Phenylalanine ammonia‐lyase and phenolic compounds in leaves and fruits of Olea europaea L. cv. Picual during ripening

BACKGROUND: The kinetic and molecular properties of phenylalanine ammonia‐lyase (PAL) in leaves and fruit of the olive tree (Picual variety) have been studied during the seasonal process of fruit maturation. The concentrations of total phenolic compounds, oleuropein, hydroxytyrosol and tyrosol, have also been determined. This study has been made in rainfed 30‐year‐old olive trees in Jaén, Spain, cultivated by the traditional method. RESULTS: PAL specific activity was assayed and hyperbolic kinetics were observed in both organs. The K_m value for L ‐Phe was 0.22 mmol L^?1 in leaf and 0.26 mmol L^?1 in fruit. In leaf, the highest PAL specific activity was found in the stage prior to veraison. By immunoblot, a PAL‐immunoreactive 75 kDa polypeptide was detected in leaf and fruit. In leaf, the level of this protein progressively rose until the last stages of ripening at the same time that total phenols increased. In fruit, PAL activity and protein change as in two series coinciding with different fruit‐maturation period. By immunohistochemistry under light microscopy, PAL was located in the epidermis and parenchyma cells of leaf and fruit. CONCLUSION: These results demonstrate the involvement and regulation of PAL during fruit ripening of olive, cv. Picual. Copyright © 2008 Society of Chemical Industry     

Identification of Exosomal MicroRNA Signature by Liquid Biopsy in Hereditary Hemorrhagic Telangiectasia Patients

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant vascular dysplasia characterized by epistaxis, mucocutaneous telangiectases, and arteriovenous malformations (AVM) in the visceral organs. The diagnosis of HHT is based on clinical Curaçao criteria, which show limited sensitivity in children and young patients. Here, we carried out a liquid biopsy by which we isolated total RNA from plasma exosome samples. A cohort of 15 HHT type 1 patients, 15 HHT type 2 patients, and 10 healthy relatives were analyzed. Upon gene expression data processing and normalization, a statistical analysis was performed to explore similarities in microRNA expression patterns among samples and detect differentially expressed microRNAs between HHT samples and the control group. We found a disease-associated molecular fingerprint of 35 miRNAs over-represented in HHT vs. controls, with eight being specific for HHT1 and 11 for HHT2; we also found 30 under-represented, including nine distinct for HHT1 and nine for HHT2. The analysis of the receiver operating characteristic (ROC) curves showed that eight miRNAs had good (AUC > 75%) or excellent (AUC > 90%) diagnosis value for HHT and even for type HHT1 and HHT2. In addition, we identified the cellular origin of these miRNAs among the cell types involved in the vascular malformations. Interestingly, we found that only some of them were incorporated into exosomes, which suggests a key functional role of these exosomal miRNAs in the pathophysiology of HHT.     

Cell wall-modifying enzymes and firmness loss in ripening ‘Golden Reinders’ apples: A comparison between calcium dips and ULO storage

Calcium treatment and storage under ultra-low oxygen (ULO) conditions are common post-harvest practices aimed at delaying ripening-related softening of apple (Malus × domestica Borkh.) fruit, but the biochemical mechanisms underlying these effects have not been determined conclusively to date. In this study, commercially mature ‘Golden Reinders’ apples were dipped in 2% calcium chloride prior to storage at 1 °C and 92% RH under either regular air or ultra-low oxygen (ULO; 1kPa O₂:2kPa CO₂) for 19 or 31 weeks, and kept thereafter at 20 °C for 0, 7 or 14 days in order to simulate the usual marketing time. Cell wall composition and cell wall-modifying enzyme activities were determined in relation to fruit firmness. ULO-storage and calcium dips were effective for firmness preservation, seemingly due to decreased pectin solubilisation. β-Galactosidase, α-l-arabinofuranosidase and pectate lyase activities were correlated positively with firmness loss of ‘Golden Reinders’ fruit after storage.     

Water Management in Integrated Service Systems: Accounting for Water Flows in Urban Areas

This article focuses on studying the natural and artificial water flows of the service sector from an industrial ecology perspective. The purpose is to determine, in the area under study, the water consumption of the service sector and the most water demanding services in global and relative terms, total water consumption per year and liters per user per year (Lpu) respectively, as well as the existing and potential water flow interrelations among service facilities to reduce their water consumption. Finally we propose measures for water consumption minimization, recycling and reusability based on the results of the diagnosis. The analyzed system is Montjuïc Urban Park (Barcelona, Spain), where the economic activity is based on the service sector (about 200 service facilities and no industrial activities). In the individual study of services we found an average consumption of 75 Lpu, with a large range in the water consumption by service types (between 17 and 156 Lpu), and between facilities of the same service type (51 and 155 Lpu). These results indicate a high level and low regulation of water consumption among the service facilities. In the study of the interrelations between the services we found that a high potential for hydrological saving exists in the system (equivalent to 50% of the potable water inflow from the supply network). The results indicate a lack of ecosystemic and synergic vision in the service sector. Interrelations among water flows have to be established, by means of rainwater collection and the reuse of water flows from swimming pools and ornamental fountains. The article proposes the application of industrial ecology methods to improve water management inside Montjuïc Urban Park and, in general, within any system where the service sector is the main economic activity.     

Diversity of Weissella viridescens strains associated with "Morcilla de Burgos"

Unidentified heterofermentative lactic acid bacterium (LAB) isolates detected earlier in vacuum or modified atmosphere (MA) packaged "Morcilla de Burgos", a Spanish cooked meat product, were identified in the present study. In the previous study, these strains had been studied by numerical analysis of HindIII RFLP- and phenotyping. However, neither of these methods had resulted in species identification. Even these unknown strains clustered together in the numerical analysis of the RFLP patterns, none of the typically meat-associated LAB type strains had clustered together with them. The phenotyping was not more useful; according to the criteria used these strains with similar HindIII ribopatterns should have been divided into four different species in three different genera. To establish the taxonomic position of these isolates, 16S rRNA gene sequence analysis, numerical analysis of EcoRI and HindIII ribopatterns, and DNA-DNA hybridization experiments were done. The 16S rRNA genes sequences of three isolates possessed the highest similarities with the corresponding sequences of Weissella species and in the phylogenetic analysis Weissella viridescens was their closest phylogenetic neighbor. However, in the numerical analysis of either HindIII or EcoRI ribopatterns the W. viridescens type strain did not cluster with these isolates. Nevertheless, the high (from 75% to 83%) DNA-DNA reassociation values between the strains studied and the W. viridescens type strain confirmed that these strains belong to the latter species. The somewhat divergent results of the pheno- and HindIII ribotyping indicate that W. viridescens is far more heterogeneous species than previously reported.     

Application of multivariate curve resolution to chemical process control of an esterification reaction monitored by near-infrared spectroscopy

Multivariate curve resolution-alternating least squares (MCR-ALS) methodology was applied to near-infrared spectroscopy (NIR) data for the esterification reaction between glycerol and a mixture of caprylic and capric acids. Batch reaction processes were conducted either at the laboratory scale or at an industrial plant, while NIR data were obtained from samples withdrawn during the reaction processes. The process has been monitored via two typical parameters for this type of reaction, namely, the acid value (AV) and the hydroxyl value (OHV). Spectral and concentration profiles were estimated by applying soft-modeling MCR-ALS to a column-wise augmented data matrix with pure spectra of the components, and concentration values for the acid were used as a soft-equality constraint. The estimated concentration profiles have been compared with the AV and OHV values, and the estimated spectral profiles were used to predict the concentration profiles for new batches. Good results have been obtained in terms of RMSE for the prediction of AV and OHV.     

Approaches for the simultaneous extraction of tetrabromobisphenol A, tetrachlorobisphenol A, and related phenolic compounds from sewage sludge and sediment samples based on matrix solid-phase dispersion

A procedure based on matrix solid-phase dispersion (MSPD) for sample preparation in the analysis of some bromophenols and halogenated bisphenols in sediments and sludges has been developed. For the first time ever, MSPD was applied for the extraction of organic contaminants from sediment and sewage sludge samples. The influence of experimental conditions on the yield of the extraction process and on the efficiency of the built-in cleanup step was thoroughly evaluated. Analysis of the extracts was performed by nonaqueous capillary electrophoresis coupled with photodiode array ultraviolet detection, using large-volume sample stacking injection based on the electroosmotic flow pump as an on-column preconcentration technique. The method was applied to the analysis of real sludges from urban sewage treatment plants, as well as river and marine sediment samples.