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- Antioxidant and anti-lipoxygenase activities of extracts from different parts of Lavatera cretica L. grown in Algarve (Portugal)Publication . Ben Nasr, S.; S, Azza; Mnif, W.; Miguel, Maria GraçaBackground: Lavatera cretica L. was used in folk medicine as anti-inflammatory among other applications. As inflammation is many times associated with oxidative processes, the aim of the present work was to evaluate the ability of aqueous extracts obtained from different parts of L. cretica to prevent oxidation or inflammation using several methods in vitro. Materials and Methods: The capacity of samples for preventing lipid peroxidation, scavenging free radicals, chelating metal ions, reducing power, and inhibiting lipoxygenase activity was investigated. This last assay also permits to evaluate the anti-inflammatory activity. The quantification of total phenols was performed using Folin-Chiocalteu reagent. Results: The highest concentrations of total polyphenols and flavonoids were found in the leaf extract (254.62 6.50 mg gallic acid equivalent/gram; dry weight). Leaf and flower extracts were the most active for scavenging 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt free radicals [Inhibition concentration (IC 50 = 2.88 0.54 and IC50 = 4.37 0.54 g/mL, respectively)], and leaf extract was also the best for scavenging hydroxyl radicals (IC 50 = 0.81 0.05 g/mL). Bract plus sepal extract possessed the best capacity for preventing lipid peroxidation when lecithin liposome was the lipid substrate (IC 50 = 0.19 0.03 g/mL) and scavenging superoxide anion radicals (IC 50 = 1.13 0.48 g/mL). Leaf and flower extracts were the best lipoxygenase inhibitors (IC 50 = 0.013 0.0034 g/mL in both extracts). Conclusions: L. cretica extracts were able to scavenge free radicals, inhibit lipid peroxidation and lipoxygenase activity. With these attributes, this plant can have an important role in the treatment of neurodegenerative disorders.
- Anti-oxidant, Anti-inflammatory and Anti-proliferative Activities of Moroccan Commercial Essential OilsPublication . S, Azza; Lyoussi, B.; Megias, C.; Cortes Giraldo, I.; Vioque, J.; Figueiredo, A. C.; Miguel, Maria GraçaEssential oils (EO) possess antimicrobial, anti-inflammatory, insect repellent, anti-cancer, and antioxidant properties, among others. In the present work, the antioxidant, anti-inflammatory and anti-proliferative activities of Moroccan commercial EOs (Citrus aurantium, C. union, Cupressus sempervirens, Eucalyptus globulus, Foeniculum vulgare and Thymus vulgaris) were evaluated and compared with their main constituents. T. vulgaris EO showed the best free radicals scavenging capacity. This EO was also the most effective against lipid peroxidation along with C. limon and F. vulgare EOs. C. sempervirens EO was the most effective in scavenging NO free radicals, whereas C. limon EO showed the best chelating power. Not all of the major compounds of the EO were responsible for the whole activity of the EOs. T. vulgaris EO showed the best anti-proliferative activity against THP-1 cells in contrast to that of F. vulgare. The antioxidant and anti-inflammatory activities of the EOs were plant species dependent and not always attributable to the EOs main components. Nevertheless, the EOs anti-proliferative activities were more related to their main components, as with T. vulgaris, C. limon, E. globulus and C. sempervirens.
- Physicochemical Characterization and Antioxidant Activity of Commercial Portuguese HoneysPublication . AAZZA, Smail; Lyoussi, B.; Antunes, Maria Dulce; Miguel, Maria GraçaThe present study evaluated the physicochemical characteristics and antioxidant activity of 13 commercial honeys from diverse floral origin, produced in Portugal. The values of electrical conductivity of cardoon and pennyroyal honeys were superior to the maximum limits defined by European legislation. Citrus, strawberry tree, and 1 sample of lavender honeys had values of diastase activity below those determined by European legislation. Strawberry tree, pennyroyal, and cardoon honeys had the highest amounts of potassium that coincided with the highest electrical conductivity. Strawberry tree honey was the most effective as antioxidant along with cardoon and heather honeys. This ability was strongly correlated with the amounts of phenols and flavonoids and not with the levels of vitamin C or proline.
- Mineral and volatile composition of agua-mel from PortugalPublication . Miguel, Maria Graça; AAZZA, Smail; Antunes, Maria Dulce; Faleiro, Maria Leonor; Barroso, José G.; Pedro, Luis G.; Figueiredo, A. CristinaAgua-mel (honey-water) is a typical honey-based product produced by the Portuguese beekeepers, particularly in southern Portugal. Agua-mel was characterized by mineral content and volatiles contents. Mineral content evaluation was performed based on a random sampling of 14 samples from a total of 16 samples provided by local producers. Mineral content showed that potassium predominated in agua-mel samples (1270-4105 mg/kg). The concentration of aluminium in one sample was tenfold higher (5.8 mg/kg) than in the remaining samples (0.3-0.6 mg/kg). Agua-mel volatiles were isolated by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) from a subset of eight samples. Cluster analysis showed two poorly correlated clusters (S (corr) < 0.3). Cluster I only sample was dominated by trans-beta-ocimene (19 %), gamma-terpinene (15 %) and 2-furfural (9 %). Cluster II that included the remaining seven samples showed two moderately correlated subclusters (S (corr) < 0.5). The six samples with high correlation from subcluster IIa were dominated by 2-furfural (18-41 %) and benzene acetaldehyde (12-39 %). n-Nonadecane (14 %), n-heneicosane and 2-furfural (both 13 %) were the main components of subcluster IIb sample. Although the presence of some volatile compounds can help in the correlation between agua-mel and honey botanical source, the final product varies largely according to the preparation process even for the same producer, in different years. Agua-mel detailed characterization may assist in bringing added value to this typical Portuguese honey-based product.
- Antioxidant activity of eight hydrosols from MoroccoPublication . S, Azza; Lyoussi, B.; Miguel, Maria GraçaEssential oils from aromatic and medicinal plants have received particular attention as potential natural agents for food preservation and medicine. Nevertheless, much less attention has been given to the components which remain dissolved in the distillation water. To this fraction which is quite fragrant and strongly flavoured with values of pH ranging from 4.5-5.5 is called hydrosol. The antioxidant activity of hydrosols produced by an enterprise from Morocco from eight aromatic species (Pelargonium graveolens, Artemisia herba-alba, Cupressus atlantica, Ocimum basilicum, Juniperus phoenicea, Pinus pinaster, Marrubium vulgare and Hyssopus officinalis) was evaluated. Several methods were used: Thiobarbituric acid Reactive Species (TBARS), Trolox Equivalent Antioxidant Capacity (TEAC), hydroxyl and superoxide scavenging abilities. The results showed that in TBARS and superoxide scavenging ability, H. officinalis hydrosol revealed to be the most effective (IC50 = 136 mg mL-1 and IC50 = 2 mg mL-1, respectively). In the TEAC assay, M. vulgare was the most effective (IC50 = 72 mg mL-1), although H. officinalis also presented a good activity ((IC50 = 87 mg mL-1). A. herba-alba hydrosol presented the best capacity for scavenging hydroxyl free radical (IC50 = 95 mg mL-1). © 2012 Asian Network for Scientific Informatio.
- Antioxidant activities of eight Algerian plant extracts and two essential oilsPublication . Boulanouar, B.; Abdelaziz, G.; S, Azza; Gago, Custódia; Miguel, Maria GraçaTotal phenol, hydroxycinnamic acid derivatives, flavone/flavonol and flavanones/dihydroflavonol contents of hydro-alcoholic extracts, obtained by sonication, from the aerial parts of Artemisia campestris L., Anthemis arvensis L., Haloxylon scoparium Pomel, Juniperus phoenicea L., Arbutus unedo L., Cytisus monspessulanus L., Thymus algeriensis Boiss et Reut, Zizyphus lotus L (Desf.) collected in Djebel Amour (Sahara Atlas, Algeria) were quantified by spectrophotometric methods. The chemical composition of the essential oils obtained by hydrodistillation from Artemisia campestris L. and Juniperus phoenicea I aerial parts were also evaluated by gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC-MS). The antioxidant activity of the extracts and essential oils was assessed measuring the capacity for preventing lipid peroxidation using two lipidic substrates (egg yolk and liposomes), the capacity for scavenging DPPH, ABTS, superoxide anion radicals, hydroxyl radicals and peroxyl radicals. Anti-inflammatory activity was assessed by measuring the capacity for inhibiting lipoxygenase. Reducing power and chelating capacity were also assayed. The results showed different amounts of total phenols depending on the method used: A. campestris extract had the highest levels of total phenols when the measurement was made at lambda = 280 nm, whereas H. scoparium and A. unedo extracts showed the highest levels of total phenols with Folin-Ciocalteau. C. monspessulanus had the highest levels of flavones/flavonols and flavanones/dihydroflavonols. The essential oils of A. campestris and J. phoenicea were mainly constituted by alpha-pinene, beta-pinene and sabinene; and a-pinene, respectively. The methods used for assaying the capacity for preventing lipid peroxidation revealed to be inadequate for extracts due to the great interferences detected. The essential oils were more active than the generality of extracts for scavenging peroxyl radicals and for inhibiting lipoxygenase, whereas A. unedo extract was the most active for scavenging ABTS, DPPH, superoxide anion radicals and it also had the best reducing capacity. In a general way, the great majority of the antioxidant activities correlated well with the phenol content although such correlation was not so clear with the flavonoid content. (c) 2013 Elsevier B.V. All rights reserved.
- Antioxidant, anti-inflammatory and anti-acetylcholinesterase activities of eleven extracts of Moroccan plantsPublication . Miguel, Maria Graça; Bouchmaa, N.; S, Azza; Gaamoussi, F.; Lyoussi, B.The capacity of ethanolic extracts of wHaloxylon scoparium Pomel, Corrigiola telephiifolia Pourr., Ammodaucus leucotrichus Cosson & Durieu subsp. leucotrichus, Chamaerops humilis L., Sideritis arborescens Salzm. ex Benth., Ammi visnaga (L.) Lam., Vitex agnus castus L., Retama raetam (Forssk.) Webb & Berthel., Berberis vulgaris L., Viscum album L., and Equisetum arvense L. from Morocco to prevent lipid peroxidation, scavenging free radicals, inhibiting lipoxygenase and acetylcholinesterase activities, were evaluated and compared to those reported in the literature. As far as we know, the present work was the first reporting on the antioxidant ability of S. arborescens. The results showed that Equisetum arvense and Sideritis arborescens (stems) possessed the highest concentrations of total phenols and flavonoids, respectively, and the extracts of Berberis vulgaris and Viscum album were the most promising as antioxidants as well as anti-inflammatory and acetylcholinesterase (AChE) inhibitors. In some cases, the activities of B. vulgaris extracts were not significantly different from those found for positive control (e.g. capacity for scavenging free radicals, and capacity for inhibiting AChE).
- Antimicrobial, antiviral and antioxidant activities of ‘‘água-mel’’ from PortugalPublication . Miguel, Maria Graça; Faleiro, Leonor; Antunes, Maria Dulce; S, Azza; Duarte, Joana; Silvério, Ana R.‘‘Água-mel’’ is a honey-based product produced in Portugal for ancient times. Several attributes have been reported to ‘‘água-mel’’ particularly in the alleviation of simple symptoms of upper respiratory tract. Samples of ‘‘água-mel’’ from diverse beekeepers from different regions of Portugal were studied in what concerns antimicrobial, antioxidant and antiviral properties. The amounts of phenol and brown pigment were also evaluated and correlated with the antioxidant activities. A great variability on the levels of these compounds was found among samples which were responsible for the variability detected also on the antioxidant activities, independent on the method used. Generally, antioxidant activity correlated better with brown pigments’ amount than with phenols’ content. The antimicrobial activity found for ‘‘água-mel’’ samples confirm the virtues reported by popular findings. In addition, this work also reveals the antiviral properties of ‘‘água-mel’’ evidenced by a decrease on the infectivity of the Qb bacteriophage.
- Antioxidant and Antiacetylcholinesterase Activities of Some Commercial Essential Oils and Their Major CompoundsPublication . S, Azza; Lyoussi, B.; Miguel, Maria GraçaThe commercial essential oils of Citrus aurantium L., Cupressus sempervirens L., Eucalyptus globulus Labill., Foeniculum vulgare Mill. and Thymus vulgaris L., isolated by steam distillation by a company of Morocco were evaluated in terms of in vitro antioxidant activity through several methods. In vitro acetylcholinesterase inhibitory activity was also determined. Citrus limon (L.) Burm. f. oil was also studied, but it was obtained by peel expression. The best antioxidant was T. vulgaris oil, independent of the method used, mainly due to the presence of the phenolic monoterpenes thymol and carvacrol, which when studied as single compounds also presented the best activities. Concerning the acetylcholinesterase inhibition activity, E. globulus was the most effective. Nevertheless its main components 1,8-cineole and limonene were not the most active, a feature that corresponded to delta-3-carene.
- Antioxidant activity of some Morrocan hydrosolsPublication . S, Azza; Lyoussi, B.; Miguel, Maria GraçaEssential oils are used in Cosmetic, Perfumery, Food and Pharmaceutical Industries as flavours and/or medicines. However, part of the essential oil components that remains in the distillation water (hydrosol or distillate water) has been less studied both in chemical and biological terms. This research concerns the antioxidant activity, measured through several methods, of Lavandula officinalis L., Origanum majorana L., Rosmarinus officinalis L., Salvia officinalis L. and Thymus vulgaris L., Cinnamomum verum J. Presl. and Syzygium aromaticum (L.) Merrill and Perry hydrosols. The ability of hydrosols to prevent oxidation was checked by two main methods: prevention of lipid peroxidation through the measurement of malonaldehyde produced after degradation of hydroperoxides; and ability for scavenging free radicals including hydroxyl and superoxide anion radicals. The S. aromaticum and T. vulgaris hydrosols, predominantly constituted by eugenol and carvacrol, respectively, were the most effective as antioxidants, except for scavenging superoxide anion radical. In this case, L. officinalis hydrosol in which linalool prevailed was a stronger antioxidant. The worst hydrosol as antioxidant was that of S. officinalis, independent on the method checked.