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The beneficial effects of biochar, obtained from the carbonization of orchard pruning residues were analyzed on lettuce (Lactuca sativa L.) and tomato (Solanum lycopersicum Mil.) in a pot experiment with four substrates. Lettuce plants were grown in poor soil (PS), poor soil plus biochar (PSB), poor soil plus compost (PSC) and poor soil ((in term of carbon content and nitrogen content) plus compost and biochar (PSCB). Tomato plants were grown in poor soil (PS), poor soil plus biochar (PSB), rich soil (in term of carbon content and nitrogen content) (RS) and rich soil plus biochar (RSB). The effects of different substrates were assessed by chemical, physical and microbiological analysis of soil. Additionally, a first screening was done on the potential toxicity of biochar on plant seeds, using Lepidium sativum as model species, and earthworm (Lombricus terrestris) as bioindicator of the soil quality (Standard methods: ISO 17512-1:2008). To accomplish this aim, the main chemical parameters of the substrates were analyzed: moisture, pH, electrical conductivity (EC), ash, organic matter (OM), cation exchange capacity (CEC), total nitrogen (N), total and available phosphorus (P) and organic carbon (Corg). The main nutritional traits (free sugar, phenols, protein content, etc) were determined in plants. The amounts of toxic elements were assessed in plants and substrates. In detail, sixteen polycyclic aromatic hydrocarbons and main polychlorinated biphenyls were analyzed after automated Soxhlet extraction using 1:1 (v/v) acetone/hexane (EPA methods 3541) and quantified by GC-MS. The heavy metal concentrations were analyzed by using atomic absorption spectrophotometer (ISO 11466). For microbiological analysis, the activity of 19 hydrolytic enzymes was assessed by API-ZYM system together with the analysis of total aerobic viable, cellulolytic and spore-forming bacteria. Experimental results showed that biochar was not toxic to biotic soil communities (seeds and earthworms). The chemical analysis of PS lettuce plants indicated that biochar increased EC, OM, total N, Corg, total and available P in PSB and PSCB. However, the highest increments were obtained in PSBC. The chemical analysis of soil growing tomato plants demonstrated that the biochar addition increased EC, OM, Corg, total N and moisture in PSB and RSB; whereas total and available P increased in PSB and RSB, respectively. Again, the highest increments were obtained in RSB. No variations were recorded in Cd, Cr, Co and Pb content between the different treatments. Microbiological analysis confirmed that biochar increased the microbe biomass and the enzymatic activities. Analyses of substrate-microbe-plant system provide an experimental framework that help defining the benefit and toxicity of biochar addition on physical and chemical properties of PS and RS, as well as the interactions with microbial communities.

A review, with 66 refs. on the isolation and structure characterization of bioactive secondary metabolites from marine invertebrates.

Lors de cette conférence, nous présentons les résultats les plus récents obtenus en collaboration avec l'ORSTOM et le CNRS, dans le cadre du programme SMIB; en particulier quelques aspects de la chimie de quatre organismes marins récoltés au large de la Nouvelle Calédonie sont discutés : #Gymnocrinus richeri$, un crinoïde fossile vivant découvert par Bertrand Richer de Forges à 520 m de profondeur; l'étoile de mer #Tremaster novaecaledoniae$, aussi un fossile vivant, récolté à 530 m; deux éponges profondes, #Erylus sp.$ et #Jereicopsis graphidiophora$, cette dernière étant d'un nouveau genre découvert par Claude Lévi du Muséum National d'Histoire Naturelle de Paris. (Résumé d'auteur)

Two novel steroidal glycosides have been isolated from the starfish Gomophia watsoni; they co-occur with one known glycoside and two new polyhydroxysteroids. The structures of the new metabolites, 2,3,4 and 5, were determined on the basis of spectral data. (Résumé d'auteur)

A review about antioxidant activity and biological properties of phytochemical in vegetables and spices (capsicum, laurus, foeniculum).

Tanshinone IIA (TIIA) and cryptotanshinone (CRY) from Salvia miltiorrhiza Bunge were investigated for their inhibitory activity against the cyclooxygenase-2 (COX-2)/microsomal prostaglandin E synthase-1 (mPGES-1)/endothelial prostaglandin 3 (EP3) pathway using in silico, in vitro, in vivo, and ex vivo assays. From the analysis of the docking poses, both diterpenoids were able to interact significantly with COX-2, 5-lipoxygenase (5-LO), platelet-activating factor receptor (PAFR), and mPGES-1. This evidence was further corroborated by data obtained from a cell-free assay, where CRY displayed a significant inhibitory potency against mPGES-1 (IC50 = 1.9 ± 0.4 µM) and 5-LO (IC50 = 7.1 µM), while TIIA showed no relevant inhibition of these targets. This was consistent with their activity to increase mice bleeding time (CRY: 2.44 ± 0.13 min, p ≤ 0.001; TIIA: 2.07 ± 0.17 min p ≤ 0.01) and with the capability to modulate mouse clot retraction (CRY: 0.048 ± 0.011 g, p ≤ 0.01; TIIA: 0.068 ± 0.009 g, p ≤ 0.05). For the first time, our results show that TIIA and, in particular, CRY are able to interact significantly with the key proteins involved not only in the onset of inflammation but also in platelet activity (and hyper-reactivity). Future preclinical and clinical investigations, together with this evidence, could provide the scientific basis to consider these compounds as an alternative therapeutic approach for thrombotic- and thromboembolic-based diseases.

We developed a general HPLC method for the discrimination of (D,L)-monosaccharide components from natural products. The reaction involves the preparation of L-cysteine (3-nitrophenyl) methyl ester hydrochloride, which reacts with aldoses leading to thiazolidine derivatives. Direct HPLC analysis with reversed-phase column and UV detection, discriminated enantiomeric D- and L-monosaccharides in a highly sensitive manner. This method was applied for the determination of the absolute configurations of monosaccharides in the natural poliumoside B, a tetraglycoside obtained from Teucrium polium.

Microalgae cultivation systems fed with wastewater as source of nutrients represents the principal sustainable condition to produce microalgal biomass to be converted conveniently to biofuels. In order to optimize microalgae growth and their lipid content, the effect of light intensity and nutrients load in real wastewater was investigated through batch microalgal cultivation tests. A microalgal polyculture was used as inoculum and grown for 10 days in batch at different conditions of light intensity (i.e. 20, 50 and 100 μmol s−1m−2) and nutrients concentration in wastewater. Experimental results showed that biomass productivity decreased for rich nutrients conditions and increased for high light intensities. The highest lipid mass content (29%) was found for high light intensity condition (100 μmol s−1m−2). Furthermore, microalgae settleability tests, conducted at the end of the cultivation time, resulted in the highest biomass recovery efficiency (72%) for low light intensity and nutrients supply conditions.

Three new furostanol saponins named capsicoside E (1), capsicoside F (2), and capsicoside G (5) were obtained from the seeds of Capsicum annuum L. var. acuminatum along with known oligoglycosides (3, 4, and 6-10). On the basis of chemical and spectroscopic analyses, the structures of these new furostanol oligoglycosides were elucidated as 26-O-beta-D-glucopyranosyl-22-O-methyl-5alpha-furost-25(27)-en-2alpha,3beta,22xi,26-tetraol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (1), 26-O-beta-D-glucopyranosyl-(25R)-5alpha-furost-20(22)-en-2alpha,3beta,26-triol-3-O-beta-D-glucopyranosyl (1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (2), and 26-O-beta-D-gluco-pyranosyl-(25R)-5alpha-furosta-3beta,22xi,26-triol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (5). The isolated saponins showed higher antimicrobial activity against yeasts than against common fungi. Data indicated that the antiyeast activity was related to the combination of the oligosaccharide chain (S1, S2, or S3) with an O-methyl group at R(3) and the presence of a hydroxyl group at the C-2 position.

In the present study, the chemical composition and antioxidant activities of Teucrium polium L. (Lamiaceae) were assessed. Fractionation of methanol extract obtained from the aerial parts of T. polium yielded one new phenylethanoid glycoside, named poliumoside B, together with four known flavonoids, two iridoid glycosides and a known poliumoside. The structures of all of these compounds were elucidated on the basis of spectroscopic data from 1D and 2D NMR experiments and MS spectral analyses. The antioxidant activities of the crude extracts and of the isolated compounds were evaluated through tests such as DPPH radical-scavenging capability, reducing power, xanthine oxidase inhibitory effect and inhibition of linoleic acid peroxidation. The highest antioxidant activity was found in the n-butanol extract, which also contained active polyphenols, thus suggesting that this plant could be used as a source of natural molecules, to provide safe antioxidant additives and nutraceuticals. The structure–activity relationships of the isolated compounds are also discussed.

A new phenolic glycoside ( E )-4-hydroxycinnamyl alcohol 4- O -(2′- O -β- d -apiofuranosyl)(1″ → 2′)-β- d -glucopyranoside ( 1 ) was isolated and identified from Cucumis melo seeds together with benzyl O -β- d -glucopyranoside ( 2 ), 3,29- O -dibenzoylmultiflor-8-en-3α,7β,29-triol ( 3 ) and 3- O - p -amino-benzoyl-29- O -benzoylmultiflor-8-en-3α,7β,29-triol ( 4 ). Their structures were elucidated by extensive NMR experiments including 1 H– 1 H (COSY, TOCSY, ROESY) and 1 H– 13 C (HSQC and HMBC) spectroscopy and chemical evidence. The multiflorane triterpene esters were identified as new melon constituents.

A phytochemical analysis of Aster sedifolius has led to the isolation of three novel triterpenoid saponins, based on an oleane-type skeleton and named astersedifolioside A (1), B (2) and C (3). On the basis of chemical, and 2D NMR and mass spectrometry data, the structures of the new compounds were elucidated as 3-O-[alpha-L-rhamnopyranosyl (I --> 2)-beta-D-glucopyranosyl] echinocystic acid 28-[O-alpha-L-rhamnopyranosyl (I --> 2)-alpha-L-arabinopyranoside] (1), 3-O-[alpha-L-rhamnopyranosyl (1 --> 2)-beta-D-glucopyranosyl] echinocystic acid 28-[O-beta-D-xylopyranosyl (1 --> 4)-O-alpha-L-rhamnopyranosyl (1 --> 2)-alpha(-L-arabinopyranoside] (2) and 3-O-[alpha-L-rhamnopyranosyl (I --> 2)-beta-D-glucopyranosyl (I --> 2)-alpha-D-glucopyranosyl] echinocystic acid 28-[O-beta-D-xylopyranosyl (I 4)-O-alpha-L-rhamnopyranosyl (I --> 2)-alpha-L-arabinopyranoside] (3). The isolated compounds showed antiproliferative effect in KiMol, a transformed thyroid cell line. (C) 2004 Published by Elsevier Ltd.