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1.
Soils from four estuaries of SW Iberian Peninsula, affected by anthropogenic influence (urban, industrial and agricultural activities), were analyzed for the occurrence of a variety of metals and trace elements including Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S and Zn. The soils presented very high levels of salinity (high concentrations of Na, K and Mg), organic matter and, consequently, of C and N concentrations. In contrast, very low values of CaCO3, Ca and P were found. In addition, it should be highlighted that in certain localities (Piedras 1 and 2 and Guadiana in Huelva, Spain, and Ria Formosa, Faro, Portugal) the concentrations of Pb, S and Zn were extremely high, reaching levels of pollution.  相似文献   
2.
Maritime Spatial Planning (MSP) needs to incorporate spatial information on human impacts. As human activities and uses increase in marine and coastal waters around the world, pressures in ecosystems are also increasing, leading to multiple adverse effects on different species and habitats. The European Directive on MSP aims to achieve an integrated approach to marine governance, whilst securing and maintaining the healthy status of marine and coastal waters, in accordance with the Marine Strategy Framework Directive. The latter requires Member States to develop assessments not only on pressures and impacts, but also on the state of the marine environment and then take measures towards reaching a Good Environmental Status by 2020.The Portuguese Maritime Spatial Plan – Plano de Ordenamento do Espaço Marítimo (POEM) was developed between 2009 and 2012. In 2014 a law establishing the Basis for the Spatial Planning and Management of the National Maritime Space was enacted and in 2015 the framework for the elaboration of a new national Maritime Spatial Plan, named Situation Plan, was established. Portugal will face, in the next five years, the challenge of planning and managing its marine space, whilst promoting its sustainable use and protection.This study adapted a cumulative effects assessment model to understand how the impacts from multiple threats affect the marine and coastal ecosystems and, how this information can be used to improve the management process. Information was gathered on intensity and distribution of activities and uses for the Portuguese continental subdivision marine area, quantified and mapped their cumulative impacts in marine ecosystems, and overlapped with the POEM. Results show that impacts are spreading from the coast up to the Contiguous Zone. Higher scores appear in Transitional and Coastal Waters in the north (Viana do Castelo/Figueira da Foz), centre (Peniche/Setúbal) and south (Lagos/Faro). In some areas with higher ranks, statutes of nature conservation are already in place, but potential activities may still occur on top of existing ones. This study shows that the adapted model is a helpful tool to clarify ocean planning, identify areas of potential conflicts among users and support the decision making process.  相似文献   
3.
Eupolauridine, an indenonaphthyridine alkaloid, has been previously reported by us to exhibit antifungal activity. This study describes the synthesis of new alkyl and benzyl naphthyridinium/pyridinium analogs of eupolauridine as potential antifungal agents. A majority of the analogs exhibited antifungal activity against opportunistic pathogens such as Candida albicans and Cryptococcus neoformans. Several of them were also effective against bacteria (Staphylococcus aureus, MRS, Pseudomonas and Mycobacterium) and the malaria parasite (Plasmodium falciparum) to variable extents. A number of analogs were also cytotoxic to human cancer cell lines.  相似文献   
4.
The first report of 1′-homo-N-1,2,3-triazol-bicyclic carbonucleosides (7a and 7b) is described herein. Azide-enolate (3+2) cycloaddition afforded the synthesis of this novel type of compound. Antifungal activity was evaluated in vitro against four filamentous fungi (Aspergillus fumigatus, Trichosporon cutaneum, Rhizopus oryzae and Mucor hiemalis) as well as nine species of Candida spp. as yeast specimens. These pre-clinical studies suggest that compounds 7a and 7b are promising candidates for complementary biological studies due to their good activity against Candida spp.  相似文献   
5.
Previous studies have indicated that most trypsin inhibitor-like cysteine-rich domain (TIL)-type protease inhibitors, which contain a single TIL domain with ten conserved cysteines, inhibit cathepsin, trypsin, chymotrypsin, or elastase. Our recent findings suggest that Cys2nd and Cys6th were lost from the TIL domain of the fungal-resistance factors in Bombyx mori, BmSPI38 and BmSPI39, which inhibit microbial proteases and the germination of Beauveria bassiana conidia. To reveal the significance of these two missing cysteines in relation to the structure and function of TIL-type protease inhibitors in B. mori, cysteines were introduced at these two positions (D36 and L56 in BmSPI38, D38 and L58 in BmSPI39) by site-directed mutagenesis. The homology structure model of TIL domain of the wild-type and mutated form of BmSPI39 showed that two cysteine mutations may cause incorrect disulfide bond formation of B. mori TIL-type protease inhibitors. The results of Far-UV circular dichroism (CD) spectra indicated that both the wild-type and mutated form of BmSPI39 harbored predominantly random coil structures, and had slightly different secondary structure compositions. SDS-PAGE and Western blotting analysis showed that cysteine mutations affected the multimerization states and electrophoretic mobility of BmSPI38 and BmSPI39. Activity staining and protease inhibition assays showed that the introduction of cysteine mutations dramaticly reduced the activity of inhibitors against microbial proteases, such as subtilisin A from Bacillus licheniformis, protease K from Engyodontium album, protease from Aspergillus melleus. We also systematically analyzed the key residue sites, which may greatly influence the specificity and potency of TIL-type protease inhibitors. We found that the two missing cysteines in B. mori TIL-type protease inhibitors might be crucial for their inhibitory activities against microbial proteases. The genetic engineering of TIL-type protease inhibitors may be applied in both health care and agricultural industries, and could lead to new methods for breeding fungus-resistant transgenic crops and antifungal transgenic silkworm strains.  相似文献   
6.
Phytochmical investigation of roots of Actinidia chinensisPlanch . led to the isolation triterpenoids 1 – 16 , including a new compound 2α,3α,23,24‐tetrahydroxyursa‐12,20(30)‐dien‐28‐oic acid ( 1 ). Their structures were identified on the basis of spectroscopic analysis, including 1D‐ and 2D‐NMR, HR‐ESI mass spectrometry, and by comparison with the literatures. The cytotoxicities of triterpenoids 1 – 16 against a panel of cultured human cancer cell lines (HepG2, A549, MCF‐7, SK‐OV‐3, and HeLa) were evaluated. The new compound 1 exhibited moderate antitumor activities with IC50 values of 19.62 ± 0.81, 18.86 ± 1.56, 45.94 ± 3.62, 62.41 ± 2.29, and 28.74 ± 1.07 μm , respectively. The experiment data might be available to explain the use of roots of A. chinensis to treat various cancers in traditional Chinese medicine.  相似文献   
7.
The behaviour of summer and autumn winged forms of the black bean aphid, Aphis fabae Scopoli (Homoptera: Aphididae), was compared on two plants utilized at different stages of the insect’s life cycle. Adult autumn migrants (gynoparae) are monophagous, colonizing spindle (Euonymus europaeus), whereas polyphagous summer winged aphids (alate virginoparae) are associated with a variety of herbaceous plants, including broad bean (Vicia faba). When aphids from a single clone were given access to a spindle leaf and a bean seedling in choice tests, many virginoparae settled and larviposited on both plant species over 24 h. By contrast, gynoparae showed a clear preference for spindle, with 93.5% of settled adults and 98.3% of larvae on this plant species. Close‐up video monitoring showed that gynoparae discriminated beans from spindle within a 5‐min period, whereas virginoparae behaved similarly on both plant species. For gynoparae, the major behavioural difference on the two plants appeared after a brief (epidermal) stylet penetration, with many insects taking flight within a few seconds of stylet withdrawal from bean. Factors detected during stylet insertion by gynoparae must therefore inhibit take‐off on spindle. Electrical recording experiments showed that aphids often punctured a cell membrane during brief probes on both plant species, and intracellular stylet activities always included a waveform associated with ingestion. When gynoparae puncture spindle cells their behaviour is probably modified by intracellular metabolites detected via gustation of ingested epidermal cell sap. These cues may inhibit the take‐off reflex which otherwise follows probing.  相似文献   
8.
V. Pietsch 《Plant Ecology》1985,59(1-3):97-109
On the basis of three selected examples chorological phenomena in waterplant communities of central, east and southern Europe are represented. Species of the Atlantic-oceanic floral element of the order Juncetalia bulbosi, like Pilularia globulifera, Eleocharis multicaulis and Deschampsia setacea are growing in markedly secondary sites near their eastern border, i.e. in the Lusatian district of central Europe, especially in sand, gravel and clay pits as well as in residue lakes of opencast mines. As a result of intensive recent human activities numerous new sites are being established now causing an expansion of their distribution area. With decreasing oceanity from the central part to the eastern border of the area a change in the floristic-sociological structure of the relevant plant communities and in the hydrochemical composition of the respective water bodies takes place. In western Europe the species grow in soft water poor in minerals, in the eastern part (central Europe) in mineral-rich, hard water with calcium and sulphate.At present Ceratophyllum submersum has a high frequency in the northeastern area in Mecklenburg. The sites are morainic lakes (kettle holes) and small waters and ponds near settlements, which are enriched in minerals and nitrales in consequence of the intensive agricultural use of inorganic fertilizers. Moreover the waters are alkaline and rich in minerals, especially bicarbonate and possess a high range of total hardness. The example of eight different sites of Aldrovanda vesiculosa illustrates a striking change of its diagnostic value in its disjunct north-south distribution. In the northern part of central Europe Aldrovanda is found in the communities of the Utricularietea intermedio-minoris, both in waters with a low acidity rich in sulphate and in alkaline waters rich in bicarbonate (Sphagno-Utricularion and Scorpidio-Utricularion respectively). In southern central Europe and in southeastern Europe Aldrovanda occurs in Lemnetea and Potametea communities. In northeastern Poland Aldrovanda is found together with Hydrilla verticillata, Chara mentosa, Myriophyllum verticillatum and Scorpidium scorpioides.
Die Sippennomenklatur richtet sich nach Rothmaler et al. (1970).  相似文献   
9.
Streptomyces sp. NK 1057 produced four extracellular chitinases. Two (62 and 48 kDa) were endochitinaseswhile the other two (35 and 28 kDa) had chitobiosidaseactivity. Chi62 was produced in early growth phase whereas the other three were produced later. Chi48 was optimally active at pH 4.0 and 60 °C whereas Chi35 was optimally active at pH 6.0 and 40 °C. Both the enzymes had fairly good pH and temperature stability up to 50 °C, with Chi48 being more thermostable than Chi35. Chi48 was significantly inhibited by N-acetylglucosaminebut not by Hg2+ and the reverse was true for Chi35. Chi48 and Chi35 had isoelectric points of 5.1 and 6.0 and the N-terminal amino acid sequence of Chi35 determined uptofour amino acids, was Gln–Ser–Pro– Gly. Chi62 and Chi48 were able to inhibit the germination of Fusariumoxysporum spores by 57.4 and 61.2% respectively whereas; Chi35 and Chi28 did so by only 14.1 and 3.8%, suggesting endochitinaseto possess antifungal activity. Only Chi28 exhibited a lytic activity, 0.022 U ml–1, towards Micrococcus lysodeikticus cells.  相似文献   
10.
Seasonal variations in the chemical composition of leaves fromAgastache rugosa were analyzed by gas chromatography-mass spectrometry (GC-MS). Phytotoxic and antimicrobial activities of its essential oil were investigated by characterizing 31 components, primarily methylchavicol (80.24%),dl-limonene (3.50%), linalool (4.23%), 5-methyl-2-(1-methylethylidene)-cyclohexanone (3.84%), and β-caryophyllene (2.39%). The contents of most of these chemical constituents varied significantly (P<0.05) over time, with the highest oil yield being early in the growing season (May). Their phytotoxic effects on the seed germination ofMajorana hortensis, Trifolium repens, Rudbeckia hirta, Chrysanthemum zawadskii var.latilobum, Melissa officinalis,Taraxacum platycarpum, andTagetes patula also were determined. These oils partially or completely inhibited germination, and prevented the growth of radicles and hypocotyls. Results of antimicrobial testing showed that the oils also entirely blocked the growth of four microorganisms (Staphylococcus aureus sub.aures, Escherichia coli, Salmonella enteritidis, andPseudomonas aeruginosa). These inhibitory effects might depend on the activity of methylchavicol, a main compound inA. rugosa.  相似文献   
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