Chemical and Biological Properties of Sodium Alginates Isolated from Tow Brown Algae Dictyopteris Membranaceae and Padina Pavonica

Polysaccharides are known to have interesting biological activities. To date polysaccharides extracted from Tunisian seaweed have not been fully studied. In this paper we tried to isolate sodium alginate from two brown algae and evaluate their biological activities. Two brown seaweeds Dictyopteris membranaceae and Padina pavonica were treated with selective solvents to extract sodium alginate. Analyses were performed to determine their IR spectra, uronic acid’s content and biological properties (antioxidant and gastroprotective activities). Results showed that sodium alginate extracted from D. membranaceae contained 65% of uronic acid while this extracted from P. pavonica contained only 9% of uronic acid. These polysaccharides showed also variation in the structure and the activities. Sodium alginate extracted from D. membranaceae had the highest antioxidant activity with ED50 of 20µg/ml in the DPPH test. Additionally, this polysaccharide had the most important gastroprotective activity with a percent of 97% at dose 50mg/kg. Our finding suggested that sodium alginates extracted from D. membranaceae and P. pavonica could be used as a natural source of antioxidant and gastroprotective agents. &nbsp

Anti-inflammatory and analgesic activities with gastroprotective effect of semi-purified fractions and isolation of pure compounds from Mediterranean gorgonian Eunicella singularis.

Abstract Objective To explore anti-inflammatory activities of organic extract and its semi-purified fractions (ethanol, acetone, methanol/dichloromethane) from the Mediterranean gorgonian Eunicella singularis. Methods The anti-inflammatory and analgesic activities were evaluated, using the carrageenan-induced rat paw edema model and the acetic acid writhing test in mice. The gastroprotective activity was determined using HCl/EtOH induced gastric ulcers in rats. The purification and structure elucidation of compound(s) from the more effective fraction were determined by chromatographic and spectroscopic methods and in comparison with data reported in the literature. Results The fraction F–EtOH showed an important anti-inflammatory activity associated with significant analgesic and gastroprotective properties. The purification and structure elucidation of compound(s) from this fraction lead to the identification of one diterpenoid and four sterols. Conclusions These results suggested that components from the active fraction can be used to treat various anti-inflammatory diseases

Anticonvulsant and analgesic activities of crude extract and its fractions of the defensive secretion from the Mediterranean sponge, Spongia officinalis.

International audienceABSTRACT: This study progresses in the direction of identifying component(s) from the Mediterranean sponge, Spongia officinalis with anticonvulsant and analgesic activities. We investigated the efficacy of crude extract and its semi-purified fractions (F1-F3) of the defensive secretion from Spongia officinalis for their in vivo anticonvulsant activity using the pentylenetetrazole (PTZ) seizure model and analgesic activity using the writhing test in mice. Among the series the crude extract exhibited interesting analgesic activity in a dose dependent manner. Similarly the fraction F2 showed a partial protection of mice from PTZ-induced seizure and interesting analgesic activity in a dose dependent manner. The purification and the determination of chemical structure(s) of compound(s) of this active fraction are under investigation

In vitro immunomodulatory activity and in vivo anti-inflammatory and analgesic potential with gastroprotective effect of the Mediterranean red alga Laurencia obtusa

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Anticancer activity of diterpenes and steroids from Eunicella singularis against two- and threedimensional breast cancer cell models

Objective: To investigate the anticancer activity of two diterpenes [palmonine F (C1) and palmonine D (C2)] and three steroids [cholesta-5,22-dien-3β-ol (C3), stigmasterol (C4) and 5α-cholest-5-en-3β-ol (C5)], isolated from the Mediterranean gorgonian Eunicella singularis, against MCF-7 breast cancer cell line. Methods: This study was performed on standard monolayer two-dimensional (2D) model to evaluate apoptosis by means of AnnexinV-FITC/PI flow cytometry and on three-dimensional (3D) spheroid model using Celigo imaging cytometer for spheroids size analysis. Results: Results indicated that both diterpenes and steroids exhibited an important apoptotic activity in a concentration-dependent manner with EC50 values of 13, 49, 30, 66 and 65 μg/ mL for C1, C2, C3, C4 and C5, respectively. Treatment of MCF-7 3D cell model with C1–C5 induced growth regression of spheroids in a concentration-dependent manner similar to the clinical anti-breast cancer drug Taxol; over ten days of incubation, growth rates were < 1.5 at Day 10 with all tested compounds at 200 μg/mL. Conclusions: The present study indicates that the two diterpenes C1 and C2 and the three steroids C3, C4 and C5, isolated from Eunicella singularis, might be used as anti-breast cancer candidate drugs for further development