In this contribution, the capabilities of pressurized liquid extraction (PLE) using food-grade solvents, such as water and ethanol, to obtain antioxidant extracts rich on polyphenolic compounds from ...olive leaves are studied. Different extraction conditions were tested, and the PLE obtained extracts were characterized
in vitro according to their antioxidant capacity (using the DPPH radical scavenging and the TEAC assays) and total phenols amounts. The most active extracts were obtained with hot pressurized water at 200
°C (EC
50 18.6
μg/mL) and liquid ethanol at 150
°C (EC
50 27.4
μg/mL), attaining at these conditions high extraction yields, around 40 and 30%, respectively. The particular phenolic composition of the obtained extracts was characterized by LC–ESI-MS. Using this method, 25 different phenolic compounds could be tentatively identified, including phenolic acids, secoiridoids, hydroxycinnamic acid derivatives, flavonols and flavones. Among them, hydroxytyrosol, oleuropein and luteolin-glucoside were the main phenolic antioxidants and were quantified on the extracts together with other minor constituents, by means of a UPLC–MS/MS method. Results showed that using water as extracting agent, the amount of phenolic compounds increased with the extraction temperature, being hydroxytyrosol the main phenolic component on the water PLE olive leaves extracts, reaching up to 8.542
mg/g dried extract. On the other hand, oleuropein was the main component on the extracts obtained with ethanol (6.156–2.819
mg/g extract). Results described in this work demonstrate the good possibilities of using PLE as a useful technique for the valorization of by-products from the olive oil industry, such as olive leaves.
Chia seeds constitute a promising source of α-linolenic acid (ALA). In the present work, an underutilized and cheaper set of chia seeds, which were discarded after the harvest according to quality ...criteria - named in this work as low oil content seeds (LOCS) - have been evaluated as a potential source for obtaining PUFA-enriched oils against the commonly studied high-quality chia seeds denoted as high oil content seeds (HOCS) in this study. Two efficient and environmental friendly techniques, supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE), were evaluated to optimize the extraction process of chia oil. At 60 °C, by using pressurized food-grade ethanol, recoveries close to 100% were achieved from both sets of seeds in a short extraction time (10 min). By using SFE, the greatest oil extraction yield (>95%) was attained at the highest pressure and temperature conditions (45 MPa and 60 °C) after 240 min. At the early stage of SFE extraction, both LOCS and HOCS exhibited a similar kinetic behavior, reaching oil extraction rates of 0.59 g oil/min and 0.64 g oil/min, respectively. No differences were found between the fatty acid profile of the oils extracted from LOCS and HOCS both by PLE and SFE. ALA and linoleic acid (LA) concentrations ranged between 65‐68% and 17–23% respectively, and a predominance of high molecular weight triglycerides (≥ CN50), was found in all extracted oils. In conclusion, LOCS might constitute a new suitable raw material for the production of ALA-enriched oils. Concerning the extraction methods assayed, the oil was almost entirely recovered by both PLE and SFE at the used conditions.
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•The economical, underutilized chia seeds were studied to obtain omega-3 rich oils.•Two green techniques were applied, supercritical fluid and pressurized liquid extraction.•The fatty acid composition obtained from high and low oil content seeds were very similar.•High oil recoveries were obtained from both types of seeds.•Low oil content seeds are a relevant alternative to obtain α-linolenic acid enriched oils.
•Thymus munbyanus subsp. coloratus and munbyanus were studied.•Essential oils, pressurized liquid and supercritical fluid extracts were obtained.•Extracts were examined for total phenolic and ...antioxidant activities.•Pressurized liquid extracts had the strongest antioxidant capacity.
The aim of this study was to demonstrate the potential of extracts from Algerian Thymus munbyanus as a valuable source of antioxidants for use on an industrial level. To this end, a study was conducted on the composition and antioxidant activities of essential oils (EOs), pressurized liquid extracts (PLE) and supercritical fluid extracts (SFE-CO2) obtained from Thymus munbyanus subsp. coloratus (TMC) and subsp. munbyanus (TMM). EOs and SFE-CO2 extracts were analysed by GC-FID and GC×GC-TOFMS revealing significant differences. A successive extraction of the solid SFE-CO2 residue by PLE extraction with solvents of increasing polarity such as acetone, ethanol and water, was carried out. The extracts were evaluated for total phenolic content by Folin–Ciocalteu assay, while the antioxidant power was assessed by DPPH, FRAP, and ORAC assays. SFE-CO2 extracts were also analysed for their tocopherol content. The antioxidant activity of PLE extracts was found to be higher than that of SFE-CO2 extracts, and this increased with solvent polarity (water > ethanol > acetone). Overall, these results support the use of T. munbyanus as a valuable source of substances to be used on an industrial level as preservative agents.
The acquisition of new mobile genetic elements contributes to the genetic diversity of
Vibrio cholerae
strains. An important role in this process belongs to the genetic material obtained from phages.
...The aim
of this work was to identify phage-induced PLE islands in strains of
V. cholerae
O1 serogroup and to determine the resistance of isolates with and without those mobile genetic elements to the lytic activity of the diagnostic cholera El Tor bacteriophage.
Materials and methods
. Whole genomes nucleotide sequences of toxigenic and non-toxigenic
V. cholerae
O1 strains presented in the NCBI GenBank were used for the work. Bioinformatic analysis was performed using the BLAST algorithm, MEGA X (or BioEdit v. 7.0.9.0). The test with phages was carried out according A. Gratia technique.
Results and discussion
. The analysis of 39 toxigenic strains imported to the territory of the Russian Federation and neighboring countries has revealed one strain of
V. cholerae
O1 of the classical biovar containing the PLE5 island, and 13 strains of
V. cholerae
O1 of the El Tor biovar containing the PLE4 island. PLE islands have not been found in non-toxigenic strains. It is shown that strains with PLE4 belong to
V. cholerae
O1 genovariants of the El Tor biovar and have the
ctxB1
gene allele. Isolates with this mobile element caused sporadic cases of the disease in 1994–1999, as well as cholera outbreaks in the Russian Federation (in 1993–1994, in 1998 – Dagestan, and 1993 – Tatarstan) and Ukraine (1994–1995). It has been suggested that, perhaps, the presence of the PLE4 island makes a certain contribution to the resistance of
V. cholerae
O1 strains of the El Tor biovar to the diagnostic cholera El Tor phage (55.6 % of phage-resistant isolates were detected), but there are other mechanisms that have not yet been identified. Thus, the data on the presence of new mobile genetic elements in the genome of earlier imported toxigenic strains of
V. cholerae
O1, biovar El Tor have been obtained, which expands information about their genetic organization.
Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous disease characterized by persistent airflow limitation but still lacking effective treatments.
Britt.
an important ...traditional medicinal plant with excellent antioxidant and anti-inflammatory properties, is widely used for the treatment of respiratory disease in China. However, its protective activity and mechanism against COPD airway inflammation have not been fully studied. Here, the anti-inflammatory effects of the PLE were investigated, and its underlying mechanisms were then elucidated. The presented results suggested a notable effect of the PLE on airway inflammation of COPD, by significantly ameliorating inflammatory cell infiltration in lung tissue, lessening leukocytes (lymphocytes, neutrophils, and macrophages) and inflammatory mediators (interleukin 4 (IL-4), IL-6, IL-17A, interferon γ (IFN-γ), and tumor necrosis factor α (TNF-α)) in the bronchoalveolar lavage fluid (BALF) of cigarette smoke (CS)/lipopolysaccharide (LPS)-induced COPD mice
and inhibiting the production of inflammatory factors (nitric oxide (NO), IL-6, and TNF-α) and intracellular reactive oxygen species (ROS) in LPS-stimulated RAW264.7 cells
. For further extent, PLE treatment significantly suppressed the expression and phosphorylation of TLR4, Syk, PKC, and NF-κB p65
and their mRNA
Subsequently, by co-treating with their inhibitors
, its potential mechanism
TLR4/Syk/PKC/NF-κB p65 signals was disclosed. In summary, the obtained results indicated a noteworthy effective activity of the PLE on COPD inflammation, and partly, the TLR4/Syk/PKC/NF-κB p65 axis might be the potential mechanism.
Due to their widespread use in human and animal healthcare, antibiotics and other drug residues are ubiquitous in the aquatic environment. Given their potential impacts on ecosystem functioning and ...public health, the quantification of environmental drug residues has become a necessity. Various analysis techniques have been found to be suitable for reliable detection of such compounds. However, quantification can be difficult because these compounds are present at trace or ultra-trace levels. Consequently, the accuracy of environmental analyses depends on both the efficiency and the robustness of the extraction and quantification method. In this work, an off-line solid-phase extraction (SPE) combined with on-line SPE-LC-MS/MS was applied to the simultaneous extraction and quantification of 26 pharmaceutical products, including 18 antibiotics, dissolved in a water phase. Optimal conditions were determined and then applied to assess the contamination level of the targeted drug residues in water collected from four sites in Northern France: a river, the input and output of an aerated lagoon, and a wastewater treatment plant. Drug residues associated with suspended solid matter (SSM) were also quantified in this work using pressurized liquid extraction (PLE) combined with an on-line SPE-LC-MS/MS system in order to complete an assessment of the degree of total background pollution.
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•High level of drug residues in treated and untreated wastewater in worldwide scale•Simultaneous analysis of 26 drug residues by an off-line and on-line SPE-LC-MS/MS•pH can influence on the analysis of drugs when using SPE-LC-MS/MS.•Low eliminations of antibiotics were determined in WWTP and aerated lagoon.•Natural water was contaminated by various drugs including antibiotics.
Lymphatic abnormalities in patients with single ventricle physiology can lead to early Fontan failure and severe Fontan complications, such as protein-losing enteropathy (PLE), plastic bronchitis ...(PB), chylothorax, and edema. Recent developments in lymphatic imaging and interventions have shed new light on the lymphatic dysfunction in this patient population and the role of the lymphatic circulation in PLE, PB, and chylothorax. In this study, we reviewed some of the latest developments in this field and discuss new treatment options for these patients.
The concept of Personal Learning Environment (PLE) is considered as a possible lens to understand and analyse learning conditions in different educational contexts from an ecological perspective, ...connecting with student's agency in their learning. Previous literature shows partial approaches on how it is implemented in higher education practice and leaves a research gap regarding how it is promoted from the learning design considering student's agency. It is in this space that the present study is framed. Through a qualitative approach, semi-structured interviews have been conducted with 20 faculty members from 5 different countries, to find out about the educational tasks that promote PLE in their courses. A sample of 34 academic tasks has been analysed through a coding system based on the learning design, the parts of the PLE and the student agency involved. The results show that the implementation of tasks for the promotion of the PLE still has room for improvement, affecting aspects of assessment, promotion of metacognition and student self-direction. As conclusions, lines of work that can be considered in practice and research on PLE are provided.
El concepto de Entorno Personal de Aprendizaje (PLE) se considera como una posible lente para entender y analizar las condiciones de aprendizaje en diferentes contextos educativos desde una perspectiva ecológica, conectando con la agencia del estudiante en su aprendizaje. La literatura previa muestra enfoques parciales de cómo se implementa en la práctica educativa universitaria y deja un vacío de investigación respecto a cómo se promueve desde el diseño educativo considerando la agencia del estudiante. Es en este espacio en que se enmarca el presente estudio. A través de un enfoque cualitativo, se han realizado entrevistas semiestructuradas con 20 profesores universitarios de 5 países diferentes, para averiguar sobre las tareas educativas que promueven el PLE en sus asignaturas. Se ha analizado una muestra de 34 tareas académicas a través de un sistema de codificación basado en el diseño educativo, las partes del PLE y cómo aparece la agencia del estudiante. Los resultados muestran que la implementación de tareas para la promoción del PLE todavía tiene margen de mejora, incidiendo en aspectos de evaluación, promoción de la metacognición y la autodirección de los estudiantes. Como conclusiones, se aportan líneas de trabajo que puedan considerarse en la práctica y la investigación sobre PLE.
The aim of the study was to investigate both L2 word integration and the effect of learning method on it. For this purpose, an L2 word-learning paradigm was designed with two learning methods: L2 ...words were paired with videos in the first one and their translation-equivalent L1 words in the second. To test L2 word integration, a lexical decision task associated with form priming was administered before and after the learning phase. The L2 words to be learned were used as primes. Forty-eight participants participated in the study. Before learning, a facilitation effect was obtained with pseudowords (not already learned L2 words) as primes and L1 words as targets. After learning, L2 words no longer facilitated L1 word recognition when learned with the video method, while they still had this effect when learned with the L1 words – L2 words method. In accordance with the prime lexicality effect (PLE), this absence of a facilitation effect indicates that L1 words and L2 words are involved in a lexical competition process common to the two languages. This result highlights swift lexicalisation and demonstrates the effect of learning method in lexicalisation.
•Two learning methods of L2 words were compared: translation equivalent and video.•L2 word integration was investigated by form priming in a L1 lexical decision task.•Before learning, unknown L2 words used as prime facilitated L1 word recognition.•After learning, this effect vanished with the L2 words learned by the video method.•This result demonstrates the effect of learning method on L2 word integration.
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