Tench, Tinca tinca (L.), fish farms as a tool for environmental education

Since 1968, year of the May Revolution in France, UNESCO realised that a rapid separation was developing between the human race and nature, especially in big cities. This resulted in the development of numerous Environmental Education Programmes for children. Tench fish-farms are a particularly good tool for educating children in the structure and function of freshwater ecosystems. The ‘Vegas del Guadiana’ fish farm (Badajoz, Spain) Environmental Education Programme, is included in the Transborder Environmental Education Programme and in INTERREG II, an European Community Initiative whose objective is to promote cross-border, international and interregional co-operation to encourage balanced development in Europe. Preliminary results have been evaluated and presented in the present work. The analysis of the efficiency of the programme was measured in children from ages 6 to 12. The results showed no significant differences among sex (t-Student=0.07, p=0.9470) nor social surroundings (t-Student=0.87, p=0.3910) but there were significant differences when comparing different ages (ANOVA, p=0.0437). In all cases, a significant increase in the knowledge and concern about the freshwater environment was found in children (Paired t-Student=−10.55, p=0.0001).     

Selective behaviour of a tench, Tinca tinca (L.), stock in different light–substrate combined conditions

Two physical factors light or substrate (fibre glass, artificial vegetation, gravel and mud) were determined in a 24 m long artificial channel to have importance on the distribution of 33 tench 2+, mean size 11.8±0.9 cm S.L. For this purpose in five trials tench could select between the half of the channel occupied by their preferred light intensity (inferior to 10 lux) combined with the less preferred substrate (fibre glass) or the half with the combination of one of the substrates considered and higher light conditions (40 lux). Fish preferred, with a 100% frequency, the optimal light-less preferred substrate when compared with the combinations fibre glass, gravel and mud. When artificial vegetation was the substrate considered, tench selected the combination preferred substrate – non-optimal light intensity with a 98.26±2.68% frequency. This result changed when increasing light intensity up to 150 lux, avoiding the shading effect. We demonstrated that light has a bigger influence than substrate in juvenile tench habitat selection under controlled conditions.     

Promoter Trapping in Microalgae Using the Antibiotic Paromomycin as Selective Agent

The lack of highly active endogenous promoters to drive the expression of transgenes is one of the main drawbacks to achieving efficient transformation of many microalgal species. Using the model chlorophyte Chlamydomonas reinhardtii and the paromomycin resistance APHVIII gene from Streptomyces rimosus as a marker, we have demonstrated that random insertion of the promoterless marker gene and subsequent isolation of the most robust transformants allows for the identification of novel strong promoter sequences in microalgae. Digestion of the genomic DNA with an enzyme that has a unique restriction site inside the marker gene and a high number of target sites in the genome of the microalga, followed by inverse PCR, allows for easy determination of the genomic region, which precedes the APHVIII marker gene. In most of the transformants analyzed, the marker gene is inserted in intragenic regions and its expression relies on its adequate insertion in frame with native genes. As an example, one of the new promoters identified was used to direct the expression of the APHVIII marker gene in C. reinhardtii, showing high transformation efficiencies.     

Characterization of cod liver oil by spectroscopic techniques. New approaches for the determination of compositional parameters, acyl groups, and cholesterol from 1h nuclear magnetic resonance and Fourier transform infrared spectral data

Six samples of cod liver oil were studied using Fourier transform infrared (FTIR) spectroscopy and (1)H nuclear magnetic resonance ((1)H NMR). These techniques provide information simply and rapidly about the global features of the cod liver oil main components, showing their potential as routine techniques for evaluating certain parameters of the quality of the cod liver oil. FTIR spectroscopy provides information about the molar percentage of polyunsaturated acyl groups in the sample and also about the ratio between unsaturated and saturated structures. (1)H NMR provides information about the proportions or concentrations of certain acyl groups and also of some minor compounds such as cholesterol. Both techniques are simple and fast. New approaches are presented to evaluate the molar proportions or concentrations of some acyl groups such as the molar percentages of omega-3, docosahexaenoic, and eicosapentaenoic acyl groups; furthermore, some novel approaches for evaluating the molar percentages of unsaturated and saturated acyl groups are also given. Results obtained from both spectroscopic techniques are in total agreement.     

Measurement of free zinc concentration in wine with AGNES

AGNES (absence of gradients and Nernstian equilibrium stripping), a voltammetric technique recently introduced to measure free metal concentration in solution and checked with different natural and synthetic aqueous media, has been applied here to determine free Zn concentration in wine. The content of ethanol in a solution increases its viscosity, and, so, the diffusion coefficient decreases. Another added effect in ethanolic solutions is the increase of the activity of the metal ions, due to the decrease of the permittivity in the alcoholic medium with respect to the aqueous one. With this taken into account, a specific methodology has been developed to apply AGNES in ethanolic media. A relevant point in this methodology has been the introduction of a new kind of blank, the EDTA blank, able to be applied in the same natural sample and with the same potential program. The free Zn concentrations of the two wines analyzed, a red and a white Raimat wine, were 4.5(2) x 10 (-7) and 7.2(4) x 10 (-7) M, respectively. These represent around 5% of the total Zn content. In the wine samples analyzed, it was checked that intermetallic formation of Zn-Cu does not affect the measurement of free Zn in a significant way.     

Molecular and phenotypic characterization of the <Emphasis Type="Italic">S</Emphasis>-locus and determination of flowering time in new ‘Marcona’ and ‘Desmayo Largueta’-type almond (<Emphasis Type="Italic">Prunus dulcis</Emphasis>) selections

‘Marcona’ and ‘Desmayo Largueta’ are the most widely cultivated almonds in Spain, representing around 27% of the total production and 34% of the entire almond growing surface. The excellent quality of their kernels makes them highly appreciated and demanded worldwide. However, due to their self-incompatibility, they should be grown along with cross-compatible cultivars, whose lower kernel quality often reduces the economic benefits of the plantation. In addition, although they are cross-compatible, are not good candidates to share the orchard since ‘Desmayo Largueta’ usually flowers earlier than ‘Marcona’. Therefore, to optimize orchard yield, genotypes with overlapping flowering times, cross-compatible with these cultivars and of similar fruit and ripening characteristics are desirable. In order to find suitable pollinators of these cultivars, five ‘Marcona’ and four ‘Desmayo Largueta’-type selections from “Instituto Técnico Agronómico Provincial (ITAP) de Albacete” (Spain) were characterized for flowering time and for self and cross-incompatibility. The results obtained showed that the nine ITAP selections were self-incompatible, and that three and one were promising candidates as pollinators of ‘Marcona’ and ‘Desmayo Largueta’, respectively. The S-haplotypes of two ITAP selections were characterized by cloning and sequencing their pistil S (S-RNase) and pollen S (SFB) genes. The results also showed that S _f RNase does not have a mutated histidine in C2 region, and detected differences with other previously published sequences for S ₂₃ RNase and SFB ₂₃ allele. Moreover, the sequence for almond SFB ₂₇ allele is reported here for the first time.     

Differentiation of Cotton-defoliating and Nondefoliating Pathotypes of Verticillium dahliae by RAPD and Specific PCR Analyses

Severe Verticillium wilt of cotton in southern Spain is associated with the spread of a highly virulent, defoliating (D) pathotype of Verticillium dahliae. Eleven of the D and 15 of a mildly virulent, nondefoliating (ND) pathotype were analyzed by random amplified polymorphic DNA (RAPD) using the polymerase chain reaction (PCR). Six of 21 primers tested generated pathotype-associated RAPD bands. Another 21 V. dahliae isolates were compared in blind trials both by RAPD-PCR using the six selected primers and pathogenicity tests on cotton cultivars. There was a 100% correlation between pathotype characterization by each method. Unweighted paired group method with arithmetic averages cluster analysis was used to divide the 47 V. dahliae isolates into two clusters that correlated with the D or ND pathotypes. There was more diversity among ND isolates than among D isolates, these latter isolates being almost identical. ND- and D-associated RAPD bands of 2.0 and 1.0kb, respectively, were cloned, sequenced, and used to design specific primers for the D and ND pathotypes. These pathotype-associated RAPD bands were present only in the genome of the pathotype from which they were amplified, as shown by Southern hybridization. The specific primers amplified only one DNA band of the expected size, and in the correct pathotype, when used for PCR with high annealing temperature. These specific primers successfully characterized V. dahliae cotton isolates from China and California as to D or ND pathotypes, thus demonstrating the validity and wide applicability of the results.     

Assessment of the spectrophotometric method for determination of angiotensin-converting-enzyme activity: influence of the inhibition type

A set of in vitro assay conditions were selected for the determination of ACE-inhibitory activity, and the need was demonstrated to standardize this assay so that the results obtained by different authors may be comparable. The conditions selected were as follows: 10 mM HHL concentration in 0.2 M potassium phosphate buffer and 0.3 M NaCl and 26 mU of ACE/mL as reaction medium; incubation time, 80 min at 37 degrees C. The method was applied to the study of ACE-inhibitory activity of dairy product and wine samples. Of the samples assayed, it was infant formulae whey that produces the greatest ACE inhibition. Red wine also presents a high inhibition percentage. This latter sample has an important matrix effect that must be corrected in the calculation. ACE-inhibition type was also studied, using a yogurt whey and a Captropil solution as substrates. The whey produced noncompetitive inhibition and the Captropil competitive inhibition.     

Comparative Study of Genetic Diversity and Pathogenicity Among Populations of Verticillium Dahliae from Cotton in Spain and Israel

Genetic diversity and phenotypic diversity in Verticillium dahliae populations on cotton were studied among 62 isolates from Spain and 49 isolates from Israel, using vegetative compatibility grouping (VCG), virulence and molecular assays. In Spain, defoliating V. dahliae isolates (D pathotype) belong to VCG1, and non-defoliating isolates (ND) belong to VCG2A (often associated with tomato) and VCG4B (often associated with potato). The D pathotype was not identified in Israel. The ND pathotype in Israel is comprised of VCG2B and VCG4B. Isolates in VCG2B and VCG4B ranged in virulence from weakly virulent to highly virulent. The highly virulent isolates induced either partial defoliation or no defoliation. Virulence characteristics varied with inoculation method and cotton cultivar. Highly virulent isolates from Israel were as virulent as D isolates from Spain under conditions conducive to severe disease. The D pathotype is pathologically and genetically homogeneous, whereas the ND pathotype is heterogeneous with respect to virulence, VCG, and molecular markers based on single-primer RAPD and on PCR primer pairs.     

Evidence of the formation of light polycyclic aromatic hydrocarbons during the oxidation of edible oils in closed containers at room temperature

Solid phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) of the headspace composition of two sunflower oil samples was carried out; both samples were taken from the same original oil, stored for a prolonged time (112 months) in closed containers at room temperature under different air/oil volume ratios. Great differences in the headspace compositions of both samples were found due to the different oxidation levels reached. One of the most significant findings is that both contain monocyclic and light polycyclic aromatic hydrocarbons, the proportions of which are in line with the oxidation level of the sample. The determination of polycyclic aromatic compounds in the oil liquid matrix of both oil samples, carried out by means of a classical scheme of isolation, cleanup, separation, and quantification, showed that the concentrations of these compounds in the oil liquid phase also follow the oxidation degree reached by each sample, proving that this oxidation process at room temperature leads to the formation of these compounds.