Neorogioltriol: A brominated diterpene with analgesic activity from Laurencia glandulifera

International audienceThe new tricyclic brominated diterpenoid, neorogioltriol (1), was isolated from the organic extract of the red alga Laurencia glandulifera, collected at Kefalonia Island in Western Greece. Assignment of the (1)H and (13)C NMR resonances were carried out by extensive analysis of its NMR spectra. The new metabolite was evaluated for its analgesic activity using the writhing test in mice and the formalin test in rats. A dose-dependant antiinociceptive response was observed in the writhing test at 0.5 and 1 mg/kg with an IC(50) of 12.5 mu g/kg. Compound 1 also inhibited the second phase of the formalin test. (c) 2008 Phytochemical Society of Europe Published by Elsevier B.V. All rights reserved

In Vivo and in Vitro Anti-Inflammatory Activity of Neorogioltriol, a New Diterpene Extracted from the Red Algae Laurencia glandulifera

Neorogioltriol is a tricyclic brominated diterpenoid isolated from the organic extract of the red algae Laurencia glandulifera. In the present study, the anti-inflammatory effects of neorogioltriol were evaluated both in vivo using carrageenan-induced paw edema and in vitro on lipopolysaccharide (LPS)-treated Raw264.7 macrophages. The in vivo study demonstrated that the administration of 1 mg/kg of neorogioltriol resulted in the significant reduction of carregeenan-induced rat edema. In vitro, our results show that neorogioltriol treatment decreased the luciferase activity in LPS-stimulated Raw264.7 cells, stably transfected with the NF-κB-dependent luciferase reporter. This effect on NF-κB activation is not mediated through MAPK pathways. The inhibition of NF-κB activity correlates with decreased levels of LPS-induced tumor necrosis factor-alpha (TNFα) present in neorogioltriol treated supernatant cell culture. Further analyses indicated that this product also significantly inhibited the release of nitric oxide and the expression of cyclooxygenase-2 (COX-2) in LPS-stimulated Raw264.7 cells. These latter effects could only be observed for neorogioltriol concentrations below 62.5 μM. To our knowledge, this is the first report describing a molecule derived from Laurencia glandulifera with anti-inflammatory activity both in vivo and in vitro. The effect demonstrated in vitro may be explained by the inhibition of the LPS-induced NF-κB activation and TNFα production. NO release and COX-2 expression may reinforce this effect

Analgesic and Antioxidant Activities of Algerian Retama raetam (Forssk.) Webb & Berthel Extracts

Part of this work deals with t he isolation and structure elucidation of the main polar secondary metabolites of the aerial parts of Retama raetam (Forssk.) Webb & Berthel, as well as the evaluation of their potential analgesic properties , while the rest deals with the antioxidant activities of the aqueous extracts of roots, stem, fruits and flowers of the plant . It was found that the isoflavones g enistein 1, 6-hydroxygenistein 2, 3'-O-methylorobol 3, pratensein 4, biochanin A 8, the flavones 6-hydroxyapigenin 7 and luteolin 5, the flavonol kaempferol 6,as well as the phenolic compound p-coumaric acid 9 reduce significantly the pain at a concentration dose of 1 mg/kg. The most active compounds were 3 and 8 (86.19% and 75.23%, respectively). The obtained aqueous extracts of R. raetam were also evaluated for their antioxidant activities using two different photometric methods; the results revealed that all extracts exerted very low free radical scavenging activity compared to the well-known butylated hydroxytoluene (BHT) and lower hydrogen peroxide blocking activity than positive control gallic acid

Optimization of enzymatic saccharification of Chaetomorpha linum biomass for the production of macroalgae-based third generation bioethanol

To evaluate the efficacy of marine macro-algae Chaetomorpha linum as a potential biofuel resource, the effects of the enzymatic treatment conditions on sugar yield were evaluated using a three factor three level Box-Behnken design. The hydrothermally pretreated C. linum biomass was treated with Aspergillus niger cellulase at various liquid to solid ratios (50–100 mL/g), enzyme concentrations (10–60 U/g) and incubations times (4–44 h). Data obtained from the response surface methodology were subjected to the analysis of variance and analyzed using a second order polynomial equation. The fitted model was found to be robust and was used to optimize the sugar yield (%) during enzymatic hydrolysis. The optimum saccharification conditions were: L/S ratio 100 mL/g; enzyme concentration 52 U/g; and time 44 h. Their application led to a maximum sugar yield of 30.2 g/100g dry matter. Saccharomyces cerevisiae fermentation of the algal hydrolysate provided 8.6 g ethanol/100g dry matter. These results showed a promising future of applying C. linum biomass as potential feedstock for third generation bioethanol production