Sami Zouari - Academia.edu (original) (raw)

Papers by Sami Zouari

International Journal of Food Properties, Mar 1, 2012

This study deals with the chemical characterization of a medicinal and an aromatic plant of the T... more This study deals with the chemical characterization of a medicinal and an aromatic plant of the Tunisian flora: Allium roseum var. odoratissimum, and aimed to identify new bioactive natural compounds in its flower essential oil. These compounds were extracted by hydrodistillation and were analyzed by GC and GC/MS, using an apolar column. The most important compounds characterized were organo-sulphurous (46%),

Le rendement et la composition chimique des huiles essentielles, isolees par hydrodistillation, d... more Le rendement et la composition chimique des huiles essentielles, isolees par hydrodistillation, des parties aeriennes de differents populations de Th. capitatus collectees durant la phase vegetative, de floraison et de fructification, a partir de 3 differents sites en Tunisie (interieur et littoral nord et littoral sud), ont ete mesures et analyses par GC et GC-MS. Toutes les populations etudiees fournissent une huile jaunâtre a des rendements variants de 1-5% (g/g) au stade floral. Carvacrol (55-86%), p-cymene (3-17%), γ-terpinene (1-17%), thymol (0.2-13%) et β-caryophyllene (1-4%) sont, a des taux variables, les composes majeurs de cette huile. L'analyse statistique de la composition chimique des huiles essentielles confirme une homogeneite chimique majeure avec un coefficient de correlation>0.978.

Food and Bioproducts Processing, Oct 1, 2011

The present study describes chemical composition, angiotensin I-converting enzyme (ACE) inhibitor... more The present study describes chemical composition, angiotensin I-converting enzyme (ACE) inhibitory, antioxidant and antimicrobial activities of the essential oil of wild growing Thymus algeriensis Boiss. et Reut. (Lamiaceae), a traditional medicinal plant which is mainly endemic in Tunisia and Algeria. The essential oil from the fresh leaves and flowers of T. algeriensis were extracted by hydrodistillation and analysed by GC

Molecules

Peppers are among the spices possessing a wide plethora of biological properties due to their exc... more Peppers are among the spices possessing a wide plethora of biological properties due to their excellent supply of health-related metabolites. Capsicum annuum L. (Solanaceae) is cultivated throughout Tunisia, and there is a shortage of information on the identification of the secondary metabolites in the seeds of this species as well as on their biological activities. In the present work, we intended to undertake a chemical characterization of the bioactive compounds from the hydro-methanolic seed extract of C. annuum as well as an evaluation of its broad spectrum of antimicrobial and antioxidant activities. The chemical profile was evaluated by RP-HPLC-DAD-QTOF-MS/MS, whereas the total phenol and flavonoid content, antioxidant, and antimicrobial activities were determined in in vitro assays. In this work, 45 compounds belonging to various phytochemical classes, such as organic acids (2), phenolic compounds (4 phenolic acids and 5 flavonoids), capsaicinoids (3), capsianosides (5), fa...

Microbial Pathogenesis, 2016

Plant extracts, and their essential oils (EOs) are rich in a wide variety of secondary metabolite... more Plant extracts, and their essential oils (EOs) are rich in a wide variety of secondary metabolites with antimicrobial properties. Our aim was to determine the bioactive compound in three mediterranean essential oils belonging to Lamiaceae family, Satureja montana L., Thymus vulgaris L. and Rosmarinus officinalis L., and to assess their antimicrobial, antibiofilm and anti-adhesive potentials against a foodborne pathogen Salmonella strain. The antibacterial activity of EOs and its biofilm inhibition potencies were investigated on 2 reference strains Salmonella typhimurium and 12 Salmonella spp. isolated from food. Biofilm inhibition were assessed using the 2, 3-bis [2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT) reduction assay. The analytical data indicated that various monoterpene hydrocarbons and phenolic monoterpenes constitute the major components of the oils, but their concentrations varied greatly among the oils examined. Our results showed that S. montana L. and T. vulgaris L. essential oils possess remarkable anti biofilm, anti-adhesive and bactericidal properties, compared to R. officinalis EO. There is an indication that Rosmary EO might inhibit biofilm formation at higher concentrations. Therefore, the witer savory and thyme EOs represent a source of natural compounds that exhibit potentials for use in food systems to prevent the growth of foodborne bacteria and extend the shelf life of the processed food.

Pharmacognosy Communications, 2015

Pituranthos chloranthus, commonly known in Arabic as 'Aljen,' is a small aromatic plant which gro... more Pituranthos chloranthus, commonly known in Arabic as 'Aljen,' is a small aromatic plant which grows spontaneously in North Africa and it is widespread in central and southern Tunisia. This paper is the first report of its kind on the isolation and characterization of certain coumarin derivatives from the extract of the roots and aerial parts of this plant. Background: Pituranthos chloranthus (Apiaceae) commonly known as 'Aljen' is an endemic Tunisian aromatic plant, largely used in folk medicine. This plant contains bioactive compounds, particularly coumarin derivatives. The objective of the present study was to isolate and characterize some bioactive phytochemical constituents from the extract of the aerial parts and roots of Pituranthos chloranthus. Methods: Different extracts were subjected to column chromatography and eluted with solvent mixtures of increasing polarity (petroleum ether, ethyl acetate and methanol) to isolate five pure Products. The structure of the isolated compound was established using spectroscopic methods (UV, 1 H-NMR, 13 C-NMR, DEPT, HMBC, HSQC, COSY), and HRMS. Results: Isoimperatorin, osthol and oxypeucedanin were isolated from the n-hexane and ethyl acetate extract of the aerial part of the plant. Bergapten and nodakenetin were isolated from the methanolic extract of the roots. Conclusion: Pituranthos chloranthus contains bergapten, isoimperatorin, nodakenetin, osthol and oxypeucedanin which may be responsible for various pharmacological activities of the plant.

Acta Botanica Gallica Bulletin De La Societe Botanique De France, Apr 26, 2013

ABSTRACT This study deals with the valorisation of medicinal and aromatic Allium to find new bioa... more ABSTRACT This study deals with the valorisation of medicinal and aromatic Allium to find new bioactive natural products. The phytochemical analyses of A. roseum and A. ampeloprasum powders and their aqueous and organic extracts are achieved. The results show that these species are characterized by the presence, among their components, of three precursors of organosulphurous volatile compounds. They are methiin, isoalliine and alliine in A. roseum and isoalliin and methiin in A. ampeloprasum. These differences in their flavours can correlated with the vicinity of A. roseum with garlic and A. ampeloprasum with onion. Phytochemical screening of Allium roseum shows the presence of active agents such as saponins, tannins, flavonoids, coumarins, steroids, cardiac glycosides, free quinone and iridoids.

Data Revues 16310748 00100009 07000835, Feb 14, 2008

Journal of Essential Oil Research, 2015

Journal of Essential Oil Bearing Plants, 2013

ABSTRACT Periploca angustifolia Labill. is a multipurpose (ecological, pastoral and therapeutic) ... more ABSTRACT Periploca angustifolia Labill. is a multipurpose (ecological, pastoral and therapeutic) native shrub of the Mediterranean basin. Periploca leaves were used, for a long time, by the local population as decoction or infusion to treat digestive disorders. Root bark, known by their hypotensive property, is used as infusion with the tea. The resin, exuded by roots after section, is used as masticator having a good smell when burned. The ethnobotanical value of this shrub incited us to develop the present work having as objective to determine the chemical composition of the root bark of P. angustifolia, at the flowering stage. The main results of the phytochemical screening showed the presence of C-Heterosids (Anthracenic derivatives), anthocyans, saponins, free quinons and proanthocyanidols. Quantitative analysis of P. angustifolia's root bark, showed that it has relatively high amount on crude proteins (1.46 mg/g DM) and fatty matter (1.05 mg/g DM), as well as some secondary metabolites such us condensed tannins (3189.8 mgCE/100g DM), polyphenol content (2.6 mgGAE/g DM), carotenoids (0.27 mg/g DM), anthocyanins (1.8 mg/g DM) and flavonoids (4.1 mgQE/g DM). The analysis by Gas Chromatography-Mass Spectrometry (GC-MS) revealed many volatiles such as 2-hydroxy-4-methoxybenzaldehyde as it is the major compound (89.23 %).

Journal of Essential Oil Bearing Plants, 2014

ABSTRACT Chemical composition, antimicrobial activity and antioxidative proprieties were assessed... more ABSTRACT Chemical composition, antimicrobial activity and antioxidative proprieties were assessed in air-dried shoots of Haplophyllum tuberculatum. Samples were subjected either to organic fractionated extraction (hexane, chloroform and methanol) or hydrodistillation for essential oil extraction. We found that methanol extract (ME) was the most enriched in polyphenols and that flavonoïds were more concentrated in chloroform one (CE). Antimicrobial tests showed that organic extracts were more effective against Gram negative bacteria than Gram positive ones. The best antibacterial activity was exhibited by ME which was also active against Candida albicans. Gas chromatography/mass spectrometry analysis of extracted essential oil from air-dried shoots revealed 18 indentified components representing 93.46 % of total oil. The major components were hexadecanoic acid (40.21 %) and oleic acid (26.75 %). Antioxidative assays showed that H. tuberculatum essential oil exhibited a weak ferric reducing power and moderate free radical scavenging activity. Obtained data argued that H. tuberculatum shoots are sources of natural products of promising antimicrobial and antioxidative capacities.

Journal of Biologically Active Products from Nature, 2012

ABSTRACT Medicinal plants constitute an important source for a wide variety of natural antioxidan... more ABSTRACT Medicinal plants constitute an important source for a wide variety of natural antioxidants. Therefore, the aim of the present work was to compare the antioxidant activities, total phenolic and flavonoid contents of three wild populations of Marrubium vulgare L. The plant was collected from the South-East (Matmata and Thoujene) and the Central-Sahel (Melloulech) of Tunisia, at the vegetative and at the fruiting stages. The antioxidant activities were evaluated by the following methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, reducing power and metal (Fe2+) chelating activity. Ethanolic extract of M. vulgare present the highest contents of phenolics (267–325 mg GAE/g extract) and flavonoids (212–245 mg QE/g extract) at the fruiting stage, regardless the geographical location. Furthermore, the highest antioxidant activities were also obtained at the fruiting stage of M. vulgare.

Analytical Chemistry Letters, 2011

Arabian Journal of Chemistry, 2013

Nutritional composition, antioxidant and antibacterial properties of Terfezia boudieri Chatin, a ... more Nutritional composition, antioxidant and antibacterial properties of Terfezia boudieri Chatin, a desert truffle largely distributed in Southern Tunisia were evaluated. Carbohydrates were the most abundant macronutrients (62.03 g/100 g) followed by proteins (26.12 g/100 g) in T. boudieri truffle (dry mass). The ash content was 4.49 g/100 g dry mass and potassium, phosphorus, iron, and calcium were found to be particularly abundant in T. boudieri. The fat content of the truffle was 8 g/100 g dry mass, characterized by its higher content of the essential linoleic acid (n-6) (54.18%). Eight volatile compounds were identified by GC and GC/MS and they were dominated by fatty acids. The results of ascorbic acid, total carotenoids and total anthocyanins expressed on a truffle dry mass were 12.20 mg/100 g, 1.43 mg/100 g and 35.40 mg/100 g, respectively. The methanolic extract, containing the highest amounts of phenolics and flavonoids, displayed the highest DPPH radical-scavenging activity (IC 50 = 0.20 mg/ml) and the lipid peroxidation inhibitory activity (IC 50 = 0.36 mg/ml). Furthermore, the truffle extracts were tested for their antibacterial activity against seven species of bacteria. The methanolic extract also exhibited remarkable inhibitory activity on the tested strains, which minimum inhibitory concentration values ranged from 0.25 to 1.3 mg/ml.

Journal of Essential Oil Bearing Plants, 2012

ABSTRACT The essential oils of Calligonum comosum subcultured at the South-Eastern of Tunisia (Bi... more ABSTRACT The essential oils of Calligonum comosum subcultured at the South-Eastern of Tunisia (Bir Lahmar and Ghordab locations) and collected at the flowering and the fructification stages, were obtained by hydrodistillation and were analyzed by GC-FID and GC-MS in order to discern the differences and similarities between the investigated essential oils of this species. Sixty seven compounds representing 88.6495.60 % of the total essential oil were identified. The comparison of the essential oil components between the two locations of the subcultured C. comosum shows that there are 3 major common components identified at the two stages which were lauric acid, myristic acid and palmitic acid. Essential oil chemotype of C. comosum cultivated at Bir Lahmar location seems original since linoleic acid, palmitic and lauric acid were the most abundant compounds. While another new chemotype was evidenced from Ghordab location characterized by the dominance of linalool at the fructification stage and pentacosane at the flowering stage.

Analytical Sciences: X-ray Structure Analysis Online, 2008

Antioxidants, 2013

We aim to highlight the differential antioxidant status of Limoniastrum guyonianum and Limoniastr... more We aim to highlight the differential antioxidant status of Limoniastrum guyonianum and Limoniastrum monopetalum in relation to their respective chemical and location characteristics. Metabolite analysis revealed similar contents in phenolic, flavonoï ds, sugars and chlorophyll in the two species' leaves. Higher amounts of proline (Pro), carotenoï ds (Carot), sodium (Na) and potassium (K) were measured in L. monopetalum leaves relative to L. guyonianum ones. While the two Limoniastrum species have similar free radical DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity, L. guyonianum showed more than twofold higher ferrous ions chelating activity relative to L. monopetalum. However, highest reducing power activity was observed in L. monopetalum. Thiobarbituric acid-reactive substances (TBARS) determination indicated that L. monopetalum behave better lipid membrane integrity relative to L. guyonianum. These findings suggested that the lesser stressful state of L. monopetalum was related to higher metabolites accumulation and reducing capacity compared to L. guyonianum.

Journal of Chemistry, 2013

The present study describes chemical composition as well as cytotoxic, antioxidant, and antimicro... more The present study describes chemical composition as well as cytotoxic, antioxidant, and antimicrobial activities of winter savorySatureja montanaL. essential oil (EO). The plant was collected from south France mountain, and its EO was extracted by hydrodistillation (HD) and analysed by gas chromatography/mass spectrometry (GC/MS). Thirty-two compounds were identified accounting for 99.85% of the total oil, where oxygenated monoterpenes constituted the main chemical class (59.11%). The oil was dominated by carvacrol (53.35%),γ-terpinene (13.54%), and the monoterpenic hydrocarbonsp-cymene (13.03%). Moreover,S. montanaL. EO exhibited high antibacterial activities with strong effectiveness against several pathogenic food isolatedSalmonellaspp. includingS. enteritidiswith a diameter of inhibition zones growth ranging from 21 to 51 mm and MIC and MBC values ranging from 0.39–1.56 mg/mL to 0.39–3.12 mg/mL, respectively. Furthermore, theS. montanaL. EO was investigated for its cytotoxic and...

Natural Science, 2013

The essential oil composition of Thymus vulgaris L. and Rosmarinus officinalis L. endemic to Fran... more The essential oil composition of Thymus vulgaris L. and Rosmarinus officinalis L. endemic to France were determined by GC and GC-MS. Oils were assessed for their cytotoxic, antioxidant and antimicrobial activity. 31 and 37 different compounds were identified representing 99.64% and 99.38% of the thyme and rosemary oils respectively, where oxygenated monoterpenes constituted the main chemical class. Thymol (41.33%) and 1.8-cineole (24.10%) were identified as the main constituents of T. vulgaris L. and R. officinalis L., respectively. Essential oils (EOs) of selected plant species were evaluated for their in vitro cytotoxicity against the human lung adenocarcinoma epithelial cell line (A549). Cytotoxicity was measured using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphynyltetra-zolium bromide] colorimetric assay. Dose-dependent studies revealed IC50 of 8.50 ± 0.01 μg/mL and 10.50 ± 0.01 μg/mL after 72 h on the A549 cells for R. officinalis L. and T. vulgaris L., respectively. Antioxidant activity was determined using a quantitative DPPH (1,1-diphenyl- 2-picryl hydrazyl) assay. Thymus and rosemary EOs exhibited effective radical scavenging capacity with 50% inhibitory concentration (IC50) of 437 ± 5.46 μg/mL and 189 ± 2.38 μg/mL respectively and therefore acts as a natural antioxidant agent. The antimicrobial activity of these species has also been studied against several foodborne pathogens and food isolated Salmonella spp. including S. enteritidis of significant importance. According to the results, T. vulgaris L. showed higher bactericidal effect than those from R. officinalis L. These results suggest that the essential oil from T. vulgaris L. and R. officinalis L. have potential to be used as a natural cytotoxic, antioxidant and antimicrobial agent in food processing.

Zeitschrift für Naturforschung C, 2011

The essential oils obtained by hydrodistillation (Clevenger apparatus) from aerial parts of Astra... more The essential oils obtained by hydrodistillation (Clevenger apparatus) from aerial parts of Astragalus gombiformis were analysed by gas chromatography coupled with mass spectrometry (GC/MS). This study showed that the A. gombiformis essential oils are complex mixtures of important natural compounds, which varied qualitatively and quantitatively between cultivated and wild plants and between phenological stages of development. All analysed oils are characterized by the constant presence of phytol, 6,10,14-trimethyl-2-pentadecanone, 4-terpineol, and γ-terpinene. This study is the fi rst report on the chemical composition of essential oils from A. gombiformis and indicates that these oils should be more studied.