Contribution to the phytochemical study and evaluation of the biological potential of Salsola tetragona Delile

This study was conducted on the plant Salsola tetragona Delile, which is a medicinal desert plant belonging to the Amaranthaceae family, spreading in the saline areas located in the northeast of the Oued Souf region. The aim was to determine its nutritional value and assess the secondary metabolite products, as well as understand the chemical composition of this plant and try to determine the extent of biological effectiveness that characterizes it. This is in order to verify what has been mentioned regarding its use in traditional medicine, as well as an attempt to exploit it in the pharmaceutical field.
Chemical analyses of the nutritional value showed that the biomass of the aerial part of S.tetragona plant is characterized by a considerable mineral content, distinguished by the abundance of most elements, as it contains an important moisture content indicating its ability to withstand harsh desert growing conditions. It also contains average rates of carbohydrates, lipids and proteins. The qualitative phytochemical examination of the crude extract of the aerial part of the S. tetragona plant, showed that it contains most secondary metabolites including alkaloids, coumarins, mucilages, phenols, saponins, sterols and terpenes. Quantitatively, the quantitative estimation of the crude extract and the five fractions derived from it, which are the n-hexane, dichloromethane, ethyl acetate, n-butanol and the remaining aqueous fractions, showed the presence of considerable amounts of phenols, flavonoids, tannins and terpenes which were relatively close in all fractions. Meanwhile, LC-HR/MS analysis of the crude hydromethanolic extract of S. tetragona plant revealed the presence of 16 phenolic compounds, 11 of which appear for the first time in the Salsola genus, including salicylic acid, ascorbic acid and naringenin as the most abundant elements. While GC/MS analysis of the n-hexane fraction revealed the presence of 7 compounds, 5 of which appear for the first time in this genus, 3 compounds were distinguished by the highest abundance which are hexadecanoic acid methyl ester (23.48%), bis-(2-ethylhexyl) phthalate (21.98%), 8,11-octadecadienoic acid methyl ester (18.49%).
The antioxidant capacity was evaluated using DPPHo, FRAP, ABTSo+, CUPRAC, anti-hemolysis and metal chelating assays. The dichloromethane fraction showed superiority in the DPPHo and ABTSo+ assays, while the ethyl acetate fraction was superior in the CUPRAC assay. The hexane fraction had the greatest ability to chelate Fe2+ ions in the metal chelating assay, and also had the highest ability to protect red blood cells from hemolysis in the anti-hemolysis assay. In the anti-inflammatory assay, the ethyl acetate fraction showed strong inhibitory activity against inflammatory protein denaturation, with an IC50 value of 13 ł5 ?g/mL, superior to that of the standard Aspirinʼ. Regarding the fractions' activity in inhibiting bacterial growth, all fractions showed moderate antibacterial activity against both Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae strains.
For antidiabetic activity, the ethyl acetate and n-butanol fractions showed strong inhibition of ?-amylase and ?-glucosidase enzymes, with an IC50 of 70 ?g/ml for both, indicating good potential for developing this plant for treating type 2 diabetes. For acetylcholinesterase enzyme inhibition related to Alzheimer's disease, the n-butanol fraction showed the highest inhibitory activity with an IC50 of 30 ł 0.30 ?g/ml, suggesting its potential for alleviating symptoms of this disease. Regarding cytotoxicity testing against MCF7 breast cancer cells, the dichloromethane fraction showed high efficacy, outperforming the other fractions with the highest inhibition value of IC50 = 98 ?g/mL. It and the ethyl acetate fraction also showed significant activity in the anti-SARS-CoV2 assay.