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Nine 9,10-dihydrophenanthrenes, three phenanthrenes and a related pyrene have been isolated from the wetland plant Juncus acutus. The structures have been attributed by means of their spectral data and chemical correlation. 5-(1-Ethoxy-ethyl)-2-hydroxy-7-methoxy-1,8-dimethyl-9,10-dihydrophenanthrene and 5-(1-phytoxy-ethyl)-2-hydroxy-7-methoxy-1,8-dimethyl-9, 10-dihydrophenanthrene, 2,7-dihydroxy-1-methyl-5-vinylphenanthrene, 2,7-dimethoxy-1,6-dimethyl-5-vinylphenanthrene and 2,7-dihydroxy-1,6-dimethylpyrene are described for the first time. Many of the compounds showed in vitro phytotoxicity against Selenastrum capricornutum, a microalga used in aquatic tests. © 2002 Elsevier Science Ltd. All rights reserved.

In a study of the allelochemical interaction between the wetland plant Juncus acutus and microalgae an unusual dimeric 9,10-dihydrophenanthrenoid has been isolated. The structure has been determined on the basis of its spectroscopic properties. © 2002 Elsevier Science Ltd. All rights reserved.

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-β-D-glucopyranosyl-2-hydroxyphenylacetic acid and benzyl 2-O-β-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. © 2001 Elsevier Science Ltd. All rights reserved.

Two new sterols have been isolated from the aquatic plant Ruppia maritima and their structures were established as (24R) ergosta-8,22-diene-3 beta,6 beta,7 alpha-triol (1) and (24R) ergosta-8(14),22-diene-3 beta,6 beta,7 alpha-triol (2) on the basis of spectroscopic analysis.

Sixfurano-ent-labdanes,19-acetoxy-15,16-epoxy-8(17),13(16),14-ent-labdatrien-20-al,15,16-epoxy-12-oxo-8(17),13(16),14-ent-lab-datrien-20,19-olide,12(S)-hydroxy-15,16-epoxy-8(17),13(16),14-ent-labdatrien-20,19-olide,10a,19-dihydroxy-15,16-epoxy-8(17),13(16),14-nor-ent-labdatriene, 19,20-dihydroxy-15,16-epoxy-8(17),13(16),14-ent-labdatriene, 15,16-epoxy-12-oxo-8(17),13(16),14-ent-labdatrien-19,20-olide,wereisolated,togetherwiththeknownpotamogetonin,fromtheaquaticplantPotamogeton natans.Theirstructuresweredeterminedonthebasisoftheirchemicalandspectraldata.ThecompoundsshowedinvitrophytotoxicityagainstRaphidocelis subcapitata,amicroalgausedinaquatictests.# 2001ElsevierScienceLtd.Allrightsreserved. Keywords: Potamogeton natans;Potamogetonaceae;Raphidocelis subcapitata;ent-Labdanes;Furano-diterpenes;Antialgalactivity;Spectroscopicanalysis 1. IntroductionChemical interactions between aquatic plants andmicroalgaeplayanimportantroleinaquaticecosystemssincetheproductionofmetabolitesbythemacrophytesmightcontrolthealgalgrowth(Fitzgerald,1969).Has-lerandJones(1949)observedthatthealgalpopulationdecreasedwhenplantsbelongingtothePotamogetona-ceaewerepresentintheaquaticsystems.Theabilityofsomenaturalproductstoinhibittheinvitrodevelop-mentofthemicroalgaehasbeenreportedcopiously(DellaGrecaetal.,1996andref.cit.)andinapreviouspaperweshowedthatbioactiveproductsisolatedfromPistia stratiotes arereleasedintotheenvironment(Del-laGrecaetal.,1999).Recently we investigated Potamogeton natans,afreshwater Potamogetonacea, distributed throughouttheMediterraneanbasin(Cangianoetal.,2001).Thephytochemicalstudyhasalreadyledtotheisolationofseveralditerpenelactones,someofthemshowingahighantialgalactivity.2. Results and discussionInpursuingthechemicalinvestigationofP. natans,weisolatedthepotamogetonin(1)(Smithetal.,1976)andsixnewfuranoident-labdanes2–7,identifiedbytheirspectroscopicfeatures.Spectraldataofcompound1 wereingoodagreementwiththoseoftherevisedstructureofpotamogetonin(HasegawaandHirose,1983),butthereweresomedif-ferencesinthechemicalshiftassignments.Ourassign-ments,basedon2DNMRexperiments(H–HCOSY,DEPT,HMBC,HMQC,andNOESY),arereportedinTable 1. The methylene signals at 36.0 and 41.8,ascribedtoC-3andC-1,aswellasthoseat 23.7and25.7,ascribedtoC-11andC-12,wereexchangedonthebasisoftheHMBCexperiment.Infactthesignalat36.1,showinginteractionwiththeH-2at 1.70,wasattributedtotheC-1,whilethesignalat 41.2,corre-latedwiththeH-1,H-18andH-19,wasattributedtotheC-3.Thesamespectrumshowedtheinteractionofthecarbonat 23.8withtheH-11,H-14andH-16sig-nalsandofthecarbonat 25.8withtheH-9andH-12.TheseobservationsareinagreementwiththeexchangeofthecarbonassignmentsatC-11andC-12.The EI mass spectrum of compound 2 showed amolecular ion at m/z 358, which, together with the

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.

Two new aromatic compounds have been isolated from the reverse osmosis fraction of the olive mill waste-waters and identified as C6-C2 dimers on the basis of their physical features.

Three unusual cyanohydrins, which might be formed by oxidative cleavage of cyanogenins, have been isolated from Sambucus nigra. The structures of the compounds have been defined on the basis of spectroscopic features and by chemical degradation. Unlike cyanogenins the title compounds do not have phytotoxic effects and might be involved in the detoxification process of the plant. © 2000 Elsevier Science Ltd.

Seven ent-labdane diterpenes, have been isolated from Ruppia maritima. The structures 15,16-epoxy-ent-labda-8(17),13(16),14trien- 19-al; 15,16-epoxy-ent-labda-8 (17), 13(16), 14-trien- 19-ol acetate; methyl 15,16-epoxy- 12-oxo-ent-labda-8 (17), 13 (16), 14-trien-19-oate; 15,16-epoxy-ent-labd-8 (17), 13E-dien- 15-ol and 13-oxo- 15,16-bis-nor-ent-labd-8 (17)-ene have been assigned to the five new compounds by spectroscopic means and chemical correlations. The phytotoxicity of the diterpenes has been assessed using the alga Selenastrum capricornutum as organism test. (C) 2000 Elsevier Science Ltd.

Seven new minor dihydrophenanthrenes have been isolated from Juncus effusus L. Structures have been defined by spectroscopic means. An antialgal assay, using the green alga Selenastrum capricornutum, showed good activity for six of them. The presence of both polar and nonpolar substituents in these molecules seems to be important for the bioactivity.

Exogenus prednisolone is biotransformed in cultures of the green alga T76 Scenedesmus quadricauda in two main bioproducts, which have been purified by chromatographic processes and identified by spectroscopic means. The first compound is the 5α-hydroxyderivative of prednisolone and might be formed by a simple hydration of the Δ 4 double bond. The latter rises from a complex rearrangement. It is rather unstable and undergoes oxidation by atmospheric oxygen to a hydroperoxide which slowly decays to the corresponding hydroxyderivative.

Twenty-nine free and glucosylated dihydrophenanthrenes and tetrahydropyrenes isolated from Juncus effusus have been tested against the unicellular green alga Selenastrum capricornutum. The free compounds showed a strong inhibitory activity, while the glucosides were inactive or had a slight stimulating effect on growth. Tetrahydropyrene 33, obtained by hydrolysis of the natural β-glucosides 29 and 30 or by hemisynthesis from 1, is the most active compound, causing 90% inhibition of the growth at 2.5 × 10-5 M concentration. Synthetic α-glucosides 28, 31, and 32 showed comparable activity to those of 29 and 30. © 1996 Plenum Publishing Corporation.

2β-Hydroxyprogesterone, 6β-hydroxyprogesterone, 9α-hydroxyprogesterone, 14α-hydroxyprogesterone, 16α-hydroxyprogesterone and 21-hydroxyprogesterone are the main bioproducts in the progesterone bioconversion by axenic cultures of Chlorella emersonii C211-8h. After 30 days 6β,9α-dihydroxyprogesterone, 6β,21-dihydroxyprogesterone and 16α,21-dihydroxyprogesterone are also formed. In acid conditions the reaction is slower and 2β-hydroxyprogesterone and 16α-hydroxyprogesterone have not been found among the bioproducts. In hyperhaline conditions the yields are generally lower and testololactone is also formed. Copyright © 1996 Elsevier Science Ltd. All rights reserved.

Exogenus 17β-hydroxy-17α-methyl-androsta-1,4-dien-3-one and androsta-1,4-diene-3,17-dione are biotransformed by the green alga T76 Scenedesmus quadricauda . The bioproducts have been isolated by chromatographic processes and identified on the basis of their spectroscopic features. Hydration of the Δ 4 double bond may justify the presence of the epimeric 5-hydroxyderivatives while rather complex skeleton rearrangements are involved in the formation of the remaining products.

Adrenosterone is reduced to 11-ketotestosterone by cultures of microalga Scenedesmus quadricauda. The best bioconversion yields (62%) were obtained in cultures containing 3×106 cells/mL of alga and 100 mg of adrenosterone in 400 mL of medium after 10 days at 24°C with a photoperiod light - dark 16:8 h.

Four 9,10-dihydrophenanthrene glucosides have been isolated from Juncus effusus and their structures confirmed on spectroscopic grounds and by semisynthesis. The results of a cytotoxic assay are also reported. © 1995, Taylor & Francis Group, LLC. All rights reserved.

Two tetrahydropyrene glucosides have been isolated from Juncus effuses and their structures determined by spectroscopic analysis and hemisynthesis. © 1995, Taylor & Francis Group, LLC. All rights reserved.

Incremental sheet forming is a technique that allows locally deforming a sheet by means of a movable punch. Even if it requires longer forming time and higher part geometrical tolerances with respect to traditional sheet forming techniques, it does not need dedicated devices and its accuracy can be improved adopting low cost full or partial dies. For these reasons, it results to a flexible technology and economically suitable for low volume batch productions such as pre-series, prototypes or high customised parts. These characteristics well fit with prosthesis manufacturing where each part is a unique product, indeed its geometry needs to meet the patient’s physical characteristics. In the present paper, titanium ISF formed parts will be studied, in particular surface anodising pre-treatment effects on part finishing and biocompatibility are investigated.

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. © 1994.

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. © 1994.

A new cycloartanelactone glucoside, Juncoside I, has been isolated from Juncus effusus anM its structure has been determined by chemical and spectroscopic studies.Key Words. Juncus effusus,Juncaceae, cycloartane glucoside, 3j3-hydroxy-cycloart-24Z-ene-22(S)—»26 lactone, Juncoside I. © 1994 Harwood Academic Publishers GmbH.

Three new triterpenes, i.e. 3-oxo-15α,16α,21β,22α,28-pentahydroxy-Δ1,12-oleanane, 3-oxo-15α,16α,21β, 22α,28-pentahydroxy-Δ12-oleanane and 17,22-seco-3-oxo-22,23-dihydroxy-Δ12,16-oleanonic acid, have been isolated from Hydrocotyle ranunculoides. The structures have been attributed on the basis of their physical features.

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.

A novel dihydrodibenzoxepin has been isolated from Juncus effusus . Its structure, 2, 8-dihydroxy-1,7-dimethyl-6-vinyl-10,11-dihydro-dibenz[b,f] oxepin, has been defined on the basis of spectroscopic data. A preliminary brine shrimp lethality assay showed that the compound was cytotoxic.

Thirteen natural and synthetic phenylpropanoids as well as coumarin (2×104M) were tested for their biological activity on radish germination and subsequent root growth in light and darkness. Coumarin was the most potent inhibitor. With some exceptions, phenylpropanoids with a carboxylic group in the side chain inhibited root growth. Coumarin was formed spontaneously by photooxidation of 2-hydroxycinnamic acid. Microscopic observations of root treated with coumarin suggest that this substance inhibits the elongation of cells of the differentiating zone of the root. © 1993 Plenum Publishing Corporation.

Antioxidant capacity of the aqueous extract of Malva sylvestris was measured by its ability to scavenge the DPPH and superoxide anion radicals and to induce the formation of a phosphomolybdenum complex. Analysis of the extract, carried out by different chromatographic techniques, led to the isolation of eleven compounds: 4-hydroxybenzoic acid, 4-methoxybenzoic acid, 4-hydroxy-3-methoxybenzoic acid, 4-hydroxycinnamic acid, ferulic acid, methyl 2-hydroxydihydrocinnamate, scopoletin, N-trans-feruloyl tyramine, a sesquiterpene, (3 R,7 E)-3-hydroxy-5,7-megastigmadien-9-one, and (10 E,15 Z)-9,12,13-trihydroxyoctadeca-10,15-dienoic acid. The antioxidant activities of all these compounds are reported.

Twenty-four different strains of unicellular algae have been used in the bioconversion of 5α-androstane-3,17-dione. 5 α -androstane-3,17-dione has been bioconverted by twenty-four microalgae The activity of algae seems to be species-specific. Reducted, hydroxylated or more unsaturated steroids have been isolated from the cultures.

Scenedesmus quadricauda (1.5 x 10 cells/ml) grown in myxotrophic conditions reduced in good yields (>63%) exogenous adrenosterone to 11-ketotestosterone. Cultures preadapted on glucose, saccharose or starch (10 mg/l) biotransformed about 80% of adrenosterone (100 mg/l) in seven days. Almost quantitative yields of bioconversion were afforded at higher algal biomass.

In recent years, the ongoing need for novel pharmaceuticals to be introduced in human medicine has substantially benefited from the widespread research activity on the role of bioactive microbial compounds involved in the regulation of interactions with other organisms. A good example is represented by 3-O-methylfunicone, a benzo-γ-pyrone metabolite at first characterized on account of the antifungal aptitude of the producing strain, which has later become more valuable for its antiproliferative and pro-apoptotic properties resulting in a series of studies on human tumor cell lines. An overview of aspects concerning molecular structure, sources, and biological properties of this compound is offered in the present paper.

A new cyanogenic glycoside, 2S-β-D-apio-D-furanosyl-(1→rightarrow2)-β-D-glucopyranosylmandelonitrile, has been isolated from the leaves of Sambucus nigra along with the already known sambunigrin, prunasin, holocalin and the acetyl derivative of the latter. The structures were elucidated by chemical and physical methods.

Eight aromatic monoglycerides and four aromatic diglycerides have been isolated from J. effusus and their structures have been defined by spectroscopic means. Some of the compounds have reasonable antialgal activity on Selenastrum capricornutum.

Olive oil mill wastewater (OMW) was tested for phytotoxicity on seed germination and seedling growth of radish and wheat. The most potent inhibition was observed with the reverse osmosis fraction, from this, 17 polyphenols with molecular weight less than 300 Daltons were isolated by chromatographic processes and identified on the basis of their spectroscopic features. In seed bioassays, the inhibitory activity of each polyphenol was much lower than that observed for the original fraction and the mixture of the pure 17 polyphenols present in reverse osmosis fraction had less effect on seed germination. Thus, OMW phytotoxicity could be due to a synergic action of polyphenols with other unidentified substances present in the wastewater.

The structure (3S,5R,6S,7E,9R)-3-hydroxy-5,6-epoxy-β-ionyl-3–0-β-D-glucopyranoside has been attributed to stratioside I, the major component of the methanolic extract of Pistia stratiotes on the basis of its spectroscopic features and by analysis using the Mosher method. © 1995, Taylor & Francis Group, LLC. All rights reserved.

The structure (3S,5R,6R,7E,9R)-3,5,6-trihydroxy-β-ionyl-3-O-β-D-glucopyranoside has been attributed to stratioside II, a component of the methanolic extract of Pistia stratiotes, on the basis of its spectroscopic features and by chemical correlation.

In this investigation the phytochemical study of chlorophyll derivatives from leaf extract of Petrorhagia velutina, a eurimediterranean plant species typical of macchia vegetation is reported. A new pheophorbide, as well as nine other chlorophyll derivatives were isolated and their structures determined predominantly based on 1D and 2D NMR methods. The phytotoxicity against Raphanus sativus L. was evaluated. A significant photoinduced phytotoxicity was evident for both germination and root elongation.

L’overtourism riconfigura gli spazi della città generando negli abitanti disagio e conflittualità. Su molteplici piani: il diritto all’abitare negato dalla pressione immobiliare nel centro storico e dalla diffusione degli affitti brevi; la svendita del patrimonio pubblico e la sottrazione degli spazi comuni; la mercificazione dell’arte e della cultura; la proliferazione della precarietà lavorativa e del lavoro nero; la compromissione della salubrità degli ambienti di vita e la previsione di nuove infrastrutture indispensabili ai globe trotters (aeroporto, Tav ecc.); il depotenziamento dell’urbanistica e la valorizzazione della rendita; il securitarismo, il decoro e l’obliterazione delle fasce sociali più deboli. La fragilità del modello economico, come dimostrano gli articoli raccolti nel libro che introduciamo, era evidente prima del confinamento e della crisi da Covid-19. La pandemia ha poi messo a nudo e reso evidenti anche al grande pubblico i rischi della dipendenza da turismo globale.

It has been demonstrated [1, 2, 3] that a central bulb placed between the demihulls of a catamaran hull reduces its vertical motions and, partly, its resistance. Previous investigations made by the Author regarded a fast catamaran hull (FN : 0.4 – 0.8). with wedge hull lines and central bulbs placed in different longitudinal and vertical positions. In this paper a new catamaran hull, with faired lines, has been examined on a velocity interval defined by FN : 0.2 – 0.6. A 1:19 scale model was built and tested in resistance and seakeeping tests in regular waves at the towing of Trieste University. The original model without bulbs and in three different bulb configurations has been tested and examined. The results obtained outline the efficiency of these solutions, to improve the seakeeping criterion of catamaran hulls, without reducing their speed, although the bulb efficiency is more effective at higher speeds, close to FN = 0.6.

A method for estimating the wave resistance in planing and semi-planing hulls will be presented. This prediction method calculates the wave resistance from a distribution of surfaces pressures acting over the free water surface and uses the calculation methods, currently applied for the ACV (air-cushion vehicle). Starting from an original paper by G.E. Gadd [1], in which the Author calculated the far field wave pattern for fast boats, the wave resistance is calculated for high speed vehicles by assuming an appropriate hull pressure distribution; then a practical application is presented.

The wave making generated by motorboats and speedy crafts in the canals and lagoon of Venice, due to traffic increase and to the extreme speeds of these crafts, represents a threat for the cultural and architectural heritage of the town. The Municipal Administration of Venice has set up a specific Committee, named “Committee for Wave Motion Research”, to examine the causes and to suggest possible remedies. One of the investigations promoted by the Committee was to measure the wave components, created by five boat models. These measures were performed at the D.I.N.M.A. Department of the University of Trieste and some of the results obtained are reported here. A critical analysis of these data permits a better evaluation of the wave making dangerousness of five boats.