Sonda Ammar

New insights into the qualitative phenolic profile of Ficus carica L. fruits and leaves from Tunisia using ultra-high-performance liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry and their antioxidant activity

Ficus carica L. fruits have been consumed from the earliest times, and other parts of the tree have been used for traditional medicinal purposes. Nowadays, the beneficial properties of this and other Ficus species are attributed to the presence of key phytochemicals. To increase our knowledge about this topic, the present study has conducted phenolic profiling of the leaves and whole fruits from two Tunisian cultivars, ‘Temri’ and ‘Tounsi’, using reversed-phase ultra-high-performance liquid chromatography (RP-UHPLC) coupled to two detection systems: diode-array detection (DAD) and quadrupole time-of-flight (QTOF) mass spectrometry (MS). UV-Vis absorption was a valuable tool for classifying phenolic compounds into families, while MS using electrospray ionization (ESI) and MS/MS allowed the molecular formula to be established and structural information to be obtained. The total phenol content and the antioxidant activity were also assessed. As a result, in the negative ionization mode 91 phenolic compounds were characterized including hydroxybenzoic acids, hydroxycinnamic acids, hydroxycoumarins and flavanoids (flavonols, flavones, flavanones, flavanonols, flavanols and isoflavones). This work was complemented by the detection of other 18 phenolic compounds in the positive ionization mode, including anthocyanins and furanocoumarins. To the best of our knowledge, this is the first time most of these compounds have been tentatively reported in F. carica. These results indicate the complexity of this family of secondary metabolites in F. carica, as well as the potential of this analytical method for characterization purposes. In conclusion, the qualitative phenolic profile, total phenolic content and antioxidant activity differed especially between leaves and fruits.

Antihyperlipidemic and Antioxidant Activities of Edible Tunisian Ficus carica L. Fruits in High Fat Diet-Induced Hyperlipidemic Rats

The phenolic constituents of the aqueous-ethanolic extract of Tunisian Ficus carica (F. carica) fruit (FE) and its antihyperlipidemic and antioxidant activities in high-fat diet-induced hyperlipidemic rats (HFD) were evaluated. The obtained results demonstrated that the FE improved the lipid profile by decreasing the total cholesterol, triglyceride, low-density lipoprotein cholesterol and increasing high-density lipoprotein cholesterol levels. It also reduced the content of thiobarbituric acid-reactive substances and increased the antioxidant enzymes in liver, heart and kidney in HFD-fed rats. These antihyperlipidemic effects and in vivo antioxidative effects correlated with the in vitro phenolic content scavenging ability. Thus, the major phenolic compounds were identified using reversed-phase ultra-high-performance liquid chromatography (RP-UHPLC) coupled with two detection systems: diode-array detection (DAD) and quadrupole time-of-flight (QTOF) mass spectrometry (MS). Therefore, in the negative ionization mode, 28 phenolic compounds, including hydroxybenzoic acids, hydroxycinnamic acids, flavanoids and hydroxycoumarins were characterized. Dihydroxybenzoic acid di-pentoside, the flavonol quercetin 3-O-rutinoside and the flavone assigned as apigenin 8-C-glucoside were the main representative compounds in ‘Tounsi’ fruits. This work was complemented by the detection of seven other phenolic compounds in the positive ionization mode, including anthocyanins and furanocoumarins. Overall, these results have shown that the FE has a significant hypocholesterolemic effect and antioxidant activity in HFD-fed rats. This beneficial effect may be partly due to these phenolic constituents, especially vitexin, dihydroxybenzoic acid di-pentoside as well as rutin.

Urtica dioica attenuates ovalbumin-induced inflammation and lipid peroxidation of lung tissues in rat asthma model

Abstract Context: To find bioactive medicinal herbs exerting anti-asthmatic activity, we investigated the effect of an aqueous extract of Urtica dioica L. (Urticaceae) leaves (UD), the closest extract to the Algerian traditional use. Objective: In this study, we investigated the in vivo anti-asthmatic and antioxidant activities of nettle extract. Materials and methods: Adult male Wistar rats were divided into four groups: Group I: negative control; group II: Ovalbumin sensitized/challenged rats (positive control); group III: received UD extract (1.5 g/kg/day) orally along the experimental protocol; group IV: received UD extract (1.5 g/kg/day) orally along the experimental protocol and sensitized/challenged with ovalbumin. After 25 days, blood and tissue samples were collected for haematological and histopathological analysis, respectively. The oxidative stress parameters were evaluated in the lungs, liver and erythrocytes. Then, correlations between markers of airway inflammation and markers of oxidative stress were explored. Results: UD extract significantly (p < 0.01) inhibited eosinophilia increases in BALF (−60%) and the levels of leucocytes (−32.75%) and lymphocytes (−29.22%) in serum, and effectively suppressed inflammatory cells recruitment in the asthmatic rat model. Besides, the lipid peroxidation generated by allergen administration was significantly (p < 0.05) diminished by UD treatment in lung tissue (−48.58%). The nettle extract was also investigated for the total phenolic content (30.79 ± 0.96 mg gallic acid/g dry extract) and shows DPPH radical scavenging activity with 152.34 ± 0.37 μg/mL IC50 value. Conclusions: The results confirmed that UD administration might be responsible for the protective effects of this extract against airway inflammation.

LC–MS phenolic profiling combined with multivariate analysis as an approach for the characterization of extra virgin olive oils of four rare Tunisian cultivars during ripening

In this work, the phenolic composition of four rare cultivars grown under the same agronomical and environmental conditions was studied. This is to test the effects of cultivars and ripening index essentially on phenolic composition in olive oils as well as tocopherols composition, organoleptic profiling and oxidative properties. Furthermore, some agronomical traits were determined in which a general increase in the size of the fruit and oil contents were recorded for all cultivars. The phenolic fractions were identified and quantified using liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) in multiple reaction monitoring mode (MRM). A total of 13 phenolic compounds belonging to different chemical families were determined. Qualitative and quantitative differences in phenolic composition were observed among cultivars and also among sampling times. On the contrary to the agronomical traits, a general decrease (p<0.05) of total phenolic compounds was observed during maturation. Likewise, a decrease in tocopherols concentrations and oxidative properties was observed.

Comparison and characterization of volatile compounds as markers of oils stability during frying by HS–SPME-GC/MS and Chemometric analysis

The formation and emission of volatile compounds, including the aldehydes and some toxic compounds of oil samples, ROPO pure (100%) and the blended ROPO/RCO (80-20%), were carried out during deep frying at 180°C. The volatile profile of both oil samples was evaluated by an optimized HS-SPME-GC/MS method, before and after 20, 40 and 60 successive sessions of deep-frying. Actually, from 100 detected compounds, aldehydes were found to be the main group formed. In addition, the oil degradation under thermal treatment regarding the volatile compounds were evaluated and compared. Consequently, the blended ROPO/RCO revealed fewer formations of unsaturated aldehydes, including toxic ones, such as acrolein, and showed a greater stability against oxidative thermal degradation compared to ROPO pure.

RP-HPLC–DAD-ESI-TOF–MS based strategy for new insights into the qualitative and quantitative phenolic profile in Tunisian industrial Citrus Limon by-product and their antioxidant activity

Citrus by-products are an important source of bioactive constituents, such as organic acids and phenolic compounds, with health promoting and nutritive properties. To increase our knowledge about this topic, the aim of the present study was to undertake a comprehensive characterization and quantification of major bioactive compounds in Citrus limon by-product dried powder (CBP) proceeding from a Tunisian company using reversed-phase high performance liquid chromatography (RP-HPLC) coupled to electrospray ionization time-of-flight mass spectrometry (ESI-TOF–MS) operating in negative ion mode. Physicochemical properties and the antioxidant activity of CBP were also assessed. As a result, 38 phenolic compounds including 6 phenolic acid derivatives, and 32 flavonoids were characterized and quantified. This work was complemented by the detection of 2 organic acids. To the best of our knowledge, 6 phenolic compounds have not previously been recorded in CBP. In this regard, the main flavonoids in CBP were the flavanones hesperetin 7-O-rutinoside, eriodictyol 7-O-rutinoside, and hesperetin 7-O-neohesperidoside followed by the flavones diosmin. Moreover, the dimer of caffeic acid-O-hexoside was the major phenolic acid. In addition, these results suggested that the extract obtained from CBP had an interesting antioxidant activity comparable with synthetic antioxidants and showed also high amounts of dietary fiber, protein, total sugars, and carotenoids. Finally, the results obtained in this work confirmed that the CBP is a good source of bioactive compounds and the isolation of antioxidant nutraceuticals could be an advantageous way to revalorize these by-products for potential use as dietary additives in functional foods and cosmetics as well as in pharmaceutical industry.

HPLC-DAD-QTOF-MS profiling of phenolics from leaf extracts of two Tunisian fig cultivars: Potential as a functional food

The phenolic constituents of the aqueous-ethanolic extract of two Tunisian Ficus carica leaves cultivars and their hypoglycaemic, hypolipidaemic and antioxidative activities in alloxan-induced diabetic rats were investigated. Our results demonstrated that the treatment with the leaves extracts of F. carica improved lipid profile and reduced blood glucose level as well as thiobarbituric acid-reactive substances content. The antioxidant enzymes activity in the liver and heart tissues of diabetic rats was increased after the treatment. These antihyperglycaemic, antihyperlipidaemic and antioxidant effects of both leaf extracts could be associated with their in vitro scavenging ability and their phenolic composition. The HPLC-DAD-QTOF-MS analysis of both extracts revealed the presence of dihydroxybenzoic acid, dipentoside, rutin, psoralen, methoxypsoralen and oxypeudacin hydrate as relatively the most abundant compounds. These results showed indicated the capacity of the leaves extracts of F. carica to ameliorate hyperglycaemia, hyperlipidaemia and antioxidant status in diabetic rats.

Use of ultra-high-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry system as valuable tool for an untargeted metabolomic profiling of Rumex tunetanus flowers and stems and contribution to the antioxidant activity

&NA; Rumex tunetanus is an untapped resource with no available information about their chemical composition. That is why, the present study has conducted comprehensive metabolites profiling of the hydromethanol extracts of the Rumex tunetanus flowers and stems using RP‐UHPLC‐ESI‐QTOF‐MS. As results, 60 compounds were characterized for the first time in Rumex tunetanus between them, 18 photochemical were firstly identified in the Polygonaceae family in negative ionization mode. In this regard, quercetin‐3‐O‐glucuronide and (−)‐epicatechin gallate were the most abundant phenolic compounds in flowers and stems, respectively. Moreover, positive correlations were found between the antioxidant activity measured by DPPH and FRAP assays with the total phenolic compounds (r = 0.98; r = 0.99, respectively) and the abundance of some phenolic subfamilies such as hydroxycinnamic acids, hydroxybenzoic acids, flavonols and flavones with r > 0.86. The compounds displaying significant (P < 0.01) and good correlations with the antioxidant activity (r > 0.93) were hydroxybenzoic acid, rutin, quercetin‐3‐O‐glucuronide, quercetin‐3‐O‐glucoside, quercetin and luteolin‐7‐O‐rutinoside. In conclusion, Rumex tunetanus flowers and stems showed different bioactive compound profiles and significant antioxidant properties and could be further used in food and nutraceutical industries. Graphical abstract Figure. No caption available. HighlightsRP‐UHPLC–DAD‐ESI‐QTOF‐MS and MS/MS analysis of Hydromethanol extracts of Rumex tunetanus flowers and stems was performed.60 compounds from 12 families were tentatively identified for the first time in Rumex tunetanus.Flavonoids and tannins were the principal groups.Results suggest the potential of Rumex tunetanus as a source of bioactive ingredients.