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Background: Maclura pomifera a member of Moraceae family, is a tropical plant with ethnobotanical uses. Objectives: The present study aimed to evaluate bioactive compounds, antioxidants, and acetylcholinesterase (AChE) inhibitory activities of different extracts of Tunisia M. pomifera (Rafin.) Schneid fruit in vitro and in vivo. Methods: Organic extracts in different polarities (chloroform, ethyl acetate, and acetone) were extracted from different parts of the fruit of M. pomifera (exocarp, mesocarp, and pips). Phenolic content, antioxidant activity, and anti-AChE activity were determined. The anti-amnesic effects of ethyl acetate extract of the exocarp of M. pomifera were measured in galactose-induced memory deficit mice by the Y maze. The levels of biomarkers and AChE activity were determined in brain tissues. Results: The obtained results showed that the ethyl acetate extract of exocarp contains the highest content of flavonoids and polyphenols 22.3mg quercetin equivalents per g of dry weight and 718.6 mg gallic acid equivalents per g of dry weight. The evaluation of antioxidant activities highlighted that the ethyl acetate extract of exocarp was the most active element. The study of the AChE inhibitory power demonstrated that the ethyl acetate extract of the exocarp had the greatest inhibitory activity. The ethyl acetate extract from the exocarp ameliorated cognitive performance and reversed the oxidative damage as compared to galactose group. Conclusion: M. pomifera fruit is a good source of natural antioxidants, which might help prevent oxidative stress-related damage and memory impairment in such mental disorders as Alzheimer’s disease (AD).

The objective of the current study was to compare the mycochemical composition and biological activities of two extracts (aqueous extracts and ground materials prepared with the QUENCHER approach) of three wild Basidiomy-cetes, Agaricus vaporarius, Lactarius deliciosus, and Lycoperdon pyriforme, collected from a region located in the north of Tunisia. Mycochemical analysis in terms of total phenolic compounds, flavonoids, flavanols, proanthocyanidins, and tannin contents were determined. In addition, the antioxidant activities of the mushrooms were evaluated using three assays (2,2-di-phenyl-1-picrylhydrazyl free radical scavenging, ferric reducing antioxidant power assay, and metal chelating assay). Their antimicrobial activities were assessed against seven bacterial species. The obtained data revealed the presence of significant differences between secondary metabolites and the biological activities of the different tested extracts. Extracts of Basidiomy-cetes prepared with the QUENCHER approach had higher total phenolic content and antimicrobial activity against the evaluated strains. Antioxidant activity showed that the water extract had the greatest activity. The water extracts were analyzed with high-performance liquid chromatography, and the results showed that these three wild macromycetes contain a wide variety of antioxidant compounds in addition to many other bioactive compounds of nutritional and therapeutic interest.

The phenolic, flavonoid, tannin and proanthocyanidin content of the lichen Cladonia foliacea with and without its lichenicolous fungus Heterocephalacria (Syzygospora) bachmannii was investigated. The phenolic compounds were quantified in organic extracts using ultrasonic extraction (acetone and methanol) and in milled material (the ground material diluted with microcrystalline cellulose). The total phenolic content depended on the solvent polarity, the extraction technique and the species. The results demonstrated that the highest total phenolic content was recorded in untreated milled material (935.75 μg GAE/g DW) of H. bachmannii plus C. foliacea, followed by C. foliacea (668.29 μg GAE/g DW). The antioxidant activities were evaluated by the in vitro scavenging capacity, iron reducing power, and iron chelating power. The results showed that the highest scavenging capacity were obtained in methanol extracts of C. foliacea with IC50 = 0.015 mg/mL, followed by methanolic extract of H. bachmannii plus C. foliacea that had a scavenging capacity and iron reducing power of (IC50 = 0.030 mg/mL and IC50 = 0.054 mg/mL, respectively). The milled material showed the highest iron chelating power (IC50 = 0.279 mg/mL). We conclude that Cladonia foliacea when parasitized by H. bachmannii possesses a high antioxidant potential in the methanolic extract. Acetone and methanol extracts, showed that extracts from lichen plus lichenicolous fungus contained different and possibly more effective bioactive molecules than the lichen alone. These included phenolic acids, alkanes and aromatic compounds. This is the first study to investigate the phenolic content and antioxidant capacity of a lichenicolous fungus, albeit based on differences between the lichen with and without the mycoparasite H. bachmannii .

The composition and antioxidant activity of the essential oil of Carya illinoinensis were evaluated in this research. The yield of essential oils from three varieties was found to vary from...

International audience; This study aimed to investigate the effect of the maturation process of sweet marjoram (Origanum majorana L.) on essential oil composition, the phenolic profile of ethanolic extract and their antioxidant capacities. The essential oil composition was studied at three stages of maturity by GC–MS. Thirty compounds were detected representing 100% of the total essential oil. p-Menth-1-en-4-ol was the major compound (37.15–76.94%) followed by cyclohexanol-3,3,5 trimethyl (5.41–15.99%) and α-terpineol (0.94–11.34%). During the maturation process, an accumulation of oxygenated monoterpenes was observed. The phenolic composition was studied using matrix-assisted laser desorption/ionization time of flight. The analysis showed the presence of short flavonoid monomers at all stages of maturation. The antioxidant capacity of ethanolic extracts and essential oils was evaluated using the DPPH assay, iron chelating power and reducing power assay. The highest phenolic content and antioxidant capacity were found at flowering stage. These findings on essential oil composition, phenolic profile and antioxidant capacity of O. majorana at three different stages of development provide more information on how these secondary metabolites are accumulated.

Context: Ruta genus (Rutaceae) is abundantly used and described in the most ancient systematic records of medical practice of the Mediterranean world. In Tunisia, this genus is represented by two medicinal and aromatic shrubs: Ruta chalepensis L. and Ruta montana L. Objective: This study investigates the antioxidant and acetylcholinesterase inhibition (AChE) activities before and after in vitro gastrointestinal metabolism of leaf decoction of R. chalepensis and R. montana. Materials and methods: We study, in vitro, the effect of the gastrointestinal juices gastric (1.75 mL) or pancreatic (2.5 mL) juices, on the biological activity by the measurement of the antioxidant activity and AChE inhibition during 4 h of decoction extract obtained from the leaves of the two species of Ruta. Results: The results showed that the ability to inhibit the AChE enzyme was similar; being the greatest inhibitory activity exhibited by the ethanol extract (IC50 = 12 ± 1.1 μg/mL) obtained from leaves of R. chalepensis. Conclusion: In conclusion, we showed that there was no appreciable degradation and that the activity was kept constant after gastric and pancreatic juice digestion.

The comprehensive phenolic fingerprint of Calligonum azel Maire plant fractions, collected from the Tunisian Desert, have been assessed for the first time as a source of natural antioxidants. Total phenolic content (TPC), Trolox Equivalent Antioxidant Capacity (TEAC) in scavenging DPPH, ABTS+ and Ferric Reducing Antioxidant Power (FRAP) were determined. C. azel Maire showed a relevant content in phenolic compounds, which are related to the antioxidant activity. The flowers presented the highest antioxidant capacity against DPPH free radicals, while the leaves showed the highest scavenging capacity against ABTS. As for the FRAP assay, results showed that the roots had the highest ferric reducing antioxidant power. Methanol extracts of the four organs were screened by ultra high performance liquid chromatography coupled to quadruple time of flight mass spectrometry and the identified phenolics were further quantified. Flavones and flavanols were the most abundant phenolic compounds identified, and were quantitatively measured as luteolin and catechin equivalents. Although the phenolic profile was diverse between the four organs, the obtained results showed that Calligonum azel Maire is an excellent source of various natural antioxidants with high radical scavenging capacities, which could be used in food preservation. Further studies on the isolation of such compounds appear to be of high interest.

Thapsia garganica phytotoxicity was studied on Lactuca sativa L. and associated weeds, by pulverization of its aqueous extracts (at 10, 20, and 30 %), in pot experiments. To comprehend its mode of action on lettuce, seedlings were grown hydroponically in Hoagland nutrient solution for two months, then the T. garganica leaves aqueous extract was added to the medium for three days. After the harvest, a number of physiological and biochemical parameters had been determined. The antioxidant activity for DPPH (2,2-diphenyl-1-picrylhydrazyl radical) and FRAP (Ferric reducing antioxidant power), and secondary metabolite production were assessed by employing QUENCHER approach. The pulverization treatment was beneficial for lettuce growth, whose length of different organs has been improved at all concentrations. However, it has been very harmful to weeds and in a more important way to monocotyledons, which were totally burned at 30 %, compared to dicotyledons weeds. To allelopathic stress, lettuce developed a defense strategy manifested by a decrease of electrolyte leakage and malondialdehyde content (MDA), an increase in proline content and in polyphenols, flavonoids, flavanols, proanthocyanidins, condensed tannins and carotenoids production. Similarly, a stimulation of the antioxidant activity was recorded, by increasing DPPH free radical-scavenging activity and ferric reducing antioxidant power. For lyase type enzymes (the phenylalanine ammonia-lyase (PAL) and the tyrosine ammonia-lyase (TAL)) activities, an improvement of 25.00 % for the PAL and 38.00 % for the TAL were registered in roots and leaves, respectively. Chlorophyll contents were similarly affected, however the respiration decreased. T. garganica is a species rich in allelochemicals compounds, according to its allelopathic potential. The possibility of using its aqueous extract by spraying shows that it could be an ecofriendly approach to exploit its valuable allelochemicals.

International audience; This study is the first to investigate the chemical composition of barks essential oil (EO), secondary metabolites and biological activities of the MeOH and infusions extracts of seeds, leaves, barks and roots of Calligonum azel Maire (Polygonaceae) harvested from Tunisian desert. The gas chromatography/mass spectrometry (GC/MS) results showed the presence of fifty-four compounds in barks EO. The major components were: viridiflorol (14.6%), α-eudesmol (8.65%), trans-caryophyllene (6.72%), elemol (6.63%), β-eudesmol (6.21%). The obtained results showed that C. azel is a very rich plant in secondary metabolites. High contents in polyphenols, flavonoids and tannins were observed in both extracts of all studied organs. Significant differences were found between both extracts of the four organs. Thus, polyphenols and tannins were more abundant in leaves infusion extract, while, flavonoids showed a high level in barks extract. The antioxidant activity data demonstrated that all extracts showed strong antioxidant and radical scavenging activities. The MeOH extracts presented potential for antibacterial and antifungal activities against all tested microorganisms. The inhibition zones diameters and minimal inhibitrice concentration values were in the range of 9 - 15 mm and 2.5 - 20 μg/ml, respectively. This study demonstrated that C. azel can be regarded as an excellent plant source for natural antimicrobial agents.