Risk levels of toxic cyanobacteria in portuguese recreational freshwaters

Portuguese surface freshwaters are widely used as a source of drinking water as well as bathing water. Cyanobacterial blooming in these water resources are common and are often associated with cyanotoxin production. The Portuguese legislation for drinking water (Decreto-Lei nº306/2007) establishes the regulatory level of 1 μg/L for total microcystins in treated water. This parameter is determined when eutrophication of water is suspected and when the number of potentially toxic cyanobacteria exceeds 2000 cells/mL. Conversely, the Portuguese legislation concerning the quality of bathing water (Decreto-Lei nº 135/2009), that was transposed form the European Directive nº2006/7/CE, do not include any guideline for cyanobacterial cells nor microcystins concentrations. It only recommends that when the bathing water profile indicates a potential for cyanobacterial proliferation, appropriate monitoring shall be carried out to enable timely identification of health risks. When cyanobacterial proliferation is detected visually, it is the responsibility of the local health delegate to evaluate the associated risk. If any risk has been identified or presumed, health and environmental authorities should implement the adequate management measures to prevent exposure, including information to the public. According to national specificities, some European countries complemented the European Directive nº2006/7/CE and implemented their own guidance or regulations, based on cyanobacterial cell numbers, biovolumes, pigments and/or cyanotoxin concentrations (Ibelings et al., 2015; Chorus, 2012). Prior to establishing regulatory or guideline values, it will be fundamental to characterize Portuguese inland bathing waters concerning the frequency, density, specie composition and toxicity of cyanobacterial blooms. These data are available but not systematized at a national scale. In this work we present the results of the monitoring of cyanobacteria and microcystins in 8 freshwater reservoirs located in the centre of Portugal largely used for bathing and recreational activities. These results will contribute to identify the cyanobacterial blooms profile and to assess the risk level of toxic cyanobacteria in Portuguese recreational freshwaters.N/

Wine astringent compounds monitored by an electrochemical biosensor

An innovative approach for monitoring astringent polyphenols in beverages (wines) is described, consisting of an electrochemical biosensor constructed by adsorbing salivary α-amylase or proline-rich protein (PRP) onto amined gold screen-printed electrodes. Interaction with polyphenols was tested using pentagalloyl glucose (PGG) as a standard, an important representative element for astringency. The analytical properties of the resulting biosensors were evaluated by electrochemical impedance spectroscopy at different pHs. The PRP-biosensor was able to bind to PGG with higher sensitivity, displaying lower limit of the linear range of 0.6 μM. Wine samples were tested to prove the concept and the concentrations obtained ranged from 0.17 to 4.7 μM, as expressed in PGG units. The effects of side-compounds on PRP and on α-amylase binding to PGG were tested (gallic acid, catechin, ethanol, glucose, fructose and glycerol) and considered negligible. Overall, concentrations > 1.0 μM in PGG units are signaling electrochemical impedance, providing a quantitative monitoring of astringent compounds.FoodNanoSense, Compreensão do amargor e adstringência dos polifenóis presentes em alimentos para o desenvolvimento de um biossensor, supported by Fundação para a Ciência e Tecnologia, with reference PTDC/AGR-TEC/6547/2014.info:eu-repo/semantics/publishedVersio

Safety of frozen vegetables: a case study on carrots

Consumers are confident in frozen foods, which is a consequence of proven safety and quality characteristics of the products. However, safety depends strongly on the quality of the raw materials, the hygienic conditions when handling both at industrial and home processing, and on the temperature conditions during the entire logistic chain. Bacteria survival depends upon a number of factors, such as type of microorganism, freezing process, rate of freezing, storage temperatures and freeze-thaw cycles. The goal of this work was to quantify the impact of the freezing operation per si and frozen storage, at two temperatures (-7º and –20 ºC), on total aerobes, yeast and moulds levels on shredded carrots (Daucus carrota L.). Results showed that, for both temperatures analyzed, the freezing operation itself had a significant effect (p<0,05) in reducing microbial counts, when compared with the initial levels. Storage temperature did not influence significantly mesophilic aerobic flora levels (p<0,05). However, yeasts counts in samples stored at –20ºC presented a gradual decline along the storage period, being significantly lower than samples at -7ºC, after 10 days of storage. Moulds were not detected in all analyzed samples

Impact of grape pectic polysaccharides on anthocyanins thermostability

The impact of grape pectic polysaccharides on malvidin-3-O-β-d-glucoside thermostability was evaluated in model solutions. Pectic polysaccharides richer in homogalacturonan domains, with less neutral sidechains (chelator fraction) showed higher binding with malvidin-3-O-β-d-glucoside, by 1H NMR (Ka=505 M-1). Binding affinity with water soluble extract was estimated to be 10-fold lower, possibly due to the presence of neutral branched regions and more compacted structure, hampering the binding. Hydrophobic domains, such as rhamnogalacturonans-I domains in acid soluble polysaccharides, may participate in the formation of complexes with malvidin-3-O-β-d-glucoside. The thermostability of anthocyanin-polysaccharides complexes was evaluated at different temperatures, assessing anthocyanins degradation by HPLC-DAD. Polysaccharides showed to improve anthocyanin thermostability, with chelator and acid extract having the highest impact at lowest temperatures. Electrostatic interactions, additionally stabilized by hydrophobic effect contribute to the anthocyanin-polysaccharides binding and to the consequent thermostabilization. The protection provided by grape pectic polysaccharides foresees innovative anthocyanin food products with improved thermostability and colour features.publishe

Model of clinical internship: a new approach

Clinical internship is an integral part of the University of Aveiro, School of Health study programs for all majors: Nursing, Physical Therapy, Radiology, Radiotherapy, and Speech-Language Pathology. Clinical internship consists of a learning period where professional skills are integrated and promoted, and expertise is developed. It begins during the first year, and progressively increases in time during the subsequent semesters, until the last year, when it becomes full-time. The clinical internship of each major is a continuous growing process of professional capacities that gradually increases in development expertise, and is cumulative, synergetic and interactive. This new learning approach is common to all the majors, it is characterized by innovation, and it strives to assure the development of professional skills through the integration of knowledge acquired during theoretical lectures. Thus, future professionals should be autonomous, responsible, capable of thought-based critique, fit to implement innovations, and motivated for a life-time of self-learning. Within this context, an ecological model of thought-based clinical practice includes three factors: activities, roles, and interpersonal relationships. It is based on the principles of observation, experience and analysis of the pre-professional practice, thought-based, and systematically orientated by academic faculty and working professionals. The methodology encompasses two areas: multidisciplinary (conceptualisation and organization of the various internships programs, with faculty of the different academic programs as well as working professionals), and management model (forecast of the required material and human resources; creation of a Internship Program Centre; systematic monitoring of the structure, processes and results). Analysis of the first and second clinical internship has shown a great acceptance on behalf of all participants (students, faculty and working professionals). Statistical data will be presented at the conference.publishe