Exploitation of somaclonal variability for the search of saline-tolerant potato (Solanum Tuberosum L.)

The present investigation was conducted with an aim to study the effect of salt stress (NaCl) on in vitro potato callus growth and the potential for exploiting this technique in improving salinity tolerance in potato. The results in the four varieties in the culture medium showed a decrease in all studied parameters like callus growth, relative average growth, water content and salinity sensitivity coefficient upon increasing the salinity of the medium in calluses. It has also been observed that the type of callus has a large effect on the above-mentioned parameters in which better callus growth adapted to 150 mmol NaCl is obtained than unsuitable calli in the same culture medium

Analyse Moléculaire De La Diversité Génétique Des Protéines De Réserves Chez Quatre Variétés De Blé Dur (Triticum turgidum L.var durum)

The molecular polymorphism of the stock proteins, namely, glutenin and gliadin has been studied in order to perform a comparison of the genes coding for these factors in the quality of bread as much as they are major contributors to the elasticity and formation of wheat dough. DNA markers for quality traits are currently being used by wheat breeders to directly measure traits and performing biochemical tests. The aim of this study was to use DNA markers to search for varieties with glutenin genes (HMW and LMW) and gliadin genes also. 4 durum wheat varieties (alexandrium, murcenese, italicum and valencia) were used for these genes using PCR/RFLP markers via (F-56) and (R-56) primers. Results obtained show that polymorphism rate of this two primer is 54.54%. These two primers produce the same number of amplifiers whose size is 536bp. A total of eleven fragments are obtained for each primer. Five are relatively polymorphic, which concerns the genotype: 4, 20, 76, 91 and 92 through the pairing of an expression density materialized by low intensity bands. The study also revealed that there was no product at 527bp, the size of (HMW) glutenin gene; this indicates that the 100 genotypes do not contain this gene. Thus indicating its poverty in this element; compared to the (LMW) subunit of this gene which accounts for about 60% of glutenin proteins. While there is 770bp product for the gliadin gene, which indicates also that the 100 genotypes contain this gene. Thus indicating its good quality for bread making

Theoretical investigation on two different mechanisms of fulleropyrrolidine formation

International audienceFulleropyrrolidine synthesis by photo-addition of glycine methyl ester (GME) to [60] fullerene has been recently realized and experimentally studied. Two possible hypotheses were suggested for its formation pathway, but there was no consensus about the most favorable one. Thus, in order to find the most probable mechanism, we performed a detailed theoretical investigation of the reaction between GME and [60] fullerene studying both mechanisms suggested experimentally. The first hypothesis involves two additions of two GME radicals in two steps to C-60 followed by a NH3 departure, whereas the second one involves azomethine ylide formation in a first step and followed by a cycloaddition to [60] fullerene. All the transition states and the intermediates in the reaction steps for both mechanisms were determined. The energetic profiles of both mechanisms were drawn and compared. Several levels of theory were used for the purpose, with the aim to investigate which low-cost level is sufficient to settle and which mechanism is probably involved. For the purpose, semiempirical (AM1), DFT on geometries optimized at AM1 level, and finally DFT on geometries optimized at DFT level were considered. At DFT level, GGA (PBE), hybrid (PBE0) and meta-GGA (M06-2X) were used, with a 6-31+ G(d) basis set. We proved that the release of NH3 and the ring formation step in the first mechanism require a higher energy barrier compared to the second mechanism reaction steps like tautomerization and H2O departure. Thus, we can conclude that the second mechanism involving in a first step the azomethine ylide formation is more favorable than the first mechanism. The interest in using in a first step a semiempirical determination of reaction paths is highlighted, and the choice of the exchange-correlation functional is discussed

Photoionization of Benzophenone in the Gas Phase: Theory and Experiment

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Antioxidant potentials and inhibitory activities of α-amylase, α-glucosidase, and acetylcholinesterase of different fractions from Salsola tetragona Delile

ABSTRACTThe medicinal use of Salsola tetragona Delile (Amaranthaceae) aerial parts is a longstanding tradition. This study delved into the plant’s potential as an antioxidant, anti-diabetic, and anti-Alzheimer agent. The aerial portion extracted and evaluated four fractions (n-hexane, dichloromethane, ethyl acetate, n-butanol) for their antioxidant activity using DPPH, FRAP, and anti-hemolysis tests, as well as the inhibitory activity of cholinesterase and carbohydrate digesting enzymes. The results showed that the dichloromethane fraction (St.DCM) of S. tetragona had a significant ability to scavenge DPPH• radicals. The ethyl acetate fraction (St.EtOAc) had the best reduction power test activity compared to other solvent fractions. The n-hexane fraction (St.Hex) was most effective in the anti-hemolysis test. The ethyl acetate fraction also had inhibitory activities (p < .05) with IC50 values of 70 ± 1.80 µg/ml for α-glycosidase, equivalent to the n-butanol fraction (St.n-BuOH), which had very significant activity (p < .05) in the α-amylase inhibition test with an IC50 of 64 ± 1.80 µg/ml. The ethyl acetate fraction also had a considerable concentration of total phenolic compounds and flavonoids and exhibited significant (p < .05) inhibitory effects on acetylcholinesterase with an IC50 of 30 ± 0.30 µg/ml. Therefore, the aerial parts of S. tetragona contained high levels of biologically active compounds, making it a potential source for developing new plant-based pharmaceuticals and nutraceuticals to enhance human health

Phytochemical profiling of Salsola tetragona Delile by LC-HR/MS and investigation of the antioxidant, anti-inflammatory, cytotoxic, antibacterial and anti-SARS-CoV-2 activities

This study aimed to investigate the phytochemical composition and biological activity of Salsola tetragona Delile. (Amaranthaceae), a medicinal plant. The study evaluated the antioxidant potential of the crude extract and five fractions of S. tetragona using DPPH•, ABTS•+, CUPRAC, and metal chelating assays. The anti-inflammatory activity was determined using a protein denaturation assay, and the antibacterial activity was determined by the Minimum inhibitory concentrations (MICs) for the growth of Escherichia coli and Staphylococcus aureus strains. The MTT test and an in vitro scratch assay evaluated the effects on cell viability and cell migration. The potential anti-SARS-CoV-2 activity was assessed by analyzing the effects on the interaction between ACE2 and Spike protein. The bioactive compounds present in the plant were identified using LC-HR/MS analysis. The crude hydromethanolic extract (STM) and five fractions of S. tetragona, n-hexane (STH), dichloromethane (STD), ethyl acetate (STE), n-butanol (STB), and aqueous (STW) showed significant antioxidant activity in four different tests. In the anti-inflammatory assay, the ethyl acetate fraction exhibited significantly higher activity than Aspirin® (IC50 = 13 ± 5 µg/mL). The crude extract and its fractions showed positive antibacterial activity with similar MICs. In the cytotoxicity assay against the breast cancer cell line MCF7, the dichloromethane fractions (STD) were very effective and demonstrated superiority over the other fractions (IC50 = 98 µg/mL). Moreover, the potential of the extract and fractions as anti-SARS-CoV-2, the ethyl acetate, and dichloromethane fractions demonstrated important activity in this test. LC-HR/MS analysis identified 16 different phenolic compounds, Eleven of which had not been previously reported in the genus Salsola. The results suggest that the extracts of S. tetragona have the potential to become new sources for developing plant-based therapies for managing a range of diseases

Biochemical Profile and In Vitro Therapeutic Properties of Two Euhalophytes, <i>Halocnemum strobilaceum</i> Pall. and <i>Suaeda fruticosa</i> (L.) Forske., Grown in the Sabkha Ecosystem in the Algerian Sahara

This study reports the biochemical profile and in vitro biological activities of the aerial part of two shrubs: Halocnemum strobilaceum and Suaeda fruticosa, a halophytes species native to saline habitats. The biomass was evaluated by determining its physiological properties and approximate composition. Hydro-methanolic extracts from Halocnemum strobilaceum and Suaeda fruticosa have been investigated for the inhibition of bacterial growth, the protection of proteins (albumin) from denaturation, and cytotoxicity to hepatocellular carcinomas (Huh-7 and HepG2). Their antioxidant activity was evaluated by five tests, including one that examined their ability to inhibit hydrogen peroxide (H2O2)-induced hemolysis. The profile of their phenolic compounds was also determined. These two euhalophytes had a high moisture content, high levels of photosynthetic pigments, elevated levels of ash and protein, low oxidative damage indices, MDA (Malondialdehyde) and proline, and low lipids levels. Their content was also characterized by a moderate acidity with good electrical conductivity. They contained abundant levels of phytochemicals and varied phenolic contents. Reverse phase high performance liquid chromatography (RP-HPLC) analysis revealed the presence of caffeic acid, p-coumaric acid, rutin, and quercetin in both plant extracts. On the pharmaceutical level, the two euhalophytes had anti-inflammatory, antibacterial, antioxidant, and cytotoxic properties, and therefore it was recommended to isolate and identify biologically active compounds from these plants and evaluate them in vivo

Large-scale participation in policy design: citizen proposals for rural development in Tunisia

International audienceMore and more literature and practice recommend involving the public at the early stages of the policy cycle, i.e. issue identification, definition of the policy objectives and policy design. Policy design involves, among others, identifying solutions, ideas or alternatives which may address the policy objectives. Three main arguments are often put forward to advocate for the involvement of stakeholders, or the public, in policy design: a "user-centered " argument (i.e. for the policy to better meet people's priorities), an innovation argument (i.e. to conceive new solutions) and a collective argument (i.e. to identify collective actions and better tackle environmental problems). However, in both research and practice these arguments have been challenged. Research has insufficiently generated evidence of the influence of large-scale participation in policy design on resulting proposed actions. The objective of this paper is to analyze whether a large-scale participatory process leads to action proposals that fit people's priorities and that are innovative and collective. It draws from a land management and rural development policy design experiment conducted in six vulnerable areas of Tunisia. 4,300 direct participants were involved and 11,583 action proposals were collected. Our results highlight the influence of the local circumstances on innovation and the interest towards collective actions. Our results also show that whether policy design is made individually or in group influences the outcomes. The results also suggest that appropriate facilitation can help fostering more collective and innovative actions. We conclude the paper by opening up the idea of hybridizing policy design methods with methods from political and agricultural sciences in order to better understand the drivers and rationalities behind participants' action proposals