Seeds from five varieties of Tunisian Citrus fruits, namely blood orange ( Citrus sinensis ), sweet orange ( Citrus sinensis ), lemon ( Citrus limon L.), bergamot ( Citrus bergamia ) and bitter orange ( Citrus aurantium ), were examined for their composition of lipid classes and fatty acids. In addition, the oil yield, total fatty acids, palmitic, oleic and linoleic acids were determined. Petroleum ether-extracted oils of these Citrus seeds amounted to more than 78% in the case of lemon seeds. The Citrus seed oils had three lipid classes as determined by thin-layer chromatography. Triacylglycerols were the major oil class in all varieties. Gas chromatographic analyses revealed that the main fatty acids were palmitic, oleic and linoleic acids.

This research evaluated the effect of saline conditions on fruit yield, fatty acids, and essential oils compositions and phenolics content of black cumin (Nigella sativa). This plant is one of the most commonly found aromatics in the Mediterranean kitchen. Increasing NaCl levels to 60 mM decreased significantly the fruits yield by 58% and the total fatty acids amount by 35%. Fatty acids composition analysis indicated that linoleic acid was the major fatty acid (58.09%) followed by oleic (19.21%) and palmitic (14.77%) acids. Salinity enhanced the linoleic acid percentage but did not affect the unsaturation degree of the fatty acids pool and thus the oil quality. The essential oil yield was 0.39% based on the dry weight and increased to 0.53, 0.56, and 0.72% at 20, 40, and 60 mM NaCl. Salinity results on the modification of the essential oil chemotype from p-cymene in controls to γ-terpinene/p-cymene in salt-stressed plants. The amounts of total phenolics were lower in the treated plants. Salinity decreased mainly the amount of the major class, benzoics acids, by 24, 29, and 44% at 20, 40, and 60 mM NaCl. The results suggest that salt treatment may regulate bioactive compounds production in black cumin fruits, influencing their nutritional and industrial values.

Four samples of Tunisian virgin olive oils of Chetoui, Chemlali, Chemchali and Oueslati varieties were analyzed for their chemical and fatty acid, total chlorophyll, total polyphenol and total aroma contents. The results showed that Chetoui was the most pigmented oil (4.45 ppm) and Oueslati oil contained the smallest amount of total chlorophylls (1.29 ppm). The Chetoui oil had the highest amount (94.37 ppm) of total polyphenols, while the Oueslati had the lowest amount (65.5 ppm). Furthermore, the Chemchali oil contained the highest level of total aroma (55.49 µg/mL of oil), followed by the Chemlali, Chetoui and Oueslati oils. The Chetoui oil was characterized by the highest level of oleic acid (70.9%) in contrast to the Chemlali, which had the lowest level of this fatty acid (58.6%). In addition, the highest level of palmitic acid characterizes the oil Chemlali (19.7%), whereas the Chetoui had the lowest (9.1%).

Plant biodiversity is endowed with a huge composition and variability of active molecules known for their therapeutic effects against several diseases. In this current work, several phenolic compounds are subject of in silico evaluation of their interactions with six severe acute respiratory syndrome coronavirus (SARS-CoV) enzymes to evaluate the binding mode and mechanism of phenolic compounds interactions with SARS-CoV-2 enzymes. Results of molecular docking and data analysis revealed that the importance of interactions was dependent to the phenolic class of tested ligand; tannin, biflavone and flavonoid glycoside were the most interactive classes. Among the top three ranked molecules recording lower binding energy against each virus protein target, In conclusion, it was found that Amentoflavone, Dieckol, Bilobetin, Punicalagin, Tellimagrandin-I, Tannic acid, Sciadopitysin, Ginkgetin and Chebulagic acid could be a promising antiviral drug since they present more important binding energy than conventional ones. Their interactions were justified by the Wenn diagram and Ramachandran plot. However, these phenolic compounds recorded an important bioavailability score and found fulfilling most of the drug-likeness criteria such as Lipinski's rule. Clearly, all observations point to further required works aiming to examine more deeply the possibility of using these molecules that could be probably a subject of pre-clinical studies.

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