Browsing by Author "Elamine, Youssef"
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- Antibacterial activity of Moroccan Zantaz Honey and the influence of its physicochemical parameters using chemometric toolsPublication . Elamine, Youssef; Imtara, Hamada; Miguel, Maria; Anjos, Ofélia; Estevinho, Letícia M.; Alaiz, Manuel; Girón-Calle, Julio; Vioque, Javier; Martín, Jesús; Lyoussi, BadiâaThe emergence of multidrug-resistant bacteria has prompted the development of alternative therapies, including the use of natural products with antibacterial properties. The antibacterial properties of Zantaz honey produced in the Moroccan Atlas Mountains against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus was evaluated and analyzed using chemometric tools. Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) against S. aureus were the lowest (112.5 ± 54.5 mg/mL), revealing that this species was most sensitive to Zantaz honey. P. aeruginosa showed an intermediate sensitivity (MIC= 118.75 ± 51.9 mg/mL), while E. coli was the most resistant to treatment (MIC = 175 ± 61.2 mg/mL). Content of monosaccharides, certain minerals, and phenolic compounds correlated with antibacterial activity (p < 0.05). Principal component analysis of physicochemical characteristics and antibacterial activity indicated that the parameters most associated with antibacterial activity were color, acidity, and content of melanoidins, fructose, epicatechin, methyl syringate, 4-coumaric acid, and 3-coumaric acid.
- Electrical impedance spectroscopy for potassium content analysis and botanical origin identification of honeyPublication . Elamine, Youssef; INÁCIO, PEDRO; Miguel, Maria da Graça; Carlier, Jorge; Costa, Maria Clara; Estevinho, Leticia M.; Gomes, Henrique L.Minerals are reported to dominate the electrical properties of honey and indicate its botanical and geographical origins. In this study, Electrochemical Impedance Spectroscopy (EIS) was used to assess the relation between mineral elements, electrical properties and botanical origin using three honey varieties - Citrus sp., Eucalyptus sp., and Erica sp. These varieties are identified through pollen analysis and market labelling. Flame atomic absorption and emission spectroscopies were used to quantify the concentrations of eight elements (potassium, sodium, calcium, magnesium, manganese, zinc, copper, and iron). Among all the mineral elements, potassium showed a consistent correlation with impedance. The potassium estimation in honey and standard solutions (calibration curve) had similar sensitivities of 153.43 nF/mM and 132.68 nF/mM, respectively. Additionally, the analysis revealed that potassium dominates the mineral composition, with the other species present in minimal quantities. The EIS technique showed high sensitivity to potassium and other ionisable species, making it possible to classify the botanical origin of these three honey types. The EIS technique proved to be both time and cost effective, yielding a classification rate higher than that achieved by analysing mineral composition.
- Exploring Caralluma europaea (Guss.) NEBr. as a potential source of bioactive molecules: In vitro antioxidant and antidiabetic properties, and phenolic profile of crude extracts and fractionsPublication . Dra, Loubna Ait; Rodrigues, Maria Joao; Neng, Nuno da Rosa; Nogueira, Jose M. F.; Elamine, Youssef; Aghraz, Abdellah; Markouk, Mohamed; Larhsini, Mustapha; Custódio, LuísaCaralluma europaea (Guss.) N.E.Br is a succulent medicinal species used in the Moroccan traditional medicine for its anticancer and antidiabetic properties. In this work, this species was explored for the in vitro antidiabetic and antioxidant properties of crude methanol and dichloromethane extracts, and obtained fractions, from its aerial organs. In vitro antidiabetic properties were evaluated towards baker's yeast and rat's intestinal alpha-glucosidase, and alpha-amylase. Four in vitro methods were used to appraise the antioxidant potential, namely radical scavenging activity (RSA) on 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and iron and copper chelating assays. Finally, the profile of the main phenolic compounds present in the samples was assessed by high-performance liquid chromatography equipped with diodearray detection (HPLC-DAD). The highest inhibition of baker's yeast alpha-glucosidase was obtained with the methanol extract (87%), and its fractions, with a maximum inhibition of 83% at the concentration of 10 mg/ml. The most significant inhibition of mammalian alpha-glucosidase was obtained with the dichloromethane crude extract (85%), and corresponding fractions at 10 mg/ml. Moderate activity was achieved with the two extracts against a-amylase (52-53%) at 10 mg/ml, but no relevant activity was detected for most fractions. Crude extracts had a significant RSA against DPPH and ABTS, with range values of 83-98% (methanol extracts) and 53-80% (dichloromethane extracts). Fractions from the methanol extract were more active against tested radicals. Crude extracts had chelating activity on both metals, and the highest copper chelation was achieved with the methanol extract, while the dichloromethane extract and the majority of fractions from both extracts presented the highest iron chelation at 10 mg/ml. A total of 21 phenolic compounds were identified and quantified by HPLC-DAD in the samples, and the main compounds detected were catechine hydrate and salicylic and caffeic acids. Our results suggest that C. europaea extracts contain compounds with in vitro antioxidant and antidiabetic properties with potential applications in the pharmaceutical and food industries.
- A meta-taxonomic investigation of the prokaryotic diversity of water bodies impacted by acid mine drainage from the São Domingos mine in southern PortugalPublication . Ettamimi, Sara; Carlier, Jorge; Cox, Cymon J.; Elamine, Youssef; Hammani, Khalil; Ghazal, Hassan; Costa, Maria ClaraThe prokaryotic communities of water bodies contaminated by acid mine drainage from the São Domingos mining area in southern Portugal were analyzed using a meta-taxonomics approach with 16S rRNA gene sequences. Samples were collected in two seasonal sampling campaigns (summer and winter of 2017) from the most contaminated sites from where the water flows downstream to the freshwater reservoir of the river Chança. The physicochemical data indicate a trend of decreasing acid mine drainage contamination downstream of the mining area to the Chança's reservoir. The most contaminated sites (pH = 2.3-3.1) are distinguished by prokaryotic diversity with high abundances of operational taxonomics units related to acidophiles (genera Metallibacterium, Acidibacter, Leptospirillum, Acidobacterium, Thiomonas, Acidicapsa, Acidocella, Acidiphilium; family Acidobacteriaceae, order CPla-3 termite group). Likewise, in the transition zone in the mouth of the contaminated water flow into the Chança´s reservoir (pH = 6.4), a specific prokaryotic flora exists with some acidophiles, but notably with a cyanobacteria bloom and a high abundance of the genus Sediminibacterium (family I; order Subsection III). Moreover, the strong correlation between the abundance of acidophiles and characteristic physiochemical parameters (metals, acidity, and sulfate) confirm their potential as biomarkers of acid mine drainage pollution.
- Physicochemical characteristics and antiproliferative and antioxidant activities of Moroccan Zantaz honey rich in methyl syringatePublication . Elamine, Youssef; Lyoussi, Badiaa; Miguel, Maria G.; Anjos, Ofelia; Estevinho, Leticia; Alaiz, Manuel; Giron-Calle, Julio; Martin, Jesus; Vioque, JavierZantaz honey is a monofloral variety produced from the melliferous plant Bupleurum spinosum (Apiaceae), a shrub that grows mainly in the Atlas Moroccan Mountains. Determination of the polyphenol composition revealed that methyl syringate accounts for more than 50% of total polyphenols, which represents a very useful parameter for the characterization of this monofloral honey. Epicatechin, syringic acid and catechin are also abundant. Caco-2 and THP-1 cells were used for determination of antioxidant and antiproliferative activities in Zantaz honey, respectively. All six commercial samples that were used for these studies exhibited antioxidant activity and inhibited cell proliferation. Interestingly, these activities had a positive correlation mainly with the content in methyl syringate and gallic acid. The recognition of health promoting activities in Zantaz honey should increase its commercial value, which would have a positive economic impact on the poor rural communities of Morocco where it is produced.
- 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.
- Volatile characterization of honey with dominance of Bupleurum spinosum pollenPublication . Elamine, Youssef; Machado, Alexandra M.; Estevinho, Letícia M.; Lyoussi, Badiâa; Figueiredo, Ana Cristina; Miguel, MariaMoroccan honey with Bupleurum spinosum (Apiaceae/Umbelliferae) as the main pollen source is locally known as Zantaz honey. In the present work, the volatiles from 18 honeys of this type, were isolated by hydrodistillation and analysed by Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS), for volatiles quantification and identification. The percentage composition of the volatiles and pollen profiling was used to determine the relationship between the different samples by cluster analysis. Two poorly correlated clusters were defined in volatiles analysis. Cluster A, with 17 out of the 18 samples, included four subgroups dominated by straight-chain hydrocarbons and fatty acids in variable proportions. Cluster B included just one sample, with 1-phenyldodec-1-en-3-one as the main component. Mono- and sesquiterpene hydrocarbons, as well as oxygen-containing mono- and sesquiterpenes occurred always B. spinosum and Populus sp. pollen. The one sample from Cluster B was moderately correlated with Cluster A and showed the lowest percentage of B. spinosum pollen. Pollen volatiles analysis would be relevant in assessing the presence of putative pollen volatile marker compounds and the importance of pollen profile on honey volatiles.