New Synthesized Derivatives from N-Substituted-4-Oxo-[1] Benzopyrano [4,3-c] Pyrazole Influenced Proliferation, Viability, Spreading and Invasion of Human Liver Tumor Cells

Background/Aim: There is an unsatisfied clinical demand to develop new anticancer agents. The aim of the current study was to synthesize new coumarin derivatives using two different synthetic methodologies and to evaluate their anticancer activity. Materials and methods: Four coumarin derivatives were synthesized and evaluated for their anticancer activities. The structures of all compounds were confirmed by infrared (IR), UV-vis, Nuclear magnetic resonance (NMR) 13C NMR, 1H NMR, and high-resolution mass spectrometry (HRMS) analysis. All the synthesized compounds (4, 5, 8 and 9) were analyzed for their anti-proliferative (MTT and LDH assays and cell cycle studied with flow cytometry) and anti-invasive activity (spreading and invasion tests) on human hepatoma cell lines Huh-7 in vitro. Doxorubicin was used as control in order to compare their anti-tumoral effects. Results. All the synthesized compounds are potential inhibitors of proliferation, viability, spreading and invasion of human liver tumor cells with a 50% inhibitory Concentration range,  IC50=10.37 μM to 12.94 μM. Conclusion. This study could lead to the identification of a new target therapy for human Hepatocellular carcinoma (HCC) or other cancers

Mecanisme de la catalyse par l'heparine, le dermatane sulfate et d'autres polysaccharides de la reaction d'inhibition de la thrombine par l'antithrombine III ou par le deuxieme cofacteur de l'heparine

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : T 83149 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Access to new anticoagulant by sulfation of pectin-like polysaccharides isolated from Opuntia ficus indica cladodes

International audienceIn order to develop new and low cost anticoagulants as potential heparin alternatives, sulfation of a pectin-like polysaccharide from Opuntia ficus indica cladodes using SO3-DMF complex was performed with a significant sulfate content (7%). FTIR and NMR assays indicated that the sulfation reaction had occurred. In addition, GC–MS analyses demonstrated that sulfation was carried out on the arabinose units of native polysaccharide. Moreover, Physico-chemical characterization indicated an evident decrease of the average molecular weight (Mw) and sugar rates after sulfation. Finally, anticoagulant assays demonstrated that the anticoagulant activity was significantly enhanced by the addition of sulfate groups. Thus, sulfated polysaccharides exhibited the most potent anticoagulant activity by prolonging activated partial thromboplastin time (APTT) and thrombin time (TT)

Characterization of Probiotic Properties of <i>Lacticaseibacillus paracasei</i> L2 Isolated from a Traditional Fermented Food “Lben”

Lben is a dairy fermented food that is largely consumed in Tunisia for its numerous health benefits that are related to the existence of probiotics. Lactic Acid Bacteria (LAB) are well known for their beneficial probiotic properties for humans, especially when administered in adequate amounts. The aim of this study was to isolate and investigate the probiotics properties of Lacticaseibacillus paracasei L2 from Lben. The isolated strain was identified by 16S r-RNA gene sequences and MALDI- TOF MS. To evaluate the probiotic potential of the isolated bacterium, in vitro tests were performed, including adhesion ability to HCT-116 cells, survival in acid and bile salt conditions, lysozyme resistance, biofilm formation, hemolytic activity, antioxidant activity, and antimicrobial activity. Our results revealed that the selected Lacticaseibacillus paracasei L2 strain expressed a high adherence to HCT-116 cells (45.03%), survived under acidic conditions (pH3), and showed a resistance to bile salts. The strain was considered as safe (α-hemolysis). L. paracasei L2 showed a high biofilm-formation ability (OD 570 > 1.7) after 24 h of incubation. It also demonstrated an important antioxidant activity in the range of 85.31% for the intact cells. However, an antimicrobial activity against pathogens, namely Staphylococcus aureus, was detected with an IZ that was above 19 mm. In conjunction with the results obtained and the technological properties of Lacticaseibacillus paracasei L2 (proteolytic property, autolytic activity, acidifying activity, and EPS production), this strain may be used as a probiotic for manufacturing fermented foods

Exploring the Exopolysaccharide Production Potential of Bacterial Strains Isolated from Tunisian Blue Crab <i>Portunus segnis</i> Microbiota

The blue crab (BC) Portunus segnis is considered an invasive species colonizing Tunisian coasts since 2014. This work aims to explore its associated bacteria potential to produce anionic exopolysaccharides (EPSs) in order to open up new ways of valorization. In this study, different BC samples were collected from the coastal area of Sfax, Tunisia. First, bacterial DNA was extracted from seven different fractions (flesh, gills, viscera, carapace scraping water, and three wastewaters from the production plant) and then sequenced using the metabarcoding approach targeting the V3-V4 region of the 16S rDNA to describe their microbiota composition. Metabarcoding data showed that the dominant bacterial genera were mainly Psychrobacter, Vagococcus, and Vibrio. In parallel, plate counting assays were performed on different culture media, and about 250 bacterial strains were isolated and identified by sequencing the 16S rDNA. EPS production by this new bacterial diversity was assessed to identify new compounds of biotechnological interest. The identification of the bacterial strains in the collection confirmed the dominance of Psychrobacter spp. strains. Among them, 43 were identified as EPS producers, as revealed by Stains-all dye in agarose gel electrophoresis. A Buttiauxella strain produced an EPS rich in both neutral sugars including rare sugars such as rhamnose and fucose and uronic acids. This original composition allows us to assume its potential for biotechnological applications and, more particularly, for developing innovative therapeutics. This study highlights bacterial strains associated with BC; they are a new untapped source for discovering innovative bioactive compounds for health and cosmetic applications, such as anionic EPS

Optimization of polysaccharides extraction from quince peels: partial characterization, antioxidant and antiproliferative properties

International audienc