9 (As), 0.054 (Cd), 0.16 (Hg) and 0.073 (Pb), being below maximum legislated limits. A positive effect of PLE was found for the antioxidant capacity recovery, being the oxygen radical capacity of sole head and skin extracts significantly enhanced after digestion (∼3.8 times). PLE significantly increased Mg, Fe, Zn, Se and P (KPLE>1) contents of rainbow trout side streams, Zn (KPLE5.97) and Fe (KPLE 2.80) of head sole and Mg, Se and P of all samples. Moreover, Mg, Ca and Fe bioaccessibility was lower in all sole extracts compared to rainbow trout.

Pressurized Liquid Extraction (PLE) in an Intermittent Process as an Alternative for Obtaining Passion Fruit (Passiflora edulis) Leaf Hydroalcoholic Extract (Tincture)

Tinctures are medicinal plant extracts obtained by extraction with a hydroalcoholic solution (70%) by percolation (PER). This process takes about 26 h to prepare, in addition to using a large amount of solvent. In our research, passion fruit leaf tinctures were obtained using extract with the same pressurized hydroalcoholic solution as in an intermittent process. The objective was to demonstrate that this emerging technology can be economical and profitable. An optimization using Central Composite Rotatable Design (CCRD) was performed to evaluate the influence of process variables on the yields and compositions of the extracts. The temperature (T) was the factor that most influenced the responses. Extraction with pressurized liquid (PLE) provided total yields and total phenolic and flavonoid contents in greater amounts than PER. The optimized conditions of the process variables studied in the CCRD for the highest content of total phenolics (43.2 mg GAE/g) and flavonoids (58.8 mg QE/g) were at 100 °C with a rinse volume of 120% of the divided extractor volume in four cycles of the intermittent process. When adjusting the PLE in an intermittent process, and according to the one-dimensional mass transfer by the continuous diffusion of the Fick model, the effective diffusion coefficient (1.28 × 10−12 m2/s) was not affected by T. The kinetic curve of PLE extraction indicates that the adjusted intermittent process occurred in the period of the constant extraction rate when compared to the kinetics of the semi-continuous process. The yielded extracts were rich in isovitexin, and the highest levels were identified in the extracts obtained via PLE, indicating that this intermittent process can bring a product to market with the same quality but with a much shorter production time and the use of fewer solvents. Antioxidant activity, determined by DPPH, FRAP and ORAC, was also higher in extracts obtained via PLE.

Evaluation of Eugenia uniflora L. leaf extracts obtained by pressurized liquid extraction: Identification of chemical composition, antioxidant, antibacterial, and allelopathic activity

Pitangueira (Eugenia uniflora L.) leaves are rich in phenolic compounds. To evaluate these compounds, pitangueira leaves were submitted to extraction by aqueous infusion (AI) and by pressurized liquid extraction (PLE). PLE extracts were obtained with water (PLE-W), water:ethanol (PLE-W:E), and ethanol (PLE-E). Fifty-four extracted compounds were tentatively identified by LC-MS. The PLE-W:E extraction resulted in a higher concentration of phenolic acids and tannin compounds, while PLE-E showed a higher concentration of flavonoids. All extracts tested in vitro showed good antioxidant activity, as evaluated by thiobarbituric acid reactive substances (TBARS) and reactive oxygen species (ROS) assays in rat brain homogenates model systems and in protecting yeasts under oxidation. Among the eight bacterial strains tested with the pitangueira leaf extracts, antibacterial activity was observed mainly against Staphylococcus aureus with the extracts of AI, PLE-W, and PLE-W:E. And for Pseudomonas aeruginosa, only the AI extract showed antibacterial activity. The other strains were not affected by the extracts. All extracts exhibit an allelopathic effect against lettuce seeds. Even though 72.2% of the putatively identified compounds were common to all extracts, PLE extracts provide more regular antioxidant, antibacterial, and allelopathic activities.

Enhanced Polyphenols Recovery from Grape Pomace: A Comparison of Pressurized and Atmospheric Extractions with Deep Eutectic Solvent Aqueous Mixtures.

Deep eutectic solvents (DES) are emerging as potent polyphenol extractors under normal atmospheric conditions. Yet, their effectiveness in hot pressurized liquid extraction (HPLE) must be studied more. We explored the ability of various water/DES and water/hydrogen bond donors (HBDs) mixtures in both atmospheric solid liquid extraction (ASLE) and HPLE (50%, 90 °C) for isolating specific polyphenol families from Carménère grape pomace. We assessed extraction yields based on total polyphenols, antioxidant capacity, and recovery of targeted polyphenols. The HBDs ethylene glycol and glycerol outperformed DES in atmospheric and pressurized extractions. Ethylene glycol exhibited a higher affinity for phenolic acids and flavonols, while flavanols preferred glycerol. Quantum chemical computations indicated that a high-water content in DES mixtures led to the formation of new hydrogen bonds, thereby reducing polyphenol-solvent interactions. HPLE was found to be superior to ASLE across all tested solvents. The elevated pressure in HPLE has caused significant improvement in the recovery of flavanols (17-89%), phenolic acids (17-1000%), and flavonols (81-258%). Scanning electron microscopy analysis of post-extraction residues suggested that high pressures collapse the plant matrix, thus easing polyphenol release.

Post Acid Treatment on Pressurized Liquid Extracts of Sorghum (Sorghum bicolor L. Moench) Grain and Plant Material Improves Quantification and Identification of 3-Deoxyanthocyanidins

Sorghum is a unique natural food source of 3-deoxyanthocyanidins (3-DA) polyphenols. This work evaluated the effect of acidification on sorghum extracts post pressurized liquid extraction (PLE) and its ability to increase the identification and quantification of 3-DA. The sorghum genotypes included Sumac and PI570366 (bran only) and SC991 (leaf and leaf sheath tissue). The acidification of the PLE extracts was carried out with methanol–HCl solutions at various concentrations (0, 0.5, 1, 2, and 4%, v/v). Changes in color were determined using L*a*b*. The overall phenolic composition was estimated with the total phenolic content and the DPPH free radical scavenging assays. Quantitative and qualitative chromatographic methods determined the phenolic profile. Color analysis showed that the redness and color saturation increased after acidification. No statistical difference was found in the total phenolic content of the acidified extracts, except for SC991, which was increased. There were no differences in the antioxidant capacity following acidification in all samples. For chromatographic analysis, luteolinidin was predominant in the extracts and the 3-DA content increased after acid treatment. However, some flavonoid and phenolic acid concentrations decreased following acid treatment, including taxifolin, quercetin, and chlorogenic acid. Interestingly, 0.5% v/v HCl acidification was sufficient to increase the color, allow the detection of 5-methoxyluteolinidin, and to increase luteolinidin and 7-methoxyapigenidin by at least twofold.

EXPLORING APPROACHES FOR INVESTIGATING PHYTOCHEMISTRY: METHODS AND TECHNIQUES

The extraction, isolation, and analysis of bioactive compounds from plants are fundamental in the study of medicinal plants. This review explores various techniques and methods used for the extraction, isolation, and analysis of bioactive compounds from plant materials. Traditional methods such as maceration, percolation, and Soxhlet extraction are commonly used, but novel techniques have emerged to enhance efficiency and selectivity. Microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), pressurized liquid extraction (PLE), supercritical fluid extraction (SFE), and enzyme-assisted extraction are modern approaches that offer improved yields and efficiency. After extraction, bioactive compounds need to be characterized and analyzed. Chromatographic techniques, such as high-performance liquid chromatography (HPLC) and gas chromatography (GC), are commonly employed for separation and quantification. Spectroscopic techniques, including nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS), provide valuable structural information. The continuous development of extraction and analytical techniques contributes to the discovery and utilization of bioactive compounds from plants in various applications. Future research can explore metabolomics, high-throughput screening, chemoinformatics, network pharmacology, multivariate data analysis, and computational modeling to enhance phytochemical investigations. The proposed methods and techniques complement traditional approaches, expanding our understanding of plant chemistry and its potential applications.

Determination of sterols in rapeseed by pressurized liquid extraction with gas chromatography–tandem mass spectrometry

The cholesterol, cholestanol, brassicasterol, ergosterol, campesterol, stigmasterol, β-sitosterol, and stigmastanol content of rapeseed was determined herein. The sterols were isolated after derivatization and determination using pressurized liquid extraction coupled with gas chromatography–mass spectrometry. The results revealed a good linear relationship between the peak area and the corresponding mass concentration of the eight sterols in the range of 2–1000 mg/L, with correlation coefficients greater than 0.9991, detection limits of 1.12–1.52 mg/kg, quantification limits of 3.73–4.98 mg/kg, and satisfactory mean relative recoveries determined at 5–20 mg/kg and 200–1000 mg/kg. The mean relative recoveries were 92.5–104 % at the mg/kg supplemental level, and the precision was under 4.8 %. The developed method was efficient, simple, and accurate, suitable for the qualitative and quantitative analysis of sterols in rapeseed and providing a method for their rapid determination.

Development of a Methodology for Determination of Dioxins and Dioxin-like PCBs in Meconium by Gas Chromatography Coupled to High-Resolution Mass Spectrometry (GC-HRMS)

An analytical strategy was applied to investigate polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs) in newborn meconium samples. The methodology includes extraction by selective pressurized liquid extraction (SPLE), followed by a clean-up multicolumn step. The samples were injected by gas chromatography coupled to a high-resolution mass spectrometer (GC-HRMS). The surrogate recoveries ranged from 68% to 95%, and the average of the limit of quantification (LOQ) ranged from 0.03 to 0.08 pg g−1 wet weight (ww) for PCDD/Fs and 0.2 to 0.88 pg g−1 ww for dl-PCBs. The strategy was applied to 10 samples collected in Valencia (Spain) in 2022. In total, 18 out of 29 analysed congeners were detected in at least one sample, whereas 6 of them were detected in all the samples (OCDD, PCB-123, PCB-118, PCB-105, PCB-167, and PCB-156). The levels for the sum of the 17 congeners of PCDD/Fs and 12 congeners of dl-PCBs in the upper-bound (UB), expressed as picograms of toxic equivalency quantity (TEQ) per gram of ww, ranged from 0.19 to 0.31 pg TEQ g−1 ww.

Polysaccharides from the Sargassum and Brown Algae Genus: Extraction, Purification, and Their Potential Therapeutic Applications.

Brown macroalgae represent one of the most proliferative groups of living organisms in aquatic environments. Due to their abundance, they often cause problems in aquatic and terrestrial ecosystems, resulting in health problems in humans and the death of various aquatic species. To resolve this, the application of Sargassum has been sought in different research areas, such as food, pharmaceuticals, and cosmetics, since Sargassum is an easy target for study and simple to obtain. In addition, its high content of biocompounds, such as polysaccharides, phenols, and amino acids, among others, has attracted attention. One of the valuable components of brown macroalgae is their polysaccharides, which present interesting bioactivities, such as antiviral, antimicrobial, and antitumoral, among others. There is a wide variety of methods of extraction currently used to obtain these polysaccharides, such as supercritical fluid extraction (SFE), pressurized liquid extraction (PLE), subcritical water extraction (SCWE), ultrasound-assisted extraction (UAE), enzyme-assisted extraction (EAE), and microwave-assisted extraction (MAE). Therefore, this work covers the most current information on the methods of extraction, as well as the purification used to obtain a polysaccharide from Sargassum that is able to be utilized as alginates, fucoidans, and laminarins. In addition, a compilation of bioactivities involving brown algae polysaccharides in in vivo and in vitro studies is also presented, along with challenges in the research and marketing of Sargassum-based products that are commercially available.

Globe artichoke leaf extracts and production of phytotherapeutic solid lipid particles using high pressure technologies

The ethanolic extract of artichoke leaves is phytotherapic. Impregnation is used to protect the bioactive material and is also a means of controlling the release of the encapsulated substance while masking unwanted taste and/or color. This research describes a study of artichoke leaf extraction by five techniques and tested the formations of solid-lipid microparticles of beeswax and avocado oil loaded with these extracts by PGSS and their particle stability. Pressurized liquid extraction (PLE) using an intermittent process was optimized and presented the highest content of active compounds in the extracts, although the inulin contents (IC) were higher in the extracts obtained by conventional methods. Two different ratios between solid and liquid lipids and the extract (1:2:3 and 1:2:6; w:w:w) were studied. The particles with a major beeswax ratio showed a smaller distribution and average size (74.2 ± 6.2 µm), but no differences were observed in relation to stability. All extraction techniques were able to yield inulin (max. 173.46 ± 1.27 mginulin/gextract), and with PLE only the temperature had a significant effect on the extraction yield under the studied conditions.

Extraction of valuable compounds from granadilla (Passiflora ligularis Juss) peel using pressurized fluids technologies

Valuable products, including carotenoids, phenolic compounds, and pectin were obtained from granadilla peel using green technologies based on pressurized fluids. The processes of pressurized liquid extraction (PLE) and CO2-expanded ethanol (GXE) were evaluated to recover the carotenoids and phenolic compounds, while pressurized hot water extraction (PHWE) was evaluated to extract pectin from the granadilla peel. The results demonstrated that although PLE and GXE had no significant difference in the carotenoids yield and antioxidant activity of the extracts obtained, PLE was faster than GXE to achieve the highest extraction yield. The pectin yield obtained by PHWE was affected by the process temperature with the highest value obtained at 160 °C. Further studies are needed to characterize the chemical composition of the pectin obtained, but the present results enable establishing a biorefinery for the complete use of granadilla wastes (seeds and peel).

Isolation of Natural Compounds with Organoleptic Properties Using Selected Advanced Extraction Techniques

This review presents an overview of various advanced solid–liquid extraction techniques used for extraction of compounds with organoleptic properties from natural sources. These compounds are important additives to food, cosmetic, and pharmaceutical products. The most frequently used techniques are ultrasound assisted extraction and microwave assisted one, but there are other efficient techniques, such as pressurized liquid extraction, supercritical fluid extraction, pulsed electric field and enzyme assisted extraction. These techniques reduce or eliminate the volume of toxic solvents required for extraction, decrease the extraction time and mostly are more energy efficient. Low energy extraction conditions (pulsed electric field and enzyme assisted) can better preserve the compounds sensitive to heat, pH, and light.

Application of an integrative system (2D PLE×HPLC-PDA) for bioactive compound extraction and online quantification: Advantages, validation, and considerations

Analyzing compounds such as polyphenols in solid samples frequently uses a solid-liquid extraction step. The solid-liquid extraction and analysis integration in a single equipment is not commercially available since several challenges are inherent to this hybridization. In the context of developing more sustainable analytical procedures, innovative techniques are demanded. Given that, this work proposes a new integrative system (2D PLE × HPLC-PDA) and presents its validation for bioactive compound extraction and online quantification, discussing the main advantages and cares that need to be taken. Two food byproducts – passion fruit bagasse and coffee husks – were chosen as solid model samples. The system was configured to perform pressurized liquid extraction (PLE) with periodical automated extract injection in the HPLC, consequently obtaining the online quantification of target compounds from the solid samples. In parallel with the online injections, extract fractions were collected and submitted to offline analysis in which the extraction yield of piceatannol and chlorogenic acid and caffeine were evaluated, respectively, for passion fruit bagasse and coffee husks. The extraction yields obtained by online and offline injections were compared and were significantly equal (p > 0.05). Thus, the 2D PLE × HPLC-PDA system represents a feasible tool to integrate solid sample preparation and chemical analysis of biocompounds in a single and online step.

Evaluasi Konstanta Kecepatan Ekstraksi Beta (ß)-Karoten Berbasis Campuran Pelarut Aseton dan Dietil Eter

Research on the extraction of ß-carotene has been carried out intensively in recent years, considering the wide application of ß-carotene compounds, especially in the pharmaceutical and health fields. In the health sector, β-carotene has antioxidant compounds that can neutralize unstable molecules called free radicals. When the number of free radicals is too high in the body, it can cause cell and tissue damage which is known as oxidative stress. So the consumption of β-carotene should be increased. Various technologies are used for the isolation of ß-carotene from raw materials, such as maceration, soxhlet, ultrasound-assisted extraction (UAE), pressurized liquid extraction (PLE) and supercritical liquid extraction (SFE). This study uses the maceration method with the consideration that the energy used is relatively low and refers to the heat-resistant nature of β-carotene. The purpose of this study was to analyze the addition of co-solvent diethyl ether to acetone solvent to the value of the extraction rate constant (k). In this case, the addition of a co-solvent can help transport β-carotene to the solvent effectively by increasing the yield of β-carotene produced. Quantitative analysis was carried out using calculations based on mass balance, pseudo-second-order, and Peleg to then conclude which model is by the resulting data. The final yield of β-carotene was 34.395; 103.287 and 108.974 µg/g for diethyl ether, acetone, and a mixture of acetone with diethyl ether (24: 1) v/v respectively. The value of the extraction speed constant for each solvent diethyl ether, acetone, and a mixture of acetone with diethyl ether was 0.8913; 1.03975, and 2.0975 (minute-1) based on the Peleg model and 0.00738 for each solvent; 0.00828; 0.0141 (gram/mg.minute) based on the pseudo second-order model.

New Trends in Supercritical Fluid Technology and Pressurized Liquids for the Extraction and Recovery of Bioactive Compounds from Agro-Industrial and Marine Food Waste.

Growing consumer interest in healthy foods has led to an increased demand for bioactive compounds derived from eco-technologies. This review highlighted two emerging technologies, pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE), which are based on clean processes aimed at recovering bioactive compounds from different food sources. We studied how the different processing conditions provide many advantages and a great opportunity to obtain compounds with antioxidant, antibacterial, antiviral, or antifungal activity from plant matrices and industrial biowaste, especially antioxidant compounds (anthocyanins and polyphenols) due to their important role in health promotion. Our research was conducted through a systematic search in different scientific databases related to the PLE and SFE topics. The review analyzed the optimal extraction conditions using these technologies, which lead to the efficient extraction of bioactive compounds, the use of different equipment, and recent combinations of SFE and PLE with other emerging technologies. This has given rise to the development of new technological innovations, new commercial applications, and the detailed recovery of various bioactive compounds extracted from different plant and marine life food matrices. These two environmentally friendly methodologies are fully valid and have great future application prospects in biowaste valorization. They represent a feasible technological tool that can promote the implementation of a circular economy model for the food industry. The underlying mechanisms of these techniques were discussed in detail and supported by current literature.

Pressurized Liquid Extraction for the Recovery of Carotenoids and Functional Compounds from Green and Orange Dunaliella salina Biomasses

In recent years, intensive research has been conducted on natural carotenoids extraction using several processes. Conventional extraction methods require high amounts of solvents and a long extraction time. However, pressurized liquid extraction demonstrated to be an interesting method. The extraction efficiencies of pressurized liquid for the recovery of carotenoids, from the green and the orange biomasses of the microalga Dunaliella salina DunaDZ1, are described. Organic solvents were tested including ethanol, n-hexane, ethyl acetate and a mixture of n-hexane:ethanol (3:4). Moreover, three extraction temperatures were used (90, 120 and 150 °C) at constant pressure. Extraction efficiency and extracts characterization were conducted. Results have shown that temperature has a positive effect on extraction yield. HPLC characterization showed that β-carotene is the main carotenoid in the orange biomass, and lutein in the green biomass, with the presence of other minor carotenoids in both biomasses. The highest carotenoid amounts were found in the n-hexane orange biomass extract, with β-carotene isomers as the main carotenoid (138.54 and 357.10 mg/g of dry extract, for cis and trans isomers, respectively). Otherwise, extracts obtained at the lowest tested temperature provided the best carotenoid yields. The best results for the antioxidant activity were obtained at 120 °C for orange biomass ethyl acetate extract.

Development of a Pressurized Green Liquid Extraction Procedure to Recover Antioxidant Bioactive Compounds from Strawberry Tree Fruit (Arbutus unedo L.).

Strawberry tree fruits (Arbutus unedo L.) are a natural source of valuable biologically active compounds. Therefore, the aim of this work was to develop a green extraction approach using pressurized liquid extraction (PLE) to provide the highest yield of bioactive compounds. Different extraction solvents (distilled water, 50% and 96% ethanol) and different PLE parameters were investigated: temperature (40, 80, and 120 °C), static extraction time (5 and 10 min), and number of cycles (1 and 2). Total phenolic contents (TPC), hydroxycinnamic acids (HCA), flavonols (FL), total flavonoids (TF), condensed tannins (CT), and antioxidant capacity (DPPH and FRAP) were determined in PLE extracts. Solvent type, temperature, static extraction time, and number of cycles had a statistically significant effect on all bioactive compounds and antioxidant capacity (p ≤ 0.05). All bioactive compounds were positively correlated with temperature, except for TPC and DPPH. For all polyphenols studied, the optimal PLE parameters were a temperature of 120 °C, a static extraction time of 10 min and 2 cycles. The best solvent for most bioactive compounds was 96% ethanol, except for TPC, for which 50% ethanol was better. This study suggests that PLE is a promising tool to intensify the extraction of bioactive compounds from strawberry tree fruits.

Pressurized Liquid Extraction: A Powerful Tool to Implement Extraction and Purification of Food Contaminants.

Pressurized liquid extraction (PLE) is considered an advanced extraction technique developed in the mid-1990s with the aim of saving time and reducing solvent with respect to traditional extraction processes. It is commonly used with solid and semi-solid samples and employs solvent extraction at elevated temperatures and pressures, always below the respective critical points, to maintain the solvent in a liquid state throughout the extraction procedure. The use of these particular pressure and temperature conditions changes the physicochemical properties of the extraction solvent, allowing easier and deeper penetration into the matrix to be extracted. Furthermore, the possibility to combine the extraction and clean-up steps by including a layer of an adsorbent retaining interfering compounds directly in the PLE extraction cells makes this technique extremely versatile and selective. After providing a background on the PLE technique and parameters to be optimized, the present review focuses on recent applications (published in the past 10 years) in the field of food contaminants. In particular, applications related to the extraction of environmental and processing contaminants, pesticides, residues of veterinary drugs, mycotoxins, parabens, ethyl carbamate, and fatty acid esters of 3-monochloro-1,2-propanediol and 2-monochloro-1,3-propanediol from different food matrices were considered.