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Ammar I.,University of Sfax | BenAmira A.,University of Sfax | Khemakem I.,University of Sfax | Attia H.,University of Sfax | And 2 more authors.
Journal of Food Science and Technology | Year: 2017

This study was focused on the evaluation of the quality and the oxidative stability of olive oil added with Opuntia ficus-indica flowers. Two different amounts of O. ficus-indica flowers were considered 5 and 15% (w/w). The olive oils were evaluated towards their quality, fatty acids profile, total phenol contents and thermal properties by differential scanning calorimetry. The oxidative stability was also monitored by employing the Rancimat and the oven test based on accelerating the oxidation process during storage. The addition of O. ficus-indica flowers induced an increase in free acidity values and a variation in fatty acids profile of olive oils but values remained under the limits required for an extra-virgin olive oil. The obtained olive oils were nutritionally enriched due to the increase in their phenols content. The oxidative stability was generally improved, mainly in olive oil enriched with 5% Opuntia ficus-indica flowers. These findings proved that this enriched olive oil could be considered as a product with a greater added value. © 2017 Association of Food Scientists & Technologists (India)


Ammar I.,University of Sfax | Ennouri M.,University of Sfax | Ennouri M.,Higher Institute of Applied science and Technology of Mahdia | Bali O.,University of Sfax | Attia H.,University of Sfax
LWT - Food Science and Technology | Year: 2014

Opuntia flowers belonging to two species of prickly pear were evaluated at four flowering stages: vegetative, initial flowering, full flowering and post-flowering stage, for possible use as a potential source in the food enrichment. Chemical composition including moisture, ash, protein, fat, soluble sugars, total fibers, mineral amounts and fatty acid profiles of Opuntia ficus-indica and Opuntia stricta flowers were investigated. Functional properties (swelling capacity (SWC), water holding capacity (WHC), water solubility index (WSI) and oil holding capacity (OHC)) were also studied. Results showed that during the maturation of flowers, there is a decrease in protein contents whereas fat contents increase, for both species. High minerals amounts were noticed in Opuntia flowers and they can be considered as an excellent source of minerals. The fatty acids profiles were dominated by the palmitic acid (38-59%). The techno-functional properties (SWC, WSI, WHC and OHC) were found to be important and they can be modulated according to the temperatures. Owing to its chemical profile and functional properties, Opuntia flowers could be used as an ingredient to improve different physical and nutritional properties of foods. © 2014 Elsevier Ltd.


Ennouri M.,Higher Institute of Applied science and Technology of Mahdia | Ennouri M.,Alimentary Analysis Unit | Khemakhem B.,University of Sfax | Hassen H.B.,University of Sfax | And 4 more authors.
Journal of the Science of Food and Agriculture | Year: 2013

Background: In Tunisia, prickly pear fruit grow spontaneously; it is consumed as fresh fruit, juice or jam. When the fruit is used for juice production, the seeds are discarded and go to waste. Our study aimed to extract biomolecules from seeds by producing value-added products from the fruits. Results: An amylase from Opuntia ficus-indica seeds was extracted and purified to homogeneity. An increase in specific activity of 113-fold was observed. The apparent molecular mass of the enzyme is 64 kDa. The optimum pH and temperature for enzyme activity were pH 5 and 60 ?C, respectively. Under these conditions, the specific activity is 245.5 U mg-1. The enzyme was activated by Co2+ and Mg2+ (relative activity 117% and 113% respectively) at lower ion concentrations. It was strongly inhibited byMn2+ and Fe2+. Cu2+ inhibited totally the activity of this enzyme, but Ca2+ has an inhibitory effect which increases with ion concentration. Conclusion:The extractedenzymebelongs to the exo type of amylasesandis classified as aβ-cyclodextringlycosyltransferase since it generates mainly β-cyclodextrin from starch. It exhibits high thermal stability and a broad range of pH stability, making it a promising prospect for industrial and food applications. © 2012 Society of Chemical Industry.


Ennouri M.,Higher Institute of Applied science and Technology of Mahdia | Ennouri M.,Alimentary Analysis Unit | Ammar I.,Alimentary Analysis Unit | Khemakhem B.,University of Sfax | Attia H.,Alimentary Analysis Unit
Journal of Medicinal Food | Year: 2014

Opuntia ficus-indica f. inermis (cactus pear) flowers have wide application in folk medicine. However, there are few reports focusing on their biological activity and were no reports on their chemical composition. The nutrient composition and hexane extracts of Opuntia flowers at 4 flowering stages and their antibacterial and antifungal activities were investigated. The chemical composition showed considerable amounts of fiber, protein, and minerals. Potassium (K) was the predominant mineral followed by calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), and zinc (Zn). The main compounds in the various hexane extracts were 9.12-octadecadienoic acid (29-44%) and hexadecanoic acid (8.6-32%). The antibacterial activity tests showed that O. inermis hexane extracts have high effectiveness against Escherichia coli and Staphylococcus aureus, making this botanical source a potential contender as a food preservative or food control additive. © 2014, Mary Ann Liebert, Inc. and Korean Society of Food Science and Nutrition.


Ammar I.,Alimentary Analysis Unit | Ennouri M.,Alimentary Analysis Unit | Ennouri M.,Higher Institute of Applied science and Technology of Mahdia | Khemakhem B.,University of Sfax | Attia H.,Alimentary Analysis Unit
Industrial Crops and Products | Year: 2012

The chemical composition of hexane extracts from flowers belonging to two species of prickly pear, Opuntia ficus-indica (L.) Miller and Opuntia stricta (Haw.) Haworth has been studied by gas chromatography-mass spectrometry in four developmental stages of flower: vegetative, initial flowering, full flowering, and post-flowering stages. Remarkable differences were noted between the flowers' compositions. The main compounds were carboxylic acid (28-97%), terpenes (0.2-57%), esters (0.2-27%), and alcohols (<1.8%).The study of the biological activities showed that extracts were active in vitro towards four bacteria and two fungal strains. It exhibited remarkable activity against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli.Antioxidant activity of the flowers extracts was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method.Our findings demonstrate the interest of Opuntia flowers extract as a source of bioactive substances and its potential preservative use in food. © 2011 Elsevier B.V.


Salem F.,National Institute of Science and Technology of the Sea | Afef N.,University of Monastir | Ben Ouada H.,University of Monastir | Ben Mansour H.,University of Monastir | Ben Mansour H.,Higher Institute of Applied science and Technology of Mahdia
Bioremediation Journal | Year: 2015

Industrialization is a boon for developing countries such as Tunisia. However, textile effluents that are being discharged are environmental pollutants, extremely toxic to plants and other living organisms, including humans. The current study was conducted to determine the phytotoxic effect of textile effluents, collected near an industrial zone in the center of Tunisia (Ksar Helal), on the germination and various growth indices of durum wheat (Triticumaestivum L.). Results showed that textile effluent treatments reduced significantly the percentage of seed germination and slowed its kinetic as compared with control. Roots and leaves were also significantly reduced. The phytotoxicity was highly reduced from textile effluents after aerobic biotreatment with bacteria. It can be concluded that the biological treatment process of textile wastewater might serve as a fertilizer production that is able to improve the growth of plants. These results are encouraging in the context of developing a low-budget technology for the effective management of these effluents. © 2015 © 2015 Taylor & Francis Group, LLC.


Baccouche A.,Alimentary Analysis Unit | Ennouri M.,Alimentary Analysis Unit | Ennouri M.,Higher Institute of Applied science and Technology of Mahdia | Felfoul I.,Alimentary Analysis Unit | Attia H.,Alimentary Analysis Unit
Food Hydrocolloids | Year: 2013

This study aimed at the development of whey-based prickly pear (WBP) beverages. Prickly pear juice and acid whey were characterized and a factorial design was used to study the effect of three factors. Four formulations of whey-based prickly pear beverages were prepared using the fractional 23-1 factorial design. To note, the three factors considered were whey treatment (WT) and added sugar and pectin (Sand P). Two levels for each factor were tested, namely added sugar (5 or 10%), whey treatment (with or without heat treatment) and added pectin (0 or 0.05%). The turbidity percentage increase, the color-index percentage decrease, the sedimentation percentage increase, as well as the serum separation percentage were evaluated after 40 days of storage condition at 4°C. The three factors optimization for the beverages' maximum stability were implemented by testing the main and interaction effects plots, the analysis of variance (ANOVA), the normal probability plots of standardized effects and residuals, the Pareto charts and the contour plots. The achieved results showed that the beverages were physically stabilized by sugar and HM-pectin amount increase using the heat-treated whey. Hence, regression models were suggested, which fitted the experimental data very well (R2 >75% and p<0.05). © 2013 Elsevier Ltd.


Guitouni Z.,Higher Institute of Applied science and Technology of Mahdia | Guitouni Z.,University of Monastir | Chotin-Avot R.,University Paris - Sud | Machhout M.,University of Monastir | And 2 more authors.
5th Conference on Design and Technology of Integrated Systems in Nanoscale Era, DTIS 2010 | Year: 2010

Cellular automata (CA) have been accepted as a good evolutionary computational model for the simulation of complex physical systems. They have been used for various applications, such as parallel processing computations and number theory. In this paper, we studied the applications of cellular automata for the modular multiplications; we proposed two new architectures of multipliers based on cellular automata over finite field GF(2m). Since they have regularity, modularity and concurrency, they are suitable for VLSI implementation. The proposed architectures can be easily implemented into the hardware design of crypto-coprocessors. © 2010 IEEE.


Ammar I.,Alimentary Analysis Unit | Ennouri M.,Alimentary Analysis Unit | Ennouri M.,Higher Institute of Applied science and Technology of Mahdia | Attia H.,Alimentary Analysis Unit
Industrial Crops and Products | Year: 2015

The effect of different extracting solvents used by two methods on the total polyphenols and flavonoids contents of Opuntia ficus-indica flowers was studied. The antioxidant activity of these extracts was investigated by using DPPH radical scavenging, reducing power and β-carotene bleaching assays. The results showed that extracts exhibited different levels of polyphenols contents and antioxidant activity. Thus, solvents with different polarities had significant effect on antioxidant activity. The methanolic and aqueous extracts proved best in terms of high extraction of phenolic compounds and antioxidant activity. Moreover, it can be concluded that extracts obtained by Soxhlet method were the most interesting in terms of antioxidant activity and proved that polyphenols responsible for the antioxidant activity of O. ficus-indica flowers are thermostable. These results showed that O. ficus-indica flowers could be a potential natural source of antioxidants that can be used in food and nutraceutical applications. © 2014 Elsevier B.V.

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