Molecular basis of the interaction between proteins of plant origin and proanthocyanidins in a model wine system

Plant proteins are being used as a replacement for animal proteins in wine fining. The surface hydrophobicity of plant proteins in four commercial preparations differing for their origin and processing was assessed by using a fluorescent hydrophobic probe in wine-like media. Displacement of the probe by addition of wine phenolics was measured as a way to compare and predict to some extent the efficiency of these proteins in wine fining. It was found that the binding of polyphenols was much more specific than that of the hydrophobic probe. Further analysis of the polyphenol pattern in protein-treated wine-like solutions pointed out two relevant facts: (1) proteins may interfere with the chemistry of the interactions between polyphenols and other wine components; (2) individual protein preparation having different surface hydrophobicities also have different specificities in binding different polymeric forms of the polyphenols and in their substitution products. These findings are related to the possible carry-over of transition metals and may be worth exploring for custom tailoring the fining process. Whether the practical application of the latter finding will call for production and/or screening of plant-derived proteins with features appropriate to this task remains to be investigated. However, the approaches presented in this study may be used for large-scale screening of protein suitability for fining application under laboratory conditions, providing guidelines for their use in actual winemaking applications.     

Copromicroscopic and molecular assays for the detection of cancer-causing parasitic nematode Spirocerca lupi

Spirocerca lupi (Nematoda, Spirurida) is a life-threatening parasitic nematode of dogs that is presently emerging in several countries. Nonetheless, canine spirocercosis is neglected and underestimated, mainly due to diagnostic limitations inherent to clinico-pathologic, diagnostic imaging and laboratory methodologies. Given the significant benefit of improved diagnosis, the present work evaluated the reliability of a recently described copromicroscopic approach, the FLOTAC technique, as well as a PCR-based assay with that of traditional coproscopic techniques to diagnose S. lupi infection. Ninety-four faecal field samples were collected from two endemic areas (i.e. 29 and 65 from Kenya and Israel, respectively) and processed using different coproscopic examination techniques. In particular, set I (Kenyan samples) comprised the modified flotation with Sheather's sugar solution and merthiolate-iodine-formalin technique, while set II (Israeli samples) comprised a flotation technique with zinc sulphate solution, a modified sugar flotation procedure and the FLOTAC method. All samples were also subjected to a semi-nested PCR protocol specific for a region internal to the mitochondrial cytochrome c oxidase subunit 1 gene of S. lupi. The coproscopic examinations showed low sensitivity and high variability, demonstrating the unreliability of the conventional methods for detecting S. lupi eggs. Nonetheless, the FLOTAC technique scored the highest number of positives and significantly higher number of S. lupi eggs per microscopic field compared to the other coproscopic methods. Additionally, of the coproscopically negative samples, 9 (45%) Kenyan and 21 (38.2%) Israeli samples scored molecularly positive using the PCR-based approach. The potential implications and perspectives for canine spirocercosis of these coproscopic and molecular diagnostic methodologies evaluated herein are discussed.     

Phytochemical Characterization and Effects on Cell Proliferation of Lentisk (Pistacia lentiscus) Berry Oil: a Revalued Source of Phenolics

Plant Foods for Human Nutrition - The ethno-pharmaceutical use of the edible fixed oil produced from lentisk (Pistacia lentiscus) berries covers a long tradition in several Mediterranean regions....     

High-Performance Liquid Chromatography/Electrospray Ionization Tandem Mass Spectrometry (HPLC-ESI-MSn) Analysis and Bioactivity Useful for Prevention of “Diabesity” of Allium commutatum Guss

Plant Foods for Human Nutrition - This study aimed at evaluating and comparing the chemical profile obtained by HPLC-ESI-MSn analysis, the inhibitory activity of enzymes linked to obesity...     

Determination and Comparison of the Lipid Profile and Sodium Content of Gluten-Free and Gluten-Containing Breads from the Spanish Market

Plant Foods for Human Nutrition - The objective is to verify if gluten-free (GF) and gluten-containing (G) breads differ in their sodium content and lipid profile. Samples of GF...     

Choice of selection strategy in breeding barley for stress environments

To determine the optimum selection environment for barley (Hordeum vulgare L.) targeted at low-input, stress environment, barley lines were selected for high yield under stress (YS), high yield under non-stress (YNS), or average yield in stress and non-stress conditions (YA) during three breeding cycles (cohorts) of three years each. The lines were then tested in a total of 21 year-location combinations with average grain yields ranging from 0.35 to 4.86 t ha^-1. Yield under stress of the YS lines was between 27% and 54% higher than that of the YNS lines, with the top YS lines yielding under stress between 16% and 30% more than the top YNS lines. Realized heritability was between 0.35 and 0.67 when selection was conducted under stress and was significant in all three cohorts. By contrast, selection under non-stress gave a significant response in only one cohort, and its efficiency in improving yield under stress was significantly lower than selection under stress. The best YNS line ranked only 19th for yield under stress. The highest-yielding lines under stress were not only selected under stress, but were also landraces collected in very dry areas (< 250 mm total annual rainfall). This confirms earlier findings and supports the idea that the most effective way to improve productivity of crops grown in less-favored areas is to use locally adapted germplasm and select in the target environment(s). This revised version was published online in July 2006 with corrections to the Cover Date.     

Suppressive activity of some glucosinolate enzyme degradation products on Pythium irregulare and Rhizoctonia solani in sterile soil

Glucosinolate degradation products (GLDPs), mainly isothiocyanates, obtained by myrosinase‐catalysed hydrolysis of glucosinolates (GLs), are an important group of natural bioactive substances. The fungitoxic activity of four GLDPs, chosen on the basis of their side‐chain structures, was assayed against Pythium irregulare and Rhizoctonia solani. The effectiveness of the degradation products (DPs) of sinigrin (alkenyl GL), epi‐progoitrin (hydroxy‐alkenyl GL), glucoiberin and glucoerucin (thiofunctionalised GLs) in inhibiting P irregulare oospore germination and R solani soil colonisation were tested in a closed system, using an artificially infected soil. The fungitoxic activity of these GLDPs varied according to their side‐chain structure. As in previous in vitro studies, the thiofunctionalised GLDPs were found the most effective, producing complete inhibition of P irregulare oospore germination (0.01 µmole g⁻¹ soil) and R solani soil colonisation (0.5 µmole g⁻¹ soil), but even sinigrin DP showed a fungitoxic activity higher than that of epi‐progoitrin DP. © 2000 Society of Chemical Industry     

Effect of stocking density and protein/fat ratio of the diet on the growth of Dover sole (Solea solea)

Two hundred and fifty soles (30 g initial weight) were randomly stocked in 12 tanks (recirculation system) at two different stocking densities (2.3 and 1.3 kg m^?2) and fed on two different diets (50% and 54% of crude protein and 21% and 18% of total lipid, respectively, for diets A and B) with triplicate tanks for treatment. The trial lasted for 300 days. Fish stocked at low density showed a significantly higher weight gain than the fish reared at 2.3 kg m^?2 density (94.1±7.4 vs. 78.9±8.2 g, P<0.01) with a specific growth rate (SGR) of 0.46±0.11 and 0.43±0.16 (P<0.01) respectively. Feed conversion ratio (FCR) was more favourable for lower density groups (2.50 vs. 2.64, P<0.01). Diet B led to a higher final weight (124.1 vs. 110.2 g, P<0.01) and a better feed utilization (FCR: 2.49 vs. 2.65, P<0.01). Except for the lipid content, which was higher in the low‐density group (2.6% vs. 2.3%, P<0.05), proximate composition of sole's muscle was not influenced by treatments. Dover sole reared at low stocking density showed higher monounsaturated fatty acid (35.27% vs. 34.40%, P<0.01) and lower saturated fatty acid (24.36 vs. 26.13%, P<0.01) contents, and lower atherogenic (0.67 vs. 0.75, P<0.01) and thrombogenic (0.28 vs. 0.32, P<0.01) indexes.     

Differential Responses of Barley Landraces and Improved Barley Cultivars to Nitrogen-Phosphorus Fertilizer

Barley is traditionally grown in the Mediterranean region as a dryland crop, invariably under drought-stressed conditions and often without inputs such as fertilizer. Following research that demonstrated the benefits of fertilization, even under less-than-favourable rainfall condition, fertilizer use on cereals has increased dramatically in the past few decades in countries of West Asia-North Africa. With developments in breeding new barley cultivars for higher yield, combined with disease resistance and environmental adaptability, it is crucial to assess the extent to which such cultivars respond to fertilizer inputs as this may affect aspects of a breeding strategy, particularly the choice of germplasm for adaptation in any particular environment. Thus, we assessed the yield potential of 30 barley cultivars with a range of germplasm types, including new cultivars and landraces, in a greenhouse in two soil types with and without adequate nitrogen and phosphorus fertilizer, i.e., low and high fertility. By comparison with the unfertilized low fertility soils, the fertilizer treatment increased yield parameters by about 10-fold. However, the rankings of some cultivars changed markedly with fertilization; some increased, others showed poor responses and decreased relatively, and two performed well with and without fertilizer. Based on the differential responses at the initial screening stage in the greenhouse, it is possible to identify lines or cultivars that are highly responsive to fertilizers and to incorporate such germplasm for further development to produce high-yielding cultivars for commercial adoption by farmers.