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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.
- Physicochemical characterization and antioxidant activity of honey with Eragrostis spp. pollen predominancePublication . AAZZA, Smail; Elamine, Youssef; EL-GEUNDOUZ, Soukaina; Lyoussi, Badiaa; Antunes, Maria Dulce; Estevinho, Leticia M.; Anjos, Ofélia; Carlier, Jorge; Costa, Maria C.; Miguel, MariaThis study aimed to characterize the pollen and physicochemical profiles, and to evaluate the antioxidant capacity of six samples of Moroccan honey. The pollen grains of Eragrostis spp. were predominant in all samples (from a minimum of 46.581.59% to 72.72 +/- 2.43% as a maximum), exceeding the minimum (generally 45%) required for the monoflorality nomination of a honey sample, and suggestion a case of newly reported honey. The analyzed samples had low diastase activity and hydroxymethylfurfural (HMF) content. Potassium was the dominant element in practically all samples, except the sample with the highest Eragrostis spp. pollen percentage, which showed sodium predominance. The honey color ranged from water white to light amber, and positively correlated the concentrations of phenols, proline and the capacity for scavenging free radicals. However, great variability observed in all the analyzed parameters, and could not be explained by the variability of the Eragrostis spp. pollen percentage, which suggests a hypothesis of low concentrated nectar. Practical applicationsThe melissopalynological profile of honey is an important parameter for determining the type of honey (multifloral, monofloral, blossom, honeydew) and its relationship to the botanical and geographical provenance. There is generally a relationship between the pollen profile of honey and the biological properties. The physicochemical characterization, antioxidant activity and melissopalynological profile of Eragrostis honey was reported for the first time in this study. These data intend to contribute for the introduction of a new type of honey labeled as Eragrostis honey. At the same time, the evaluation of the antioxidant activity may also trigger the search of other biological properties with medicinal attributes for the new Eragrostis ssp. honey.
- 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.
- Effect of poplar-type propolis on oxidative stability and rheological properties of O/W emulsionsPublication . EL-GEUNDOUZ, Soukaina; AAZZA, Smail; Lyoussi, Badiaa; MAJDOUB, Nesrine; Bankova, Vassya; Popova, Milena; Raposo, Sara; Antunes, Maria Dulce; Miguel, MariaPropolis is known to possess antioxidant activity. However, there is no information on this activity in emulsions O/W. The protective effect of propolis on the oxidation and rheological properties of emulsions O/W containing wheat germ and almond oils was evaluated. Emulsions O/W were prepared with different concentration of propolis extract, almond oil and wheat germ oil. All emulsions physically stable without phase separation were stored at 37 °C for 9 weeks. Chemical composition of propolis was established by Gas chromatography coupled to mass spectrometry. Rheological characterization of different emulsions was performed evaluating consistency index and flow behavior index. The oxidation was monitored by measuring the lipid hydroperoxides and thiobarbituric acid-reactive substances (TBARS) methods. Flavonoids, phenolic acid esters, and aromatic acids were the main groups of compounds found in propolis. The results showed that popolis was good antioxidant in the concentration of 0.02 and 0.04% when lipid phase was constituted by almond oil. The rheological behavior is typical of a non-Newtonian fluid, being almond oil more adequate for having a higher stable O/W emulsion.
- 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.
- Anti-acetylcholinesterase, antidiabetic, anti-inflammatory, antityrosinase and antixanthine oxidase activities of Moroccan propolisPublication . EL-GEUNDOUZ, Soukaina; S, Azza; Lyoussi, Badiaa; Antunes, Maria Dulce; Faleiro, Maria Leonor; Miguel, MariaBiological properties of Moroccan propolis have been scarcely studied. In the present work, the total phenols and flavonoids from 21 samples of propolis collected in different places of Morocco or 3 supplied in the market were determined, as well as the invitro capacity for inhibiting the activities of acetylcholinesterase, -glucosidase, -amylase, lipoxygenase, tyrosinase, xanthine oxidase and hyaluronidase. The results showed that samples 1 (region Fez-Boulemane, Sefrou city) (IC50=0.065, 0.006, 0.020, 0.050, 0.014mgmL(-1)) and 23 (marketed) (IC50=0.018, 0.002, 0.046, 0.037, 0.008mgmL(-1)) had the best invitro capacity for inhibiting the -amylase, -glucosidase, lipoxygenase, tyrosinase and xanthine oxidase activities, respectively. A negative correlation between IC50 values and concentration of phenols, flavones and flavanones was found. These activities corresponded to the generally higher amounts of phenols and flavonoids. In the same region, propolis samples have dissimilar phenol content and enzyme inhibitory activities.
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