Faouzi Attia - Academia.edu (original) (raw)

Papers by Faouzi Attia

Research paper thumbnail of Agronomic application of olive mill wastewaters with rock phosphate increase the 10Me18:0 fatty acid marker of actinomycetes and change rhizosphere microbial functional groups under long-term field conditions

Soil Biology and Biochemistry, 2014

ABSTRACT

Research paper thumbnail of Pomegranate (Punicagranatum) Juices: Chemical Composition, Micronutrient Cations, and Antioxidant Capacity

Journal of Food Science, 2011

Phenolics, flavonoids, anthocyanins, and tannins of pomegranate juices, obtained from 9 Tunisian ... more Phenolics, flavonoids, anthocyanins, and tannins of pomegranate juices, obtained from 9 Tunisian ecotypes were quantified. Phenolics and flavonoids in the variety Tounsi (TN) (3299 mg gallic acid equivalents [GAE]/L and 636 mg quercetin equivalents [QE]/L of juice, respectively) were higher than in the variety Gabsi (GB) (1570 mg GAE/L and 135 mg QE/L of juice, respectively). The highest anthocyanins quantity was found in GB 2 with 156 mg cyanidin-3-glucoside equivalents (CGE)/L. TN 3 ecotype showed the highest tannins quantity with 2550 mg catechin equivalents (CE)/L of juice. TN 1 presented the highest radical-scavenging activity (2, 2'-azinobis-3-ethylbenzothiazoline-6-sulphonate [ABTS], IC₅₀ [50% inhibition concentration] = 525 mg/L), as well as the highest concentration of micronutrient cations (potassium and sodium). A high correlation (R² = 0.80) between antioxidant capacity and proanthocyanin contents was found, this suggests that proanthocyanins are the principal contributor in the antioxidant capacity of pomegranate. Our data suggest also that the high concentrations of K⁺ and Na⁺ may play a role in the adaptation of pomegranate to arid environments.

Research paper thumbnail of Accumulation of flavonoids and phenolic compounds in olive tree roots in response to mycorrhizal colonization: A possible mechanism for regulation of defense molecules

Journal of plant physiology, Jan 31, 2015

The arbuscular mycorrhizal (AM) fungus promotes plant growth and can alter the production of prim... more The arbuscular mycorrhizal (AM) fungus promotes plant growth and can alter the production of primary and secondary metabolites. The aim of this work was to determine the influence of AM fungi colonization on the content of phenolic compounds, flavonoids and soluble carbohydrates in olive (Olea europaea L.) tree roots. The results revealed that mycorrhizal plants had a higher content of flavonoids and total phenols. Analysis of sugar contents showed enhanced levels of sucrose and fructose in mycorrhizal roots, while glucose amounts stayed constant. The DPPH radical-scavenging activity of the mycorrhizal root methanolic extracts was higher than that of the non- mycorrhizal root methanolic extracts. These results indicated that olive tree roots contain significant amounts of phenolic compounds, important factors for antioxidant capacity, which can be substantially modified by colonization of olive trees with AM fungi.

Research paper thumbnail of Changes in the profiles of mineral elements, phenols, tocopherols and soluble carbohydrates of olive fruit following foliar nutrient fertilization

LWT - Food Science and Technology, 2014

ABSTRACT

Research paper thumbnail of Foliar treatments with Gaultheria procumbens essential oil induce defense responses and resistance against a fungal pathogen in Arabidopsis

Frontiers in Plant Science, 2014

Essential oil from Gaultheria procumbens is mainly composed of methylsalicylate (MeSA) (&... more Essential oil from Gaultheria procumbens is mainly composed of methylsalicylate (MeSA) (>96%), a compound which can be metabolized in plant tissues to salicylic acid, a phytohormone inducing plant immunity against microbial pathogens. The potential use of G. procumbens essential oil as a biocontrol agent was evaluated on the model plant Arabidopsis thaliana. Expression of a selection of defense genes was detected 1, 6, and 24 h after essential oil treatment (0.1 ml/L) using a high-throughput qPCR-based microfluidic technology. Control treatments included methyl jasmonate and a commercialized salicylic acid (SA) analog, benzo(1,2,3)-thiadiazole-7carbothiolic acid (BTH). Strong induction of defense markers known to be regulated by the SA pathway was observed after the treatment with G. procumbens essential oil. Treatment induced the accumulation of total SA in the wild-type Arabidopsis line Col-0 and analysis of the Arabidopsis line sid2, mutated in a SA biosynthetic gene, revealed that approximately 30% of MeSA sprayed on the leaves penetrated inside plant tissues and was demethylated by endogenous esterases. Induction of plant resistance by G. procumbens essential oil was tested following inoculation with a GFP-expressing strain of the Arabidopsis fungal pathogen Colletotrichum higginsianum. Fluorescence measurement of infected tissues revealed that treatments led to a strong reduction (60%) of pathogen development and that the efficacy of the G. procumbens essential oil was similar to the commercial product BION(®). Together, these results show that the G. procubens essential oil is a natural source of MeSA which can be formulated to develop new biocontrol products.

Research paper thumbnail of Effect of nutrient-based fertilisers of olive trees on olive oil quality

Journal of the Science of Food and Agriculture, 2013

This work was conducted to determine the effects of two nutrient-based fertilisers on the general... more This work was conducted to determine the effects of two nutrient-based fertilisers on the general physicochemical characteristics (including free fatty acid content, peroxide value and UV spectrophotometric characteristics), fatty acid profile, total phenols, o-diphenols and phytosterol composition of olive oil. Foliar applications were carried out in two successive years and included four treatments: TC (control, without foliar nutrition), T1 (rich in nitrogen, applied at the start of vegetation, 10 days later and 20 days later), T2 (rich in boron, magnesium, sulfur and manganese, applied at the beginning of flowering and 10 days later) and T3 (T1+T2). At the end of the experiment (after 2 years), oils were extracted and analysed. No effect was found on either general physicochemical characteristics or fatty acid composition. Foliar fertilisation caused a significant decrease in both polyphenol and o-diphenol contents. Total sterol content was unaffected by foliar fertilisation. However, the phytosterol composition of the oil, particularly its β-sitosterol level, was markedly improved after foliar nutrient application. Principal component analysis of the phytosterol composition showed discrimination between the control oil and the oils from T1, T2 and T3 treatments. The results of this study extend the current knowledge of such cross-talk between plant nutrition and quality of oil.

Research paper thumbnail of Colonisation of olive trees (Olea europaea L.) with the arbuscular mycorrhizal fungus Glomus sp modified the glycolipids biosynthesis and resulted in accumulation of unsaturated fatty acids

Journal of Plant Physiology, 2014

The influence of arbuscular mycorrhizal (AM) fungi colonization on photosynthesis, mineral nutrit... more The influence of arbuscular mycorrhizal (AM) fungi colonization on photosynthesis, mineral nutrition, the amount of phospholipids and glycolipids in the leaves of olive (Olea europaea L.) trees was investigated. After six months of growth, the rate of photosynthesis, carboxylation efficiency, transpiration and stomatal conductance in mycorrhizal (M) plants was significantly higher than that of non-mycorrhizal (NM) plants. The inoculation treatment increased the foliar P and Mg but not N. The amount of glycolipids in the leaves of M plants was significantly higher than that of NM plants. However, the amount of phospholipids in the leaves of M plants was not significantly different to that in the leaves of NM plants. Also, we observed a significant increase in the level of α-linolenic acid (C18:3ω3) in glycolipids of M plants. This work supports the view that increased glycolipids level in the leaves of M plants could be involved, at least in part, in the beneficial effects of mycorrhizal colonization on photosynthesis performance of olive trees. To our knowledge, this is the first report on the effect of AM fungi on the amount of glycolipids in the leaves of mycorrhizal plants.

Research paper thumbnail of Agronomic application of olive mill wastewaters with phosphate rock in a semi-arid Mediterranean soil modifies the soil properties and decreases the extractable soil phosphorus

Journal of Environmental Management, 2007

Research paper thumbnail of Enhancement of Antioxidants in Olive Oil by Foliar Fertilization of Olive Trees

Journal of the American Oil Chemists' Society, 2013

ABSTRACT

Research paper thumbnail of Effects of agronomic application of olive mill wastewater in a field of olive trees on carbohydrate profiles, chlorophyll a fluorescence and mineral nutrient content

Environmental and Experimental Botany, 2011

Research paper thumbnail of Effet du déficit hydrique au niveau de la phase photochimique du PSII chez deux variétés d'olivier

Comptes Rendus Biologies, 2006

Research paper thumbnail of Changes in microbial communities and carbohydrate profiles induced by the mycorrhizal fungus (Glomus intraradices) in rhizosphere of olive trees (Olea europaea L.)

ABSTRACT The influence of inoculation of olive trees with arbuscular mycorrhizal (AM) fungi, Glom... more ABSTRACT The influence of inoculation of olive trees with arbuscular mycorrhizal (AM) fungi, Glomus (G) intraradices, on microbial communities and sugar concentrations, were examined in rhizosphere of olive trees (Olea europaea L.). Analyses of phospholipid and neutral lipid fatty acids (PLFA and NLFA, respectively) were then used to detect changes in microbial community structure in response to inoculation of plantlets with G. intraradices. Microscopic observations studies revealed that the extraradical mycelium of the fungus showed formation of branched absorbing structures (BAS) in rhizosphere of olive tree. Root colonization with the AM fungi G. intraradices induced significant changes in the bacterial community structure of olive tree rhizosphere compared to non-mycorrhizal plants. The largest proportional increase was found for the fatty acid 10Me18:0, which indicated an increase in the number of actinomycetes in mycorrhizal rhizosphere soil, whereas the PLFAs i15:0, a15:0, i16:0, 16:1ω7 and cy17:0 which were used as indicators of bacteria decreased in mycorrhizal treatment compared to non-mycorrhizal control treatment. A highest concentration of glucose and trehalose and a lowest concentration of fructose, galactose, sucrose, raffinose and mannitol were detected in mycorrhizal rhizosphere soil. This mycorrhizal effect on rhizosphere communities may be a consequence of changes in characteristics in the environment close to mycorrhizal roots.

Research paper thumbnail of Olive mill wastewater effects on the microbial communities as studied in the field of olive trees by analysis of fatty acid signatures

European Journal of Soil Biology, 2010

Research paper thumbnail of Agronomic application of olive mill wastewaters with rock phosphate increase the 10Me18:0 fatty acid marker of actinomycetes and change rhizosphere microbial functional groups under long-term field conditions

Soil Biology and Biochemistry, 2014

ABSTRACT

Research paper thumbnail of Pomegranate (Punicagranatum) Juices: Chemical Composition, Micronutrient Cations, and Antioxidant Capacity

Journal of Food Science, 2011

Phenolics, flavonoids, anthocyanins, and tannins of pomegranate juices, obtained from 9 Tunisian ... more Phenolics, flavonoids, anthocyanins, and tannins of pomegranate juices, obtained from 9 Tunisian ecotypes were quantified. Phenolics and flavonoids in the variety Tounsi (TN) (3299 mg gallic acid equivalents [GAE]/L and 636 mg quercetin equivalents [QE]/L of juice, respectively) were higher than in the variety Gabsi (GB) (1570 mg GAE/L and 135 mg QE/L of juice, respectively). The highest anthocyanins quantity was found in GB 2 with 156 mg cyanidin-3-glucoside equivalents (CGE)/L. TN 3 ecotype showed the highest tannins quantity with 2550 mg catechin equivalents (CE)/L of juice. TN 1 presented the highest radical-scavenging activity (2, 2'-azinobis-3-ethylbenzothiazoline-6-sulphonate [ABTS], IC₅₀ [50% inhibition concentration] = 525 mg/L), as well as the highest concentration of micronutrient cations (potassium and sodium). A high correlation (R² = 0.80) between antioxidant capacity and proanthocyanin contents was found, this suggests that proanthocyanins are the principal contributor in the antioxidant capacity of pomegranate. Our data suggest also that the high concentrations of K⁺ and Na⁺ may play a role in the adaptation of pomegranate to arid environments.

Research paper thumbnail of Accumulation of flavonoids and phenolic compounds in olive tree roots in response to mycorrhizal colonization: A possible mechanism for regulation of defense molecules

Journal of plant physiology, Jan 31, 2015

The arbuscular mycorrhizal (AM) fungus promotes plant growth and can alter the production of prim... more The arbuscular mycorrhizal (AM) fungus promotes plant growth and can alter the production of primary and secondary metabolites. The aim of this work was to determine the influence of AM fungi colonization on the content of phenolic compounds, flavonoids and soluble carbohydrates in olive (Olea europaea L.) tree roots. The results revealed that mycorrhizal plants had a higher content of flavonoids and total phenols. Analysis of sugar contents showed enhanced levels of sucrose and fructose in mycorrhizal roots, while glucose amounts stayed constant. The DPPH radical-scavenging activity of the mycorrhizal root methanolic extracts was higher than that of the non- mycorrhizal root methanolic extracts. These results indicated that olive tree roots contain significant amounts of phenolic compounds, important factors for antioxidant capacity, which can be substantially modified by colonization of olive trees with AM fungi.

Research paper thumbnail of Changes in the profiles of mineral elements, phenols, tocopherols and soluble carbohydrates of olive fruit following foliar nutrient fertilization

LWT - Food Science and Technology, 2014

ABSTRACT

Research paper thumbnail of Foliar treatments with Gaultheria procumbens essential oil induce defense responses and resistance against a fungal pathogen in Arabidopsis

Frontiers in Plant Science, 2014

Essential oil from Gaultheria procumbens is mainly composed of methylsalicylate (MeSA) (&... more Essential oil from Gaultheria procumbens is mainly composed of methylsalicylate (MeSA) (>96%), a compound which can be metabolized in plant tissues to salicylic acid, a phytohormone inducing plant immunity against microbial pathogens. The potential use of G. procumbens essential oil as a biocontrol agent was evaluated on the model plant Arabidopsis thaliana. Expression of a selection of defense genes was detected 1, 6, and 24 h after essential oil treatment (0.1 ml/L) using a high-throughput qPCR-based microfluidic technology. Control treatments included methyl jasmonate and a commercialized salicylic acid (SA) analog, benzo(1,2,3)-thiadiazole-7carbothiolic acid (BTH). Strong induction of defense markers known to be regulated by the SA pathway was observed after the treatment with G. procumbens essential oil. Treatment induced the accumulation of total SA in the wild-type Arabidopsis line Col-0 and analysis of the Arabidopsis line sid2, mutated in a SA biosynthetic gene, revealed that approximately 30% of MeSA sprayed on the leaves penetrated inside plant tissues and was demethylated by endogenous esterases. Induction of plant resistance by G. procumbens essential oil was tested following inoculation with a GFP-expressing strain of the Arabidopsis fungal pathogen Colletotrichum higginsianum. Fluorescence measurement of infected tissues revealed that treatments led to a strong reduction (60%) of pathogen development and that the efficacy of the G. procumbens essential oil was similar to the commercial product BION(®). Together, these results show that the G. procubens essential oil is a natural source of MeSA which can be formulated to develop new biocontrol products.

Research paper thumbnail of Effect of nutrient-based fertilisers of olive trees on olive oil quality

Journal of the Science of Food and Agriculture, 2013

This work was conducted to determine the effects of two nutrient-based fertilisers on the general... more This work was conducted to determine the effects of two nutrient-based fertilisers on the general physicochemical characteristics (including free fatty acid content, peroxide value and UV spectrophotometric characteristics), fatty acid profile, total phenols, o-diphenols and phytosterol composition of olive oil. Foliar applications were carried out in two successive years and included four treatments: TC (control, without foliar nutrition), T1 (rich in nitrogen, applied at the start of vegetation, 10 days later and 20 days later), T2 (rich in boron, magnesium, sulfur and manganese, applied at the beginning of flowering and 10 days later) and T3 (T1+T2). At the end of the experiment (after 2 years), oils were extracted and analysed. No effect was found on either general physicochemical characteristics or fatty acid composition. Foliar fertilisation caused a significant decrease in both polyphenol and o-diphenol contents. Total sterol content was unaffected by foliar fertilisation. However, the phytosterol composition of the oil, particularly its β-sitosterol level, was markedly improved after foliar nutrient application. Principal component analysis of the phytosterol composition showed discrimination between the control oil and the oils from T1, T2 and T3 treatments. The results of this study extend the current knowledge of such cross-talk between plant nutrition and quality of oil.

Research paper thumbnail of Colonisation of olive trees (Olea europaea L.) with the arbuscular mycorrhizal fungus Glomus sp modified the glycolipids biosynthesis and resulted in accumulation of unsaturated fatty acids

Journal of Plant Physiology, 2014

The influence of arbuscular mycorrhizal (AM) fungi colonization on photosynthesis, mineral nutrit... more The influence of arbuscular mycorrhizal (AM) fungi colonization on photosynthesis, mineral nutrition, the amount of phospholipids and glycolipids in the leaves of olive (Olea europaea L.) trees was investigated. After six months of growth, the rate of photosynthesis, carboxylation efficiency, transpiration and stomatal conductance in mycorrhizal (M) plants was significantly higher than that of non-mycorrhizal (NM) plants. The inoculation treatment increased the foliar P and Mg but not N. The amount of glycolipids in the leaves of M plants was significantly higher than that of NM plants. However, the amount of phospholipids in the leaves of M plants was not significantly different to that in the leaves of NM plants. Also, we observed a significant increase in the level of α-linolenic acid (C18:3ω3) in glycolipids of M plants. This work supports the view that increased glycolipids level in the leaves of M plants could be involved, at least in part, in the beneficial effects of mycorrhizal colonization on photosynthesis performance of olive trees. To our knowledge, this is the first report on the effect of AM fungi on the amount of glycolipids in the leaves of mycorrhizal plants.

Research paper thumbnail of Agronomic application of olive mill wastewaters with phosphate rock in a semi-arid Mediterranean soil modifies the soil properties and decreases the extractable soil phosphorus

Journal of Environmental Management, 2007

Research paper thumbnail of Enhancement of Antioxidants in Olive Oil by Foliar Fertilization of Olive Trees

Journal of the American Oil Chemists' Society, 2013

ABSTRACT

Research paper thumbnail of Effects of agronomic application of olive mill wastewater in a field of olive trees on carbohydrate profiles, chlorophyll a fluorescence and mineral nutrient content

Environmental and Experimental Botany, 2011

Research paper thumbnail of Effet du déficit hydrique au niveau de la phase photochimique du PSII chez deux variétés d'olivier

Comptes Rendus Biologies, 2006

Research paper thumbnail of Changes in microbial communities and carbohydrate profiles induced by the mycorrhizal fungus (Glomus intraradices) in rhizosphere of olive trees (Olea europaea L.)

ABSTRACT The influence of inoculation of olive trees with arbuscular mycorrhizal (AM) fungi, Glom... more ABSTRACT The influence of inoculation of olive trees with arbuscular mycorrhizal (AM) fungi, Glomus (G) intraradices, on microbial communities and sugar concentrations, were examined in rhizosphere of olive trees (Olea europaea L.). Analyses of phospholipid and neutral lipid fatty acids (PLFA and NLFA, respectively) were then used to detect changes in microbial community structure in response to inoculation of plantlets with G. intraradices. Microscopic observations studies revealed that the extraradical mycelium of the fungus showed formation of branched absorbing structures (BAS) in rhizosphere of olive tree. Root colonization with the AM fungi G. intraradices induced significant changes in the bacterial community structure of olive tree rhizosphere compared to non-mycorrhizal plants. The largest proportional increase was found for the fatty acid 10Me18:0, which indicated an increase in the number of actinomycetes in mycorrhizal rhizosphere soil, whereas the PLFAs i15:0, a15:0, i16:0, 16:1ω7 and cy17:0 which were used as indicators of bacteria decreased in mycorrhizal treatment compared to non-mycorrhizal control treatment. A highest concentration of glucose and trehalose and a lowest concentration of fructose, galactose, sucrose, raffinose and mannitol were detected in mycorrhizal rhizosphere soil. This mycorrhizal effect on rhizosphere communities may be a consequence of changes in characteristics in the environment close to mycorrhizal roots.

Research paper thumbnail of Olive mill wastewater effects on the microbial communities as studied in the field of olive trees by analysis of fatty acid signatures

European Journal of Soil Biology, 2010