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1.
Open Life Sci ; 19(1): 20220879, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005739

RESUMO

The corrosion of metals poses a threat to the economy, the environment, and human health due to undesirable reactions and contaminated products. Corrosion inhibitors, including natural products, can play a key role in protecting metallic materials, especially under challenging conditions. In this study, the roots of the Inula viscosa plant were examined for their ability to act as corrosion inhibitors in a 1 M hydrochloric acid (HCl) solution. Different extracts of the plant were evaluated for their corrosion inhibition capacity in a 1 M HCl solution. The effectiveness of different plant extracts was assessed, including an aqueous extract, an ethanolic extract, and a combined water-ethanol extract. Compounds present in the roots of Inula viscosa were identified using high-performance liquid chromatography. The electrochemical properties of the extracts were studied using various techniques such as open circuit potential, electrochemical impedance spectroscopy, and potentiodynamic polarization. Additionally, surface analysis after immersion was performed using scanning electron microscopy. Electrochemical data revealed that Inula viscosa root (IVR) extracts acted as mixed-type corrosion inhibitors with pronounced cathodic characteristics. The inhibitory efficiency was closely related to the concentration of Inula viscosa (I. viscosa), showing a significant increase with higher concentrations. This resulted in a decrease in corrosion current and an increase in polarization resistance. Notably, inhibitory efficiency reached high levels, up to 97.7% in mixed extract which represents a mixture between water and ethanol. In our study, it was observed that the mixed extract (water + ethanol) allowed for a greater corrosion inhibition compared to the other solvents studied, 97.7%. Surface analyses confirmed the formation of an organic film layer on the steel surface, attributed to the bonding of functional groups and heteroatoms in I. viscosa components. Therefore, this study paves the way for the potential integration of I. viscosa as a promising corrosion inhibition material, offering durable protection against steel corrosion and opening avenues for various related applications.

2.
Bioresour Bioprocess ; 11(1): 58, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849710

RESUMO

The global scientific community is deeply concerned about the deterioration of water quality resulting from the release of industrial effluents. This issue is of utmost importance as it serves to safeguard the environment and combat water pollution. The objective of this work is to elaborate a biomaterial of vegetable origin, based on the twigs of Aleppo pine, and to use it as an abundant and less expensive material for the treatment of wastewater. For this reason, the twigs were treated physically to get the powder called biomaterial FPA (Aleppo pine fiber), which was characterized by physicochemical, and spectroscopic analyses namely scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The crystallinity index of FPA was evaluated by the peak height method. The findings indicate that the FPA powder has an acidic nature, exhibiting a porous structure that promotes the adsorption and binding of molecules. Additionally, it has a zero charge point of 5.8 and a specific surface area of 384 m2.g-1. It is primarily composed of hydroxyl, carboxyl, and amine functional groups, along with mineral compounds and organic compounds, including cellulose and other mineral elements such as Ca, Mg, Fe, Na, P, Al, K, Ni, and Mo. Combining these characteristics, FPA biomaterial has considerable potential for use as an effective adsorbent biomaterial for various wastewater pollutants. Its abundance and relatively low cost make it an attractive solution to the growing challenges of water pollution worldwide.

3.
ACS Omega ; 9(14): 16656-16664, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38617605

RESUMO

This study investigated the effects of varying water stress levels on Rosmarinus officinalis essential oils (EO). Three samples (S1, S2, and S3) were cultivated under different stress levels (40, 60, and 80%). Increased water stress led to changes in primary and secondary metabolites, EO contents, and physical properties. Antioxidant activity varied, with S2 exhibiting the highest IC50 value. In terms of antidiabetic activity, S2 showed robust α-amylase inhibition, while S3 displayed a commendable influence. For α-galactosidase inhibition, S3 had a moderate effect, and S2 stood out with increased efficacy. Gas chromatography-mass spectrometry analysis revealed stress-induced changes in major compounds. The study enhances the understanding of plant responses to water stress, with potential applications in antioxidant therapy and diabetes management. The findings emphasize the importance of sustainable water management for optimizing the EO quality in its various uses.

4.
ACS Omega ; 9(8): 9236-9246, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434823

RESUMO

Morocco is known for its high plant biodiversity, but many plants are poorly valorized. For this reason, this study aims to valorize the methanolic and aqueous extracts of Melitotus albus leaves by studying their antioxidant activity and toxicity. The extracts' antioxidant activity is assessed using the FRAP, DPPH, CAT, and ABTS methods. The chemical composition was determined using LC-MS analysis and evaluated using in silico studies. The results revealed that the total polyphenol content of the aqueous extract, 259.26 ± 7.79 (mg GAE/g), is higher than that of the methanolic extract, 131.41 ± 12.64 (mg GAE/g). The antioxidant activity by the methods of DPPH, ABTS, and phosphor molybdenum of aqueous extracts (0.087 ± 0.015, 0.014 ± 0.001 and 6.157 ± 1.050 mg eq vit C/g, respectively) is greater than that of methanolic extracts (0.107 ± 0.02, 0.167 ± 0.03, and 0.453 ± 0.014 mg eq vit C/g, respectively). The reducing power of iron (FRAP) shows that the methanolic extract has a greater reducing power than that of the aqueous extract with a low IC50 (0.011 ± 0.003 and 0.199 ± 0.016 mg/mL, respectively). The study of acute and subacute toxicity shows that the administration of the aqueous extract of M. albus at different doses increases the body weight of rats without modifying their general behavior. The M. albus extract had a 99.99% total phenolic content, as determined by LC-MS, consisting of 12 different components. The primary constituents of the extract are chlorogenic acid (43.68%), catechin/epicatechin (24.82%), quercetin-3-O-glucuronic acid (9.91%), naringin (7.64%), and p-hydroxybenzoic/salicylic acid (2.95%). The in-silico study showed that these compounds can passively permeate through the blood and have a beneficial effect on various organs of the body. Based on these results, M. albus can be used as a medicinal plant in phytotherapy, cosmetics, or as a dietary supplement. The bioactive compounds of these plants will require a lot of further effort in terms of isolation and characterization.

5.
Plants (Basel) ; 13(3)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38337918

RESUMO

Origanum grosii (L.) and Thymus pallidus (L.) are medicinal plants recognized for their uses in traditional medicine. In this context, the aim of this article is to highlight the results of a phytochemical analysis (HPLC), with particular emphasis on the antioxidant (DPPH, TAC, and FRAP), analgesic, anti-inflammatory, haemagglutinin-test-related, and hemolytic activities of the total extracts of these plants. Phytochemical analysis via HPLC revealed that licoflavone C (30%) is the main compound in Origanum grosii, while hesperidin (43%) is found in T. pallidus. Evaluation of the antioxidant capacity of Origanum grosii and Thymus pallidus using the DPPH, TAC, and FRAP methods revealed an IC50 of the order of 0.085 mg/mL and 0.146 mg/mL, an EC50 of the order of 0.167 mg/mL and 0.185 mg/mL, and a total antioxidant capacity of between 750 mg EQ/g and 900 mg EQ/g, respectively. Analgesic evaluations revealed writhes inhibition of the order of 97.83% for O. grosii and 90% for T. pallidus. In addition, both plant extracts showed limited hemolytic activity, not exceeding 30% at a concentration of 100 mg/mL. Evaluation of the anti-inflammatory potential showed edema inhibition of the order of 94% (800 mg/kg) for O. grosii and 86% (800 mg/kg) for T. pallidus. These results highlight the potential applications of these extracts in pharmacological research.

6.
ACS Omega ; 8(49): 46598-46607, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107916

RESUMO

A central position in Moroccan ethnobotany is held by the Mentha genus, serving as a vital reference for aromatic and medicinal plants within the Lamiaceae family. The profound importance of Mentha species in the daily lives of Moroccans is recognized, and the primary objective of this study is to assess the impact of rising temperatures and decreasing precipitation on the primary and secondary metabolites of Mentha pulegium under the following climatic conditions: sample 1, cultivated under standard temperature and precipitation conditions during the first year; sample 2, subjected to an 8 °C temperature increase and a 25% reduction in water supply; and sample 3, exposed to a 12 °C temperature rise and a 50% decrease in water availability. Phytochemical screening results reveal a progressive decline in primary metabolites from sample 1 to sample 3 due to the increase in temperature and decrease in precipitation. Conversely, a distinct trend is observed in secondary metabolites and the yield of essential oil, increasing from sample 1 to sample 2 as the temperature rises and precipitation decreases. Remarkably, in sample 3, the yield of essential oil decreases as climatic conditions further deteriorate. Additionally, GC analysis demonstrates that modifications in the chemical compositions of essential oils occur because of the disruption of climatic parameters, particularly in the major compounds. Similarly, changes in climatic parameters significantly influence antioxidant activity, with sample 2 exhibiting the highest activity, as reflected by an IC50 value (half-maximal inhibitory concentration) of 14,874.04 µg/mL, followed by the third sample at 8488.43 µg/mL, whereas the first sample exhibits the lowest activity at 4505.02 µg/mL. In summary, the complex relationship between climatic factors and the chemical composition of Mentha pulegium is highlighted by our experiment, emphasizing its implications for medicinal properties within an ecological context.

7.
Pharmaceuticals (Basel) ; 16(12)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38139775

RESUMO

In the present study, we used benzimidazolone as a starting material to efficiently synthesize several hybrid compounds of pyrazole benzimidazolone derivatives by the 1,3-dipolar cycloaddition reaction. These compounds were obtained in average yields and were characterized by NMR (1H and 13C) and HRMS analysis. The antioxidant activity of the synthesized compounds 5(a-c) and 6(a-c) was evaluated using in vitro reduction assays, including ferric reducing antioxidant power (FRAP) and total antioxidant capacity (TAC). The results indicated that products 5c, 6b, and 6c exhibit higher antioxidant activity compared to the reference compounds and showed a remarkable ability to effectively remove the radical at IC50 (14.00 ± 0.14, 12.47± 0.02, and 12.82 ± 0.10 µM, respectively) under the TAC assessment. Conversely, compound 6c showed excellent activity at IC50 (68.97 ± 0.26 µM) in the FRAP assay. We carried out molecular docking and dynamics simulations to investigate the binding mode and stability of 5c, 6b, and 6c in the active site of human Peroxiredoxin 5. An ADMET study was conducted to determine the drug properties of the synthesized compounds.

8.
Sci Rep ; 13(1): 20021, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37973884

RESUMO

The study aimed at investigating the phytochemical composition, antioxidant and antibacterial activities of essential oils (EOs) of Origanum grossii and Thymus pallidus. The selection of these plants for the study was driven by a comprehensive survey conducted in the Ribat Elkheir region of Morocco, where these plants are widely utilized. The results reflect the valorization of these plants based on the findings of the regional survey. The GC-MS phytochemical analysis revealed that the main constituents of the essential oil were carvacrol and thymol for O. grossii and T. pallidus respectively. Quantitative assays demonstrated that O. grossii exhibited higher levels of polyphenols (0.136 mg AGE/mg EO) and flavonoids (0.207 mg QE/mg EO) compared to T. pallidus. The DPPH assay indicated that O. grossii EOs possessed approximately twice the antiradical activity of T. pallidus, with IC50 values of approximately 0.073 mg/mL and 0.131 mg/mL, respectively. The antibacterial activity tests showed that both essential oils exhibited significant inhibition zones ranging from 26 to 42 mm against all tested bacterial strains. The MIC values varied among the bacteria, generally falling within the range of 0.31 to 2.44 µg/mL, demonstrating the potency of the EOs to serve as antibacterial. Molecular docking revealed that O. grossii and T. pallidus essential oils interact with antibacterial and antioxidant proteins (1AJ6 and 6QME). Key compounds in O. grossii include p-cymene, eucalyptol, and carvacrol, while T. pallidus contains potent chemicals like p-cymene, ɤ-maaliene, valencene, α-terpinene, caryophyllene, himachalene, and thymol. Notably, the most potent chemicals in Origanum grossii are p-cymene, eucalyptol, and carvacrol, while the most potent chemicals in Thymus pallidus are p-cymene, α-terpinene, and thymol. These findings suggest that these plant EOs could be used to develop new natural products with antibacterial and antioxidant activity.


Assuntos
Óleos Voláteis , Origanum , Thymus (Planta) , Óleos Voláteis/química , Timol/química , Origanum/química , Eucaliptol , Antioxidantes/farmacologia , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Antibacterianos/química , Compostos Fitoquímicos/farmacologia , Thymus (Planta)/química
9.
Molecules ; 28(14)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37513216

RESUMO

The synthesis of 5,6,7,8-tetrahydro-[1,2,4]triazolo[5,1-b]quinazolin-9(4H)-one (THTQ), a potentially biologically active compound, was pursued, and its structure was determined through a sequence of spectral analysis, including 1H-NMR, 13C-NMR, IR, and HRMS. Four bacterial and four fungal strains were evaluated for their susceptibility to the antibacterial and antifungal properties of the THTQ compound using the well diffusion method. The impact of THTQ on the corrosion of mild steel in a 1 M HCl solution was evaluated using various methods such as weight loss, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) analysis. The study revealed that the effectiveness of THTQ as an inhibitor increased with the concentration but decreased with temperature. The PDP analysis suggested that THTQ acted as a mixed-type inhibitor, whereas the EIS data showed that it created a protective layer on the steel surface. This protective layer occurs due to the adsorption behavior of THTQ following Langmuir's adsorption isotherm. The inhibition potential of THTQ is also predicted theoretically using DFT at B3LYP and Monte Carlo simulation.


Assuntos
Antifúngicos , Quinazolinonas , Antifúngicos/farmacologia , Quinazolinonas/farmacologia , Temperatura , Aço/química , Antibacterianos/farmacologia
10.
IUCrdata ; 8(Pt 5): x230409, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37287860

RESUMO

The triazole ring in the title mol-ecule, C9H10N4O, is not quite coplanar with the six-membered ring to which it is fused, the dihedral angle between the two least-squares planes being 2.52 (6)°. In the crystal, a layered structure is formed by N-H⋯N and C-H⋯O hydrogen bonds plus slipped π-stacking inter-actions, with the fused cyclo-hexene rings projecting to either side.

11.
Foods ; 12(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37297464

RESUMO

Canola, Brassica napus L., is a major oilseed crop that has various uses in the food, feed, and industrial sectors. It is one of the most widely produced and consumed oilseeds in the world because of its high oil content and favorable fatty acid composition. Canola grains and their derived products, such as canola oil, meal, flour, and bakery products, have a high potential for food applications as they offer various nutritional and functional benefits. However, they are affected by various factors during the production cycle, post-harvest processing, and storage. These factors may compromise their quality and quantity by affecting their chemical composition, physical properties, functional characteristics, and sensory attributes. Therefore, it is important to optimize the production and processing methods of canola grains and their derived products to ensure their safety, stability, and suitability for different food applications. This literature review provides a comprehensive overview of how these factors affect the quality of canola grains and their derived products. The review also suggests future research needs and challenges for enhancing canola quality and its utilization in food.

12.
Int J Biol Macromol ; 239: 124328, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37019199

RESUMO

Contamination in water is due to various environmental pollutants from natural and anthropogen activities. To remove toxic metals from contaminated water, we developed a novel adsorbent in foam form based on an olive industry waste material. The foam synthesis involved oxidation of cellulose extracted from the waste to dialdehyde, functionalization of the cellulose dialdehyde with an amino acid group, reacting the functionalized cellulose with hexamethylene diisocyanate and p-phenylene diisocyanate to produce the target polyurethanes Cell-F-HMDIC and Cell-F-PDIC, respectively. The optimum condition for lead(II) adsorption by Cell-F-HMDIC and Cell-F-PDIC were determined. The foams show the ability to quantitatively remove most of metal ions present in a real sample of sewage. The kinetic and thermodynamic studies confirmed a spontaneous metal ion binding to the foams with a second pseudo-order adsorption rate. The adsorption study revealed it obeys the Langmuir isotherm model. The experimental Qe values of both foams Cell-F-PDIC and Cell-F-HMDIC were 2.1929 and 2.0345 mg/g, respectively. Monte Carlo (MC) and Dynamic (MD) and simulations showed excellent affinity of both foams for lead ions with high adsorption negative energy value indicating vigorous interactions of Pb(II) with the adsorbent surface. The results indicate the usefulness of the developed foam in commercial applications. ENVIRONMENTAL IMPLICATION: Elimination of metal ions from contaminated environments is important for a number of reasons. They are toxic to humans via interaction with biomolecules, resulting in disruption of the metabolism and biological activities of many proteins. They are toxic to plants. Industrial effluents and/or wastewater discharged from production processes, contain a considerable amount of metal ions. In this work, the use of naturally produced materials, such as olive waste biomass, as adsorbents for environmental remediation has received great attention. This biomass represents unused resources and presents serious disposal problems. We demonstrated that such materials are capable of selectively adsorbing metal ions.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Purificação da Água , Humanos , Celulose/química , Poliuretanos , Aminoácidos , Metais , Purificação da Água/métodos , Íons , Água , Adsorção , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
13.
ACS Omega ; 7(37): 32949-32958, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36157745

RESUMO

A novel double-open-cubane (NNCO)6Co4Cl2 cluster with a Co4O6 core was made available under aqua-ultrasonic open atmosphere conditions for the first time. The ultrasonic clusterization of the (3,5-dimethyl-1H-pyrazol-1-yl)methanol (NNCOH) ligand with CoCl2·6H2O salts in ethanol yielded a high-purity and high-yield cluster product. Energy-dispersive X-ray (EDX), Fourier transform infrared (FT-IR), and ultraviolet (UV)-visible techniques were used to elucidate the clusterization process. The double-open-Co4O6 cubane structure of the (NNCO)6Co4Cl2 cluster was solved by synchrotron single-crystal X-ray diffraction (SXRD) and supported by density functional theory (DFT) optimization and thermogravimetric/differential TG (TG/DTG) measurements; moreover, the DFT structural parameters correlated with the ones determined by SXRD. Molecular electrostatic potential (MEP), Mulliken atomic charge/natural population analysis (MAC/NPA), highest occupied molecular orbital/lowest unoccupied molecular orbital (HOMO/LUMO), density of states (DOS), and GRD quantum analyses were computed at the DFT/B3LYP/6-311G(d,p) theory level. The thermal behavior of the cluster was characterized to support the formation of the Co4O6 core as a stable final product. The catalytic property of the (NNCO)6Co4Cl2 cluster was predestined for the oxidation process of 3,5-DTBC diol (3,5-di-tert-butylbenzene-1,2-diol) to 3,5-DTBQ dione (3,5-di-tert-butylcyclohexa-3,5-diene-1,2-dione).

14.
Environ Sci Pollut Res Int ; 29(1): 133-145, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34031820

RESUMO

An ethnobotanical survey was conducted among herbalists in the north-central region of Morocco using a questionnaire in order to highlight knowledge and know-how and to establish an inventory of herbal remedies used in the treatment of diseases common in the region and rarely cited in the bibliography: in this case, it is insomnia, asthenia, and oral-gum infections. The results showed that 120 herbalists were interviewed in different areas of the Fez-Meknes region, about 86 species were cited and grouped into 60 families (47 plants to treat asthenia, 25 to treat insomnia, and 21 to treat oral and gum infections). The reported plants have been identified and presented with the binomial name, family, part used, and method of preparation. In addition, the versatility was observed in several plants, indicating that the same plant could be used to treat conditions of different groups. Herbalists are people of both sexes belonging to different age groups and have different socioeconomic and intellectual levels. Eighty percent of surveyed herbalists are willing to provide us information about plants in the studied area. The most cited plants for treating these diseases are Lavandula dentata, Matricaria chamomilla, Rosmarinus officinalis, Allium cepa, Origanum vulgare, Origanum majorana, Marrubium vulgare, Lepidium sativum, and Ocimum basilicum. The Lamiaceae are the most quoted family. The leaves are the most commonly used organs. Infusion is the most common form of preparation. The results of this ethnobotanical study could constitute an important source of information and databases for further research in the fields of phytochemistry and pharmacology in order to find new bioactive molecules. In addition, this document can be used in the protection of indigenous knowledge.


Assuntos
Astenia/tratamento farmacológico , Doenças da Boca/tratamento farmacológico , Fitoterapia , Plantas Medicinais , Distúrbios do Início e da Manutenção do Sono , Etnobotânica , Humanos , Medicina Tradicional , Marrocos , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Inquéritos e Questionários
15.
Environ Sci Pollut Res Int ; 29(1): 146-157, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34409534

RESUMO

This work concerns the reuse of treated wastewater from Er-Rachidia wastewater treatment plant (WWTP) in the mixing of ordinary C20/25 concrete, to reduce the overexploitation of non-potable groundwater, avoid its discharge into watercourses and reduce the risk of environmental pollution due to its mineral and organic matter load. In this respect, three types of mixing water were used in this study: drinking water (DW), non-potable groundwater (GW), and treated wastewater (TW). The results recorded for each type of mixing water, in the fresh and hardened state of concretes, were compared with the requirements of the standards. The obtained results show that the treated wastewater does not have any adverse effect upon the quality of the concrete; it has shown an improvement of the mechanical strength from the first stage, a similar density, setting time, and porosity and a slight decrease of the workability compared with the control concrete. A one-way analysis of variance (ANOVA) of the mechanical performance of concrete at different cure times (7, 14, 28, and 90 days) has shown that there is no significant decrease in the mechanical performance of concretes based on TW and GW compared with concretes formulated with DW. Through this study, the substitution of drinking water by treated TW and GW will help to minimize the footprint of construction materials on natural resources. From a point of view of the mechanical performance, TW and GW improve the mechanical performance of concrete. Additionally, it makes wastewater treatment plants more economically attractive and contributes to sustainable development.


Assuntos
Água Potável , Água Subterrânea , Purificação da Água , Materiais de Construção , Águas Residuárias
16.
Heliyon ; 6(10): e05067, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33072903

RESUMO

Statistical modeling of the corrosion inhibition process by twenty-one pyridazine derivatives for mild steel in acidic medium was investigated by the quantitative structure property relationship (QSPR) approach. This modeling was established by the correlation between the corrosion inhibition efficiency (IE %) and a number of the electronic and structural properties of these inhibitors such as: the E HOMO (highest occupied molecular orbital energy), the E LUMO (lowest unoccupied molecular orbital energy), the energy gap (E L-H ), the dipole moment (µ), the hardness (η), the softness (σ), the absolute electronegativity (χ), the ionization potential (IP), the electron affinity (EA), the fraction of electrons transferred (ΔN), the electrophilicity index ω the molecular volume (V m ), the logarithm of the partition coefficient (Log P), and the molecular mass (M), in addition to the inhibitor concentration (C i ). The structure electronic properties was calculated by the use of the density functional theory method (DFT), at B3LYP/6-31G (d, p) level of theory and the analysis of dimensionality and redundancy as well as the test of collinearity between descriptors are carried out using principal component analysis (PCA). Whereas, the correlation between EI % and molecular structure is performed through the development of tree mathematical models, based-QSPR approaches: the partial least squares regression (PLS), the principal component regression (PCR) and the artificial neural networks (ANN). Indeed, the statistical quantitative results revealed that PCR and ANN were the most relevant and predictive models in comparison with the PLS model. This pertinence was demonstrated by using leave one-out cross-validation as an efficient method for testing the internal stability and predictive capability of said models with a high cross-validated determination coefficient R 2 cv = 0.92 and predicted determination coefficient R 2 pred = 0.92 and R 2 pred = 0.90 for PCR and ANN respectively; in addition to an extrapolation test set as an external validation with a significant external coefficient of determination: R 2 test = 0.94 and R 2 test = 0.92, for the two correspondingly models.

17.
ScientificWorldJournal ; 2019: 3659432, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057339

RESUMO

The extraction of essential oils is generally carried out by two main techniques: azeotropic distillation (hydrodistillation, hydrodiffusion, and steam distillation) and extraction with solvents. However, these traditional methods are a bit expensive, especially since they are extremely energy and solvent consuming. This work consists in studying two methods of extraction of the essential oils of Rosmarinus officinalis L.: microwave assisted hydrodistillation (MAH) and Clevenger hydrodistillation (CH). Several parameters have been studied: the extraction time, the yield, and the chemical composition of the essential oils as well as the efficiency and cost of each procedure. The results obtained revealed that microwave-assisted hydrodistillation makes it possible to minimize the extraction time of the essential oils in comparison with conventional hydrodistillation. Thus, the same yield of essential oils is obtained for 20 minutes only with MAH while it takes 180 minutes with CH. In addition, the quality of the essential oil is improved thanks to a 1.14% increase in oxygenates. In conclusion, the MAH method offers significant advantages over conventional hydrodistillation and can therefore replace it on a pilot and industrial scale.

18.
Artigo em Inglês | MEDLINE | ID: mdl-24427091

RESUMO

In the title compound, C5H7N5S·H2O, the main mol-ecule is approximately planar, with a maximum deviation from the mean plane through the non-H atoms of 0.1478 (12) Šfor the amine N atom. In the crystal, the components are connected via N-H⋯O, N-H⋯S and O-H⋯N hydrogen bonds, forming a three-dimensional network.

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