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1.
Changes in the concentration of tocopherol, monophenols, o-diphenols, squalene, and polyunsaturated fatty acids in olive oil were evaluated during 1 year at various storage conditions. Samples of two different extra virgin olive oil (EOO), produced in Calabria (Italy), were stored in dark and in colorless bottles, filled up completely or to half, in order to simulate the domestic storage conditions. The extent of oxidation or photooxidation was monitored by periodic measurements of peroxide values and the rate of degradation of alpha-tocopherol, o-diphenols, squalene, and polyunsaturated fatty acids. The quantitative analysis of the constituents has been performed by HPLC-DAD, HPLC-MS, and GC-MS. The main changes in the concentrations of the analyzed compounds were associated with the major oxygen level in the half-empty glass bottles. alpha-Tocopherol was the first molecule to be oxidized (-20% after 2 months, -92% after 12 months). Squalene and o-diphenols were protected in the first months by the presence of alpha-tocopherol, and their content decreased significantly only after 6 and 8 months, respectively, in the half-empty bottles. The concentration of polyunsaturated fatty acids remained almost constant during 8 months for all four different storage conditions; their oxidation started when the level of the antioxidants decreased.  相似文献   
2.
A plot study was conducted to quantify long-term (>12 years) impacts of a single biosolids application, and short-term impacts (<2 years) of a repeated application, on semi-arid rangeland soil chemical and microbial parameters. In 2003 and 2004, plots which had received 0, 2.5, 5, 10, 21, or 30 Mg biosolids ha−1 once in 1991 (long-term plots), or again in 2002 (short-term plots), were sampled and analyzed for soil chemical parameters, microbial biovolumes, C and N mineralization activities, Biolog EcoPlate substrate utilization potential, and plant productivity and tissue quality. Repeated applications temporarily exacerbated differences in soil chemical properties among treatments, but after 2 years, soil chemistry trends were similar between short-term and long-term plots. Soils which received a repeated application of 21 or 30 Mg biosolids ha−1 had greater bacterial biovolumes and C and N mineralization activities. In long-term plots, mineralization activities were stimulated only at the highest rate. Biosolids-amended soil communities also utilized Biolog substrates more quickly compared to communities from control plots. Plant biomass increased, whereas plant diversity and plant C/N ratio decreased with increasing application rate for both short- and long-term plots. Infrequent biosolids application had positive ecosystem effects in terms of site management objectives, with relatively low extractable metal levels in soil and greater plant biomass and tissue quality despite reduced species richness.  相似文献   
3.
Two primers, specific for Phytophthora nicotianae (Pn6) and P. citrophthora (Pc2B), were modified to obtain Scorpion primers for real-time identification and detection of both pathogens in citrus nursery soils and roots. Multiplex PCR with dual-labelled fluorogenic probes allowed concurrent identification of both species ofPhytophthora among 150 fungal isolates, including 14 species of Phytophthora. Using P. nicotianaespecific primers a delayed and lower fluorescence increase was also obtained from P. cactorumDNA. However, in separate real-time amplifications, the aspecific increase of fluorescence from P. cactorum was avoided by increasing the annealing temperature. In multiplex PCR, with a series of 10-fold DNA dilutions, the detection limit was 10 pg l-1 for P. nicotianaeand 100 pg l–1 for P. citrophthora, whereas in separate reaction DNA up to 1 pg l-1 was detected for both pathogens.Simple and rapid procedures for direct DNA extraction from soil and roots were utilised to yield DNA whose purity and quality was suitable for PCR assays. By combining these protocols with a double amplification (nested Scorpion-PCR) using primers Ph2-ITS4 amplifying DNA from the main Phytophthora species (first round) and PnB5-Pn6 Scorpion and Pc2B Scorpion-Pc7 (second round), it was possible to achieve real-time detection of P. nicotianaeand P. citrophthora from roots and soil. The degree of sensitivity was similar to that of traditional detection methods based on the use of selective media. The analyses of artificially and naturally infested soil showed a high and significant correlation between the concentration of pathogen propagules and the real-time PCR cycle threshold.  相似文献   
4.
Oxylipins are a large and diverse family of fatty acid derivatives exhibiting different levels of oxidation of the carbon chain. They are involved in many biological functions in mammals, plants and diatoms. In this last group of organisms, they are suggested to play a role in the reproductive failure of copepod predators, showing clear pro-apoptotic effects on newborn nauplii. In this work, these compounds were tested for the ability to induce mitotic arrest in sea urchin embryos. We show for the first time that oxylipins have an increased efficacy in their corresponding methylated form. Natural oxylipins were also used as an inspiration for the rational design and synthesis of stable chemical analogs with apoptotic activity against tumor cell lines. This approach led to the synthesis of the linear C15-ketol (22) that was shown to induce apoptosis in human leukemia U-937 cells. These results are proof of the concept of the use of eco-physiological considerations as a platform to guide the search for novel drug candidates.  相似文献   
5.
Accurate characterization of biomass constituents is a crucial aspect of research in the biotechnological application of natural products. Here we report an efficient, fast and reproducible method for the identification and quantitation of fatty acids and complex lipids (triacylglycerols, glycolipids, phospholipids) in microalgae under investigation for the development of functional health products (probiotics, food ingredients, drugs, etc.) or third generation biofuels. The procedure consists of extraction of the biological matrix by modified Folch method and direct analysis of the resulting material by proton nuclear magnetic resonance (1H NMR). The protocol uses a reference electronic signal as external standard (ERETIC method) and allows assessment of total lipid content, saturation degree and class distribution in both high throughput screening of algal collection and metabolic analysis during genetic or culturing studies. As proof of concept, the methodology was applied to the analysis of three microalgal species (Thalassiosira weissflogii, Cyclotella cryptica and Nannochloropsis salina) which drastically differ for the qualitative and quantitative composition of their fatty acid-based lipids.  相似文献   
6.
Immunotherapy takes advantage of the immune system to prevent, control, and eliminate neoplastic cells. The research in the field has already led to major breakthroughs to treat cancer. In this work, we describe a platform that integrates in vitro bioassays to test the immune response and direct antitumor effects for the preclinical discovery of anticancer candidates. The platform relies on the use of dendritic cells that are professional antigen-presenting cells (APC) able to activate T cells and trigger a primary adaptive immune response. The experimental procedure is based on two phenotypic assays for the selection of chemical leads by both a panel of nine tumor cell lines and growth factor-dependent immature mouse dendritic cells (D1). The positive hits are then validated by a secondary test on human monocyte-derived dendritic cells (MoDCs). The aim of this approach is the selection of potential immunotherapeutic small molecules from natural extracts or chemical libraries.  相似文献   
7.
8.
Sustainable soil management of orchards can have positive effects on both soils and crop yields due to increases in microbial biomass, activity and complexity. The aim of this study was to investigate medium‐term effects (12 yr) of two different management practices termed ‘sustainable’ (ST) and ‘conventional’ (CT) on soil microbial composition and metabolic diversity of a rainfed mature olive orchard in Southern Italy. ST included no‐till, self‐seeding weeds (mainly graminaceous and leguminosae), and mulch derived from olive tree prunings, whilst CT was managed by frequent tillage and included severe pruning with residues removed from the orchard. Microbial analyses were carried out by culture‐dependent methods (microbial cultures and Biolog®). Molecular methods were used to confirm the identification by light microscopy of the isolates of fungi and Streptomyces. Significantly more culturable fungi and bacteria were found in ST than in CT. The number of fungal groups in ST was also significantly greater than in CT. Overall and substrate‐specific Biolog® metabolic diversity indices of microbial communities and soil enzyme activities were greater in ST. The results demonstrate that soil micro‐organisms respond positively to sustainable orchard management characterized by periodic applications of locally derived organic matter. This study confirms the need to encourage farmers with orchards in the Mediterranean basin to practise soil management based on organic matter inputs associated with zero tillage to improve soil functionality.  相似文献   
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10.
In four neighbouring regions of southern Italy, Basilicata, Campania, Apulia and Calabria, pepper and zucchini plants showing Phytophthora blight symptoms, tomato plants with either late blight or buckeye rot symptoms, plants of strawberry showing crown rot symptoms and declining clementine trees with root and fruit rot were examined for Phytophthora infections by means of polymerase chain reaction (PCR) assays, using primers directed to nuclear ribosomal DNA (rDNA) repeat sequences. All diseased plants and trees examined tested positive. The detected fungal-like organisms were differentiated and characterized on the basis of primer specificity as well as through extensive restriction fragment length polymorphism (RFLP) and sequence analysis of PCR-amplified rDNA. Phytophthora capsici was identified in diseased pepper and zucchini plants, P. infestans was identified in tomato with late blight symptoms whereas buckeye rot-affected tomatoes and diseased strawberry plants proved to be infected by P. nicotianae and P. cactorum, respectively. Declining clementine trees were infected with P. citrophthora and P. nicotianae in about the same proportion. Also, thirty-one pure culture-maintained isolates of Phytophthora which had previously been identified in southern Italy by traditional methods but were never examined molecularly, were examined by RFLP and sequence analysis of PCR-amplified nuclear rDNA. Among these, an isolate from gerbera which had previously been identified by traditional methods only at genus level, was assigned to P. tentaculata. For the remaining pure culture-maintained isolates examined, the molecular identification data obtained corresponded with those delineated by traditional methods. Most of the diseases examined were already known to occur in southern Italy but the pathogens were molecularly detected and fully characterized at nuclear rDNA repeat level only from other geographic areas, very often outside Italy. A new disease to southern Italy was the Phytophthora blight of zucchini. This is also the first report on the presence and molecular identification of P. tentaculata from Italy.  相似文献   
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