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DAS‐ELISA was used to study the presence of viruses in four aphid species (Aphis gossypii, Aphis craccivora, Myzus persicae and Macrosiphum euphorbiae) and in their host plants potato, capsicum and tomato. Samples were collected in different regions in Tunisia: north, Cap Bon, Sahel, centre and south. A. gossypii and M. persicae carried all the viruses detected: Cucumber mosaic cucumovirus, Tomato aspermy cucumovirus, Tobacco etch potyvirus, Potato Y potyvirus, Alfalfa mosaic alfamovirus and Potato leafroll polerovirus. These two aphids were also those that occurred most frequently on the crops concerned.

The aqueous-acetone polyphenolic extract of the traditionally derived date syrup, known as "Rub El Tamer", was analyzed using RP-HPLC-DAD and ESI-MS. The phenolic content of the extract was 394.53 ± 1.13 mg per 100 g of syrup with caffeoylsinapylquinic acid as the most abundant compound (72.23%). The extract exhibited strong antioxidant activities as evaluated using the ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)), DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) methods. The extract antimicrobial potential against a range of microorganism strains showed that Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus cereus were the most sensitive bacteria with MBC in the range of 0.5-0.05 mg/mL. Furthermore, in the presence of the syrup extract (8.18-131 μg/mL), the Human SH-SY5Y neuroblastoma and the 3T3 fibroblast cell lines showed dissimilar reduction of viability suggesting a higher cytotoxic effect against tumorigenic cells. Our results provide new insights into date syrup characterization which should stimulate further studies of this hot desert resource.

The traditional medicinal properties of Carpobrotus edulis are well recognized, particularly in Tunisia where it is used for wound healing. Thus, in this study, biochemical and molecular properties of its leaves' bioactive aqueous-acetone extract were investigated. The total phenolic content (TPC) of the extract was estimated to be 184 ± 5 mg/100 g of fresh matter (FM). The qualitative and quantitative polyphenolic profile was determined by ultra performance liquid chromatography with diode array detection (UPLC-DAD) and showed that chlorogenic acid was the major compound (43.7%). The extract exhibits potent antioxidant capacities with IC50 = 56.19 and 58.91 μg/ml, as accessed via the anionic DPPH and cationic ABTS radical scavenging assays, respectively. The extract has high antibacterial properties, especially against the Gram+ Staphylococcus aureus and Bacillus cereus strains. To investigate the extract effect on regeneration, the flatworm Dugesia sicula Lepori, 1948, was used as a model. The macroscopic analysis of planarian cultures in ordinary medium containing phenolic extract at non-toxic concentrations illustrated that the extract caused morphological changes. Additionally, the molecular study through the fluorescence-activated cell sorting (FACS) technique showed that C. edulis polyphenols can harm the stem cells' development. These results emphasize the ecotoxicological impact of phenolic rejections in the environment on flatworms' physiology.

slight increase of the extractable polyphenolics in PS and MS during the storage might explain in part the relatively limited decrease of GTPS and GTMS total phenolic content. However, chromatographic examination proved that some tea compounds, particularly caffeine, were preserved following PS and MS supplementation. Likewise, syrups'addition to GT significantly (P<0.5) limited the reduction of its antioxidant capacity as revealed by the DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azino-bis-(3-ethylbenzthialzoline-6-sulfonic acid)) assays. As expected, the antimicrobial trials showed that Gram (+) Staphylococcus aureus and Staphylococcus epidermidis were the most sensitive strains to tea polyphenols. The syrups supplementation noticeably preserved the tea bacteriostatic and bactericide activities during storage. The obtained analytical results demonstrate that MS or PS addition to green tea beverage stabilized its polyphenolic content and biofunctional properties during refrigerated storage, thus, scientifically supporting this popular practice in the Mediterranean countries.

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Fourteen microsatellite loci were isolated and characterized in the potato aphid, Macrosiphum euphorbiae Thomas, by screening a genomic library with the oligonucleotide probes (GA)10 (GT)10 and (GATA)4. Allelic diversity was estimated in samples collected from potato fields in Tunisia. Ten loci displayed polymorphism that ranged from two to four alleles per locus and the observed heterozygosity ranged from zero to one. These markers could be used to study the population genetic structure of this polyphagous aphid species.