•A pressurized liquid extraction method was optimized and applied to the extraction of phenolic compounds of 11 baby-leaf samples.•An HPLC-DAD–MS method was developed to identify and quantify ...different phenolic compounds.•Comparison of the levels of phenolic compounds was made between the beginning and end of storage, showing small difference between sampling days.•Flavonols were the most stable compounds during refrigerated storage.
Ready-to-eat baby-leaf vegetables market has been growing and offering to consumers convenient, healthy and appealing products, which may contain interesting bioactive compounds. In this work, the composition and the evolution of the phenolic compounds from different baby-leaf vegetables during refrigerated storage was studied. The phenolic compounds were extracted using pressurized liquid extraction (PLE) and the phenolic profile of each sample was analyzed and quantified by using LC–MS and LC–DAD methods, respectively, at the beginning and at the end of a 10-day storage period. The baby-leaf vegetables studied included green lettuce, ruby red lettuce, swiss chard, spinach, pea shoots, watercress, garden cress, mizuna, red mustard, wild rocket and spearmint samples and a total of 203 phenolic compounds were tentatively identified and quantified. The main naturally phenolic compounds identified correspond to glycosylated flavonoids, with exception of green lettuce and spearmint leaves which had a higher content of hydroxycinnamic acids. Quantification of the main compounds showed a 10-fold higher content of total phenolic content of ruby red lettuce (483mgg−1) in relation to the other samples, being the lowest values found in the garden cress (12.8mgg−1) and wild rocket leaves (8.1mgg−1). The total phenolic content only showed a significant change (p<0.05) after storage in the green lettuce (+17.5%), mizuna (+7.8%), red mustard (−23.7%) and spearmint (−13.8%) leaves. Within the different classes of phenolic compounds monitored, the flavonols showed more stable contents than the hydroxycinnamic and hydroxybenzoic acids, although the behavior of each compound varied strongly among samples.
Laurus nobilis L., known as laurel or bay leaf, is a Mediterranean plant which has been long known for exhibiting various health-beneficial effects that can largely be attributed to the polyphenolic ...content of the leaves. Pressurized liquid extraction (PLE) is a green extraction technique that enables the efficient isolation of polyphenols from different plant materials. Hence, the aim of this research was to determine optimal conditions for PLE (solvent, temperature, number of extraction cycles and static extraction time) of laurel leaf polyphenols and to assess the polyphenolic profile of the optimal extract by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) as well as to evaluate the antioxidant activity determined by FRAP, DPPH and ORAC assays. The optimal PLE conditions were 50% ethanol, 150 °C, one extraction cycle and 5 min static time. The polyphenolic extract obtained at optimal PLE conditions comprised 29 identified compounds, among which flavonols (rutin and quercetin-3-glucoside) were the most abundant. The results of antioxidant activity assays demonstrated that PLE is an efficient green technique for obtaining polyphenol-rich laurel leaf extracts with relatively high antioxidant activity.
A sensitive quantification method using pressurized liquid extraction (PLE) and solid phase extraction (SPE) coupled with ultra-high performance liquid chromatography-tandem mass spectrometry ...(UHPLC-MS/MS) was developed for determination of 19 anthelmintic drugs (ADs) belonging to seven structural groups (Benzimidazoles, Diphenylsulfides, Imidazothiazoles, Hexahydropyrazines, Macrocylic lactones, Salicylanilides, Tetrahydropyrimidines) in environmental water and sediment samples. Eleven SPE cartridges, sample pH, elution solvents were tested to determine the optimal conditions for extraction. Among these investigated SPE types, the best recoveries for 19 target ADs were obtained from Oasis HLB cartridge with 37–102%, 45–103%, 37–88%, 28–82% and 31–90% for spiked river water, tap water, rainwater, wastewater, and sediment respectively (with RSD < 15%), except for closantel. The 19 ADs were separated within 10 min by a BEH C18 column and monitored in both positive and negative ions modes with switching electrospray ionization source. The cross-talk interferences were solved by identification of secondary mass spectrum of substances through MRM-IDA-EPI scanning using Qtrap. These interference peaks could be efficiently eliminated by setting MRM segments or using Qtrap to obtain tertiary fragmented information. The developed methods were satisfactory in terms of linearity, accuracy, and precision, and used eight isotopically labeled compounds as internal standards to correct matrix effects. Method quantification limit (MQL) for 19 ADs was below 1.1 ng/L, 0.4 ng/L, 5.4 ng/L and 2.3 ng/g for river water, tap water, wastewater, and sediment, respectively. The validated method was successfully used to investigate the occurrence of anthelmintics in water and sediment samples from Chengdu, China. All ADs were detected in environment with the concentrations at ng/L level.
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•The pressurized liquid extraction (PLE) and solid phase extraction (SPE) method for anthelmintics was optimized.•19 anthelmintics were simultaneously detected by ultra-high performance liquid chromatography-tandem mass spectrometry.•This approach was used successfully to analyze ng/L levels of different classes of anthelmintics in environment.•The method was applied to analysis of river, tap, rain, waste water samples and sediment samples.•The cross-talk interferences were identified by Qtrap through MRM-IDA-EPI scanning.
•Bioactive carbohydrates have been successfully extracted from artichoke bracts.•Highest yields of inositols and inulin were obtained by MAE and PLE, respectively.•MAE allowed the extraction of ...carbohydrates using lower temperature and times than PLE.•S. cerevisiae treatment allowed the removal of interfering carbohydrates.•Both MAE and PLE are appropriate for extraction of bioactive carbohydrates from industrial by-products.
Microwave assisted extraction (MAE) and pressurized liquid extraction (PLE) methods using water as solvent have been optimized by means of a Box–Behnken and 32 composite experimental designs, respectively, for the effective extraction of bioactive carbohydrates (inositols and inulin) from artichoke (Cynara scolymus L.) external bracts. MAE at 60°C for 3min of 0.3g of sample allowed the extraction of slightly higher concentrations of inositol than PLE at 75°C for 26.7min (11.6mg/g dry sample vs. 7.6mg/g dry sample). On the contrary, under these conditions, higher concentrations of inulin were extracted with the latter technique (185.4mg/g vs. 96.4mg/g dry sample), considering two successive extraction cycles for both techniques. Both methodologies can be considered appropriate for the simultaneous extraction of these bioactive carbohydrates from this particular industrial by-product. To the best of our knowledge this is the first time that these techniques are applied for this purpose.
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•Green extraction methods are used to recover bioactive compounds from Guanxuma.•Integrated approach by combining methods to enhance the phenolics extraction.•Depressurization step, ...prior to pressurized liquid extraction, aid the phenolics recovery.•New phenolic compounds were firstly detected from Guanxuma extracts.
Integrated downstream processes, combining Supercritical Fluid Extraction (SFE) with Pressurized Liquid Extraction (PLE), were used to recover antioxidants from Sida rhombifolia leaves. The SFE depressurization step was evaluated to improve PLE efficiency in the recovery of phenolic compounds. Total phenolic content of the extracts was performed by Folin-Ciocalteu method, and in vitro antioxidant activity was obtained by DPPH and ABTS methods, while the cell wall disruption was observed by Scanning Electron Microscopy (SEM) analysis. The highest phenolic content (91 ± 0 mg GAE g−1) and antioxidant capacity by ABTS (4.3 ± 0.02 mmol TE g−1 extract) was obtained by PLE from the SFE residue after fast depressurization rate. LC-ESI-MS/MS analysis identified 31 phenolic compounds from the extracts, of which 21 were firstly reported for Sida rhombifolia. Isoquercitin was the major phenolic in the extracts. The process integration recovered different fractions from S. rhombifolia leaves, improving extraction yield and antioxidant potential.
Camu-camu, a typical Amazonian fruit, is known for the high vitamin C content of the peel and pulp. As vitamin C is widely used in the food, pharmaceutical, and cosmetics industries, it is of ...interest to study new sources, extraction techniques, and analytical methods for the identification and quantification of this compound. Here, evaluation was made of extraction and quantification methods, as well as the differences in vitamin C content according to the origin and part of the camu-camu fruit. The extraction techniques studied were pressurized liquid extraction (PLE), acid extraction, and maceration. The analytical methods evaluated were titrimetry and chromatography. Camu-camu samples were obtained from different regions, and the peel and pulp were studied separately. Acid extraction using sulfuric acid as solvent provided the highest vitamin C yields, while PLE, as a completely clean technique, proved to be a promising alternative for the recovery of ascorbic acid (L-AA). The application of an ultra-high performance liquid chromatography methodology (UHPLC-DAD) enabled the fast identification and quantification of L-AA and dehydroascorbic acid (DHAA), with high resolution, sensitivity, and specificity. The results obtained using the chromatographic and titration methods were not significantly different (p < 0.05), indicating that titrimetry is useful for routine analyses. L-AA and DHAA were found in the peel, but only L-AA was found in the pulp. The variation of vitamin C content among the lots could be explained by the edaphoclimatic conditions. The combination of a clean extraction technique and a fast analytical method is a promising approach for the determination of vitamin C in food products.
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•Adequacy of aqueous solutions for the extraction and stabilization of ascorbic acid.•The PLE, as totally green technique, proved be promising for extraction of ascorbic acid in camu-camu.•The chromatographic analysis method allowed the detection and quantification of ascorbic acid and dehydroascorbic acid.•The camu-camu pulps had the highest levels of vitamin C.
Land use affects many aspects of regional sustainable development, so insight into its influence is of great importance for the optimization of national space. The book mainly focuses on functional ...classification, spatial conflict detection, and spatial development pattern optimization based on productivity, sustainability, and livability perspectives, presenting a relevant opportunity for all scholars to share their knowledge from the multidisciplinary community across the world that includes landscape ecologists, social scientists, and geographers. The book is systematically organized into the optimization theory, methods, and practices for PLES (production–living–ecological space) around territorial spatial planning, with the overall planning of PLES as the goal and the promotion of ecological civilization construction as the starting point. Through this, the competition and synergistic interactions and positive feedback mechanisms between population, resources, ecology, environment, and economic and social development in the PLES system were revealed, and the nonlinear dynamic effects among subsystems and elements in the system identified. In addition, a series of optimization approaches for PLES is proposed.
Land space is the carrier of human production, living activities, and ecological civilization construction. How to promote the orderly, moderate, and sustainable development and utilization of land ...space is a scientific problem to be solved. As a key element in China’s spatial planning, the quantitative analysis of spatial pattern and functional zoning has become a focus of China’s current development. Based on the analysis of land space symbiosis development, this study takes Henan province as the case study; appropriate indicators were selected from the perspective of “production-living-ecological” functions (PLEFs) index that was developed including three subsystems of the production function, living function, and ecological function. The entropy weight method and geographic information system (GIS) spatial method were used to analyze the PLEF status and spatial pattern in Henan province. The PLEF score showed a certain geographical pattern, where in the southwestern areas of Henan province have higher PLEFs than that in the northeastern areas. The PLEFs have an obvious positive correlation in the spatial distribution by spatial correlation analysis. In addition, this study designs a three-dimensional magic cube evaluation model to analyze the symbiotic function type of land space. The results indicated that the PLEFs of Henan province were classified into 13 symbiotic function types of areas, which can better reflect the spatial differentiation characteristics. Moreover, we proposed paths to promote the development and management of each type function area.
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.
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