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The capability of biotransformation of 11 microalgae strains was tested on ethinylestradiol (EE). Seven strains were ineffective whilst Selenastrum capricornutum, Scenedesmus quadricauda, Scenedesmus vacuolatus and Ankistrodesmus braunii biotransformed the substrate. EE was converted by S. capricornutum in three products (ethinylestradiol glucoside, 3-beta-D-glucopyranosyl-2-hydroxyethinylestradiol, and 3-beta-D-glucopyranosyl-6beta-hydroxyethinyl estradiol) in 40%, 5%, and 5% yields, respectively. S. quadricauda transformed EE into 17alpha-ethinyl-1,4-estradien-10,17beta-diol-3-one (12%) and A. braunii transformed EE into 6-alpha-hydroxy-ethinylestradiol (25%). It is noteworthy that EE is converted in 92% yield in ethinylestradiol glucoside by S. capricornutum when using optimal algal density conditions.

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Lansoprazole and omeprazole degrade in water leading to sulfides, benzimidazolones and a red complex material. Degradation is accelerated in acid medium and by solar simulator irradiation. Benzimidazoles, dianilines and pyridines have also been identified.

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The abiotic degradation of iodosulfuron-methyl-ester was investigated under both alkaline and acidic pH conditions in the dark, and results showed it to be a rather stable molecule in neutral or slightly alkaline environments. Photochemical reactions were studied using a high-pressure mercury arc lamp, and results showed that direct phototransformation is possible under normal environmental conditions (lambda > 290 nm). High-performance liquid chromatography (HPLC-UV and HPLC-MS) analyses were used to identify the degradates and to study the kinetics of photodecomposition and hydrolysis. Five main products of iodosulfuron-methyl-ester degradation were tentatively identified, and one of them (4-methoxy-6-methyl-1,3,5-triazin-2-amine) was confirmed using an authentic standard. Among the phototransformation mechanisms, photosubstitution of the iodide atom by a hydroxyl group, photodissociation of the N-S bond, and photoassisted hydrolysis were observed. The quantum efficiencies (multiwavelength quantum yield) of the photodegradation under different conditions were determined, and values of 0.054 +/- 0.02 (pH 9.6), 0.08 +/- 0.02 (pH 7), and 0.044 +/- 0.008 (pH 5.3) were obtained.

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Twenty-four aromatic metabolites belonging to cyanogenins, lignans, flavonoids, and phenolic glycosides were obtained from Sambucus nigra. Structures were determined on the basis of their spectroscopic features. Two compounds have been isolated and identified as (2S)-2-O-beta-D-glucopyranosyl-2-hydroxyphenylacetic acid and benzyl 2-O-beta-D-glucopyranosyl-2,6-dihydroxybenzoate. All the compounds have been assayed on dicotyledons Lactuca sativa (lettuce) and Raphanus sativus (radish) and monocotyledon Allium cepa (onion) to test their stimulatory or inhibitory effects on seed germination and radicle elongation. Cyanogenins have a mainly inhibiting effect while lignans stimulate the growth. Some compounds show different effects on dicotyledons and monocotyledons.

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Crystalline cholest-4-en-3-one undergoes solid-state dimerization by UV radiation to give two ring A - ring A connected dimers. No dimerization occurs in solution. The first dimer, characterized by a cyclobutane ring, is formed by connection of C-2 and C-3 of a moiety with C-5' and C-6' of another moiety, respectively. The latter dimer has a six-membered ketal ring formed by connection of C-2 with C-5' and of O, linked to C-3, with C-3'. The structures have been determined by spectroscopic means. X-ray analysis of title compound evidences the proximity of the axial H-2 of a molecule to the C-4' of a molecule in the upper layer. The transfer of the hydrogen and the connection between C-2 and C-5' might be the driving force of dimerization.

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9,10-Dihydrophenanthrenes and phenanthrenes, mimics of natural compounds with strong antialgal activity, have been synthesized through cross-coupling by zerovalent Ni of 1-(2-iodo-5-methoxy)-phenylethanol or 2-iodo-5-methoxyacetophenone with iodoxylenes. The synthetic compounds had a hydroxyl or a methoxyl group at C-2 and two methyls in the C ring. Assays on the green alga Selenastrum capricornutum showed that all the compounds, except 2-methoxy-5,7-dimethylphenanthrene, caused strong inhibition of algal growth at 10(-4) M. 2-Hydroxy-7,8-dimethyl-9,10-dihydrophenanthrene and 2-methoxy-5,6-dimethylphenanthrene fully inhibited growth at 10(-5) M.

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Twenty-nine free and glucosylated dihydrophenanthrenes and tetrahydropyrenes isolated fromJuncus effusus have been tested against the unicellular green algaSelenastrum capricornutum. The free compounds showed a strong inhibitory activity, while the glucosides were inactive or had a slight stimulating effect on growth. Tetrahydropyrene33, obtained by hydrolysis of the naturalß-glucosides29 and30 or by hemisynthesis from1, is the most active compound, causing 90% inhibition of the growth at 2.5 × 10(-5) M concentration. Synthetic α-glucosides28, 31, and32 showed comparable activity to those of29 and30.

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Ten different strains of unicellular microalgae have been used in the bioconversion of progesterone. Regio and stereoselective reduction and hydroxylation of the title compound were induced. A 9,10-seco derivative was obtained in high yield by using Scenedesmus quadricauda.

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Five new cycloartane glucosides, juncosides I-V, have been isolated from Juncus effusus. The structures have been determined on the basis of chemical and spectroscopic studies.

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Six new oleanane glycosides, ranuncosides I-VI, have been isolated from Hydrocotyle ranunculoides. Their structures have been determined on the basis of chemical and spectroscopic studies.

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Among the substances isolated from ethyl ether extract ofPistia stratiotes L., linoleic acid,γ-linolenic acid, (12R,9Z,13E,15Z)-l2-hydroxy- 9,13,15-octadecatrienoicacid, (9S,10E,12Z,15Z)-9-hydroxy-10,12,15-octadecatrienoic acid, α-asarone, and 24S-ethyl-4,22-cholestadiene-3,6-dione were found to inhibit the growth of some microalgae in solid medium. Toxicity of α-asarone on the growth of sensitive algal strains in liquid medium is discussed.

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The ether extract ofTypha latifolia L. inhibited the growth of some microalgae. Among the substances chromatographically isolated and characterized from the ether extract, three steroids [ß-sitosterol, (20S) 24-methylenlophenol, and stigmast-4-ene-3,6-dione] and three fatty acids [α- linolenic, linoleic, and an unidentified C8∶2] were found to inhibit the growth of some microalgae tested. A selective effect of these substance on blue-green algae (particularly on T 625Synechococcus leopoliensis and on T 1444Anabaena flosaquae) was observed.

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Better synthetic approaches to 2alpha,3beta-dihydroxy-5alpha-cholestane and its ester derivatives, which were hitherto difficult to prepare, are reported. A satisfactory preparation of the desired trans-diequatorial 2alpha,3beta-dibenzoate, starting from the easily available corresponding cis 2alpha,3alpha-diol, has been devised. Finally, the influence of the temperature as well as of the bulkiness of the silver carboxylate on the steric course of the Prevost reaction have also been examined.

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