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- Natural antioxidants in emulsions O/WPublication . EL-GEUNDOUZ, Soukaina; Azza, S.; Dandlen, Susana Anahi; MAJDOUB, Nesrine; Lyoussi, Badiaa; Raposo, Sara; Gomes, Vera; Bankova, Vassya; Popova, Milena; Antunes, Maria Dulce; Miguel, Maria GracaThis study compared the capacity of propolis extract (PE) and thyme waste extract (TWE) to prevent the oxidation of oil in water (O/W) emulsion, as well as their impact on emulsion apparent viscosity (AV) in the presence of wheat germ and almond oils as lipid phase. For this, central composite design (CCD) and principal component analysis (PCA) were performed. Oxidation process was monitored by evaluating the formation of primary and secondary lipid oxidation products, at the same time the AV behavior was determined evaluating consistency index and flow behavior index. The results revealed that the increase of PE% and TWE% decreases TBARS (Thiobarbituric Acid Reactive Substances) and hydroperoxides formation. Viscosity increases with the rise of TWE% over (0.04%), whereas lower concentrations of PE% decreases it. Those results have been confirmed in the PCA analysis. TWE showed higher resistance to oxidation, although PE was more effective as antioxidant than TWE.
- Response surface methodology (RSM) for optimization of Euphorbia resinifera and Euphorbia officinarum extracts with antioxidant and anti-diabetic activitiesPublication . Boutoub, Oumaima; AAZZA, Smail; EL-GUENDOUZ, Soukaina; El Ghadraoui, Lahsen; Miguel, MariaBackground: Euphorbia is one of the plants most used by herbalists and therapists in Morocco. Objectives: The aerial part of two plant samples (Euphorbia resinifera and Euphorbia officinarum) collected in Morocco was examined for the solvent effect, extraction time, and plant concentration in order to determine the best extraction conditions. Materials and Methods: To achieve this goal, a response surface methodology (RSM) using a full three-level factorial design was used to optimize the conditions for the extraction of antioxidants and a-glucosidase inhibitors. Temperature, time, and plant-to-solvent ratio (PSR) and their linear and quadratic interactions on TPC (total phenol concentration), TFC (total flavonoid concentration), DPPH (2,2-diphenyl-1-picrylhydrazyl) trapping activity, and a-glucosidase inhibiting activities were studied. Results: According to desirability functions, the optimum operating conditions to achieve a higher extraction yield of phenols and higher antioxidant and anti-diabetic activity were found by using extraction during 60 min at 30 degrees C using a PSR of 20 mg/mL, whereas a longer extraction time (270 min) was needed for E. resinifera and a higher extraction temperature (50 degrees C), with a lower PSR (10 mg/mL) for E. officinarum. Conclusion: In order to find the best conditions to extract secondary metabolites with biological activity and application in phytotherapy, the appropriate solvent generally used by populations, water in this case, should be used, but the best extraction conditions have to be found in order to enhance the pharmacological actions.
- Two extraction methods of essential oils: conventional and non-conventional hydrodistillationPublication . El Kharraf, Sara; Farah, Abdellah; G, Miguel; EL-GUENDOUZ, Soukaina; El Hadrami, El MestafaThe traditional extraction of essential oils exposes plant material to high temperatures for hours, which may lead to the production of artifacts, even originating unpleasant odors and loss of quality. In addition, this procedure is energy-consuming, which makes it an expensive method. The present work has been focused on a method that combines hydrodistillation and subsequent extraction with water vapor and volatiles of essential oil in the same apparatus, that we called non-conventional hydrodistillation (NCH). Three aromatic plants were used: Rosmarinus officinalis leaves (X-1), Lavandula angustifolia flowers (X-2), and Citrus aurantium leaves (X-3). In the processes, the operating parameters as vegetal mass moisture, total sum vegetal mass used, and water flux rate have been fixed at 17 %, 100 g, and 0.97 L/h, respectively. The extraction process was made using mixture experimental design, taking into account the plants used (one plant, binary and ternary combinations); the position of the plants in the apparatus to study essential oils' yields. The results showed that NCH of binary and ternary mixtures allows obtaining higher yields than expected with values superior to 2 % for the following combinations: X-1:X-2 (50:50), X-1:X-3 (50:50); X-1:X-2:X-3 (33:33:33) and X-1:X-2:X-3 (0.67: 0.16:0.16). The new NCH had a high kinetic coefficient k (2.98) and lower extraction time (70 min) than conventional hydrodistillation (CH), which means less energy consumption.
- Comparative study of the antioxidant and enzyme inhibitory activities of two types of Moroccan Euphorbia entire honey and their phenolic extractsPublication . Boutoub, Oumaima; EL-GUENDOUZ, Soukaina; Manhita, Ana; Dias, Cristina Barrocas; Estevinho, Letícia M.; Paula, Vanessa B.; Carlier, Jorge; Costa, Maria Clara; Rodrigues, Brígida; Raposo, Sara; Aazza, Smail; El Ghadraoui, Lahsen; Miguel, Maria GraçaHoney is a natural food product very famous for its health benefits for being an important source of antioxidant and phenolic compounds. Euphorbia honeys obtained from different regions of Morocco were evaluated for their ability to inhibit acetylcholinesterase, lipoxygenase, tyrosinase and xanthine oxidase activities. Their antioxidant properties were evaluated using the: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity, nitric oxide scavenging activity (NO) and scavenging ability of superoxide anion radical. Then, the phenolic extracts of the same entire honey samples were evaluated by liquid chromatography coupled to diode array detection and mass spectrometry (LC-DAD-MS) and tested for the biological activities previously evaluated on the entire honeys, in order to conduct a comparative study between both (honey and phenolic extracts). The chromatographic profiles for the studied Euphorbia honey extracts were different. Phenolic compounds gallic acid, 4-hydroxybenzoic acid and p-coumaric acid were detected in all samples, whereas kampferol was only present in two samples. Physicochemical parameters and total phenolic content were also determined. Entire honey that recorded the highest rate of phenols was sample M6 (E. resinifera) = 69.25 mg GAE/100 g. On the other hand, the phenolic extracts had better antioxidant and enzyme inhibitory activities than the entire honeys, regardless the monofloral honey type. In conclusion, the studied Euphorbia honeys may have a great potential as antioxidant, anti-inflammatory and anti-tyrosinase sources for pharmaceutical and cosmetic applications.
- Leaf mineral element content and soil characteristics on in vitro antioxidant and enzymatic inhibitory activities of aqueous fennel extractsPublication . MAJDOUB, Nesrine; EL-GEUNDOUZ, Soukaina; Carlier, Jorge; Clara Costa, Maria; Guerrero, Carlos; Duarte, João; Miguel, Mariahis study was conducted to evaluate the biochemical characterization of three harvested Foeniculum vulgare plants collected from two bioclimatic zones in order to investigate the soil growing conditions effect. The results showed a great variability of the phenolic amounts and biological properties of samples rely on localities. FvSEN contained the highest amounts of phenolic compounds. These amounts were accompanied by the greatest antioxidant ability through almost studied assays. FvSEN and FvZO were significantly different. In addition, the samples exhibited a significant and variable enzymatic inhibition activity with values ranging from 30 to 50 mu g/mL for lipoxygenase assay. But these extracts did not revealed significant differences on their tyrosinase abilities. On the other hand, the levels of mineral elements were also estimated. These contents varied depending on sample and locality. The growing soil conditions of samples in terms of different parameters is likely related to their antioxidant and enzyme inhibition potentialities added to their mineral composition which settled by Spearman's correlation. These data may confirm the interesting potential of F. vulgare as a valuable source for natural antioxidant molecules but the growing soil conditions can affect all the potentialities of these plants set for human consumption and other uses.
- β-Cyclodextrin inclusion complexes of combined Moroccan Rosmarinus officinalis, Lavandula angustifolia and Citrus aurantium volatile oil: production optimization and release kinetics in food modelsPublication . El Kharraf, Sara; Farah, Abdellah; EL-GUENDOUZ, Soukaina; Lourenço, João P.; Rosa Da Costa, Ana; El Hadrami, El Mestafa; Machado, Alexandra M.; Tavares, Cláudia S.; Figueiredo, A. Cristina; Miguel, MGA combined volatile oil (VO) was extracted from Rosmarinus officinalis, Lavandula angustifolia and Citrus aurantium by simultaneous hydro- and steam-distillation, and encapsulated in beta-cyclodextrin by co-precipitation. Response surface methodology (RSM) was used to optimize microencapsulation conditions. The variable recovered powder, VO retention degree, and inclusion efficiency were investigated based on two factors: solid-to-liquid and liquid-to-liquid (ethanol/water) ratios. The responses were influenced by the concentration of ethanol in the reaction mixture and the amount of VO used. VO release from the inclusion complexes was investigated in 10% ethanol and in 3% acetic acid. The obtained data were fitted to the first-order Korsmeyer-Peppas, Higuchi, and Peppas-Sahlin models. The Higuchi model gave the fittest approach for the VO release profile in both cases, showing that the release mechanism was controlled by Fickian diffusion.
- Antioxidant activity and enzyme inhibitory potential of Euphorbia resinifera and E. officinarum honeys from Morocco and plant aqueous extractsPublication . Boutoub, Oumaima; EL-Geundouz, Soukaina; Estevinho, Leticia M.; Paula, Vanessa B.; Aazza, Smail; El Ghadraoui, Lahsen; Rodrigues, Brígida; Raposo, Sara; Carlier, Jorge; Costa, Maria Clara; Miguel, MariaNatural products may be applied in a wide range of domains, from agriculture to food and pharmaceutical industries. In this study, the antioxidant properties and the capacity to inhibit some enzymatic activities ofEuphorbia resiniferaandEuphorbia officinarumaqueous extracts and honeys were assessed. The physicochemical characteristics were also evaluated. Higher amounts of iron, copper and aluminium were detected inE. officinarumhoney, which may indicate environmental pollution around the beehives or inadequate storage of honey samples. This honey sample showed higher amounts of total phenols and better capacity for scavenging superoxide anion free radicals and DPPH free radicals as compared withE. resiniferahoney, but poorer capacity for inhibiting lipoxygenase, acetylcholinesterase, tyrosinase and xanthine oxidase. The ratio plant mass:solvent volume (1:100) and extraction time (1 - 2 h) were associated with higher total phenols and better antioxidant activities and lipoxygenase, acetylcholinesterase and tyrosinase inhibitory activities, regardless of the plant species. The aqueous extracts had systematically higher in vitro activities than the respective honey samples.
- Simultaneous Hydrodistillation-Steam Distillation of Rosmarinus officinalis, Lavandula angustifolia and Citrus aurantium from Morocco, Major Terpenes: Impact on Biological ActivitiesPublication . El Kharraf, Sara; Faleiro, Maria Leonor; Abdellah, Farah; EL-GUENDOUZ, Soukaina; El Hadrami, El Mestafa; Miguel, MariaInterest in the use of essential oils (EOs) in the biomedical and food industries have seen growing over the last decades due to their richness in bioactive compounds. The challenges in developing an EO extraction process that assure an efficient levels of monoterpenes with impact on biological activities have driven the present study, in which the EO extraction process of rosemary, lavender and citrus was performed by simultaneous hydrodistillation–steam distillation, and the influence of EO composition on biological activities, namely antioxidant, anti-inflammatory, antidiabetic, anti-acetylcholinesterase, anti-tyrosinase, antibacterial, and antibiofilm activity, were evaluated. The EO yields of combinations were generally higher than the individual plants (R. officinalis (Ro), L. angustifolia (La), and C. aurantium (Ca)) extracted by the conventional hydrodistillation. The EOs obtained by this process generally had a better capacity for scavenging the free radicals, inhibiting αglucosidase, and acetylcholinesterase activities than the individual EOs. The combination of EOs did not improve the ability for scavenging peroxide hydrogen or the capacity for inhibiting lipoxygenase activity. The antioxidant activity or the enzyme inhibition activity could not only be attributed to their major compounds because they presented lower activities than the EOs. The chemical composition of the combination Ro:La:Ca, at the ratio 1/6:1/6:2/3, was enriched in 1,8-cineole, linalool, and linalyl acetate and resulted in lower MIC values for all tested strains in comparison with the ratio 1/6:2/3:1/6 that was deprived on those components. The biofilm formation of Gram positive and Gram negative bacteria was impaired by the combination Ro:La:Ca at a sub-inhibitory concentration.
- Unassisted and carbon dioxide-assisted hydro- and Steam-distillation: modelling kinetics, energy consumption And chemical and biological activities of volatile oilsPublication . Sara, EL KHARRAF; EL-GUENDOUZ, Soukaina; Abdellah, Farah; El Hadrami, El Mestafa; Machado, Alexandra M.; Tavares, Cláudia S.; Figueiredo, Ana Cristina; Miguel, MariaThe demand for more suitable eco-friendly extraction processes has grown over the last few decades and driven research to develop efficient extraction processes with low energy consumption and low costs, but always assuring the quality of the volatile oils (VOs). The present study estimated the kinetic extraction and energy consumption of simultaneous hydro- and steam-distillation (SHSD), and SHSD assisted by carbon dioxide (SHSDACD), using an adopted modelling approach. The two isolation methods influenced the VOs yield, chemical composition and biological activities, namely, antioxidant, anti-glucosidase, anti-acetylcholinesterase and anti-inflammatory properties. SHSDACD provided higher VOs yields than the SHSD at a shorter extraction time: 2.8% at 30 min vs. 2.0% at 120 min, respectively, for Rosmarinus officinalis, 1.5% at 28 min vs. 1.2% at 100 min, respectively, for Lavandula angustifolia, and 1.7% at 20 min vs. 1.6% at 60 min, respectively, for Origanum compactum. The first order and sigmoid model fitted to SHSD and SHSDACD, respectively, with R2 value at 96% and with mean square error (MSE) < 5%, where the k distillation rate constant of SHSDACD was fivefold higher and the energy consumption 10 times lower than the SHSD. The rosemary SHSD and SHSDACD VOs chemical composition were similar and dominated by 1,8-cineole (50% and 48%, respectively), and camphor (15% and 12%, respectively). However, the lavender and oregano SHSDACD VOs were richer in linalyl acetate and carvacrol, respectively, than the SHSD VOs. The SHSDACD VOs generally showed better capacity for scavenging the nitric oxide and superoxide anions free radicals as well as for inhibiting α-glucosidase, acetylcholinesterase, and lipoxygenase.
- Insight into the chemical composition and biological properties of Mediterranean royal jellyPublication . EL-GEUNDOUZ, Soukaina; Lyoussi, Badiaa; Miguel, Maria da GraçaRoyal jelly (RJ) is a secretion of the hypopharyngeal and mandibular glands of young Apis mellifera worker bees. It is privileged for the queen bee as exclusive nourishment for her entire life. This bee hive product was used in traditional and folk medicine for human health care. Recently, there have been several research studies on RJ highlighting their therapeutic properties. It was found that it exhibits a large spectrum of biological and pharmacological potential including antibacterial, antioxidant, anti-inflammatory, immunomodulatory and antitumor activities among others, which might be of high importance in modern medicine for the development of new drugs. Even if RJ is known since ancient times; research papers concerning its investigation are not this much developed as compared to the other bee hive, products such as honey or propolis. In this review, we summarize our understanding of data found in literature about the chemical composition and biological properties of RJ, in particular, that which originates from Mediterranean countries to stimulate future studies. More attention should be given to this natural product for better comprehension of its mechanism of action in vitro and in vivo, for possible standardization and achievement of new formulations.