Protective Effect of <Emphasis Type="Italic">Juglans regia</Emphasis> L. Walnut Extract Against Oxidative DNA Damage

Walnuts (Juglans regia L.) are relevant components of the Mediterranean diet providing important macronutrients, micronutrients and other bioactive constituents including unsaturated fatty acids, proteins, fiber, vitamins, minerals, phytosterols and polyphenols. Although the walnut beneficial effects in human health are widely recognized by a lot of epidemiologic studies very little is known regarding its effect on damaged DNA. The aim of the present study was to investigate the effect of Juglans regia L. ethanolic extract from kernel on the induction of DNA strand breaks by thiol/Fe³⁺/O₂ mixed function oxidase, tert-butyl hydroperoxide or UVC radiations in acellular and cellular models. Plasmid DNA cleavage and fast Halo assay were used to monitor oxidative damage to DNA. Both approaches showed protection of oxidatively injured DNA. These results agree with a lot of scientific proofs which recommend walnut as dietary adjunct in health promotion and prevention as well as in treatment of lifestyle-related oxidative diseases.     

Productive and biochemical responses of durum wheat to UV filtration

A UV exclusion experiment was conducted on durum wheat (Triticum durum Desf. var. Claudio) grown in pots. Plants were grown under three different radiative treatments in greenhouses covered with plastic filters: Teflon, transparent to the entire region of natural UV‐visible sunlight (TEF); polyester, transparent above 312 nm (MYL, excluding UVB) and Lee, transparent above 400 nm (LEE, excluding both UVA and UVB). Analyses have been carried out to determine the concentration of photosynthetic pigments in leaves, UV‐absorbing compounds, nitrogen and carbon in leaves, culms and spikes and proteins and gluten in grains. In particular, plants grown under UV exclusion showed a reduction in protein and dry gluten content (consequently without variation in the ratio dry gluten/protein), but at the same time, a significant increase of gluten index, which is a parameter to define the quality of gluten, was observed. The results highlighted the influence played by UV radiation on some biochemical parameters, mainly UV‐absorbing compounds, leaf nitrogen and grain protein characteristics of durum wheat cultivated under Mediterranean conditions. In particular, natural level of UV in the Mediterranean improves the characteristics of durum wheat flour important for pasta production (high dry gluten level), while the UV exclusion could improve characteristics of flour important for bread production (high gluten index).     

Effects of accumulate dead and alive insects in trap on the capture ofTribolium castaneum (herbst)

In the trapping ofTribolium castaneum (Herbst), the activity of traps baited or not baited with aggregation pheromone 4,8-dimethyldecanal is influenced by the presence in the traps of accumulate specimens trapped. This fact has been observed both in trap containing alive or dead specimens. Interactions in the different substances produced by adults of Red Flour Beetle during their communication relationship are involved in this behaviour.The results obtained in the trials suggests that the presence of alive insects in traps is attractive for other free specimens, but under conditions of overcrowding quinone produced by them regulate population density by counteracting the effect of the aggregation pheromone, causing the insects to disperse or suppressing aggregation behaviour.The presence of dead insects in the traps, baited or not baited with pheromone, can be repellent for other free specimens ofT. castaneum, probably related to the presence of a residual alarm pheromone produced by the specimens before of death.With 10 figures and 3 tables     

Broodstock spawning and larviculture of whiting (Merlangius merlangus L.) reared in captivity

In recent years, an increasing interest in the farming of marine ‘white’ fish, such as cod, has been observed in the aquaculture industry. One species being considered for aquaculture development is whiting (Merlangius merlangus L.). With little data being available on the domestication of this species, our study aimed to characterize spawning behaviour and rhythmicity in captive broodstock and provide original data on egg incubation, embryonic development and larval rearing. The results observed through video recording showed that spawning mainly occurred at night with active courtship behaviour. Daily egg batches were collected from two separate spawning seasons, with an average fertilization success declining from 77% to 53%. Time to hatch was inversely related to the incubation temperature and occurred after 78 degree‐days (9 days at 8 °C), with emerging larvae ranging in size from 3.3 to 3.46 mm total length and hatch success ranging from 48.3% to 99.9%. In comparison with a clear water environment, a green water regime during the first days of larval rearing significantly improved larval growth and survival. These results are the first to describe spawning activity, early development and larval performances in whiting and are promising for the potential future development of whiting aquaculture.     

Inverse Modeling to Quantify Irrigation System Characteristics and Operational Management

Remotely sensed (RS) data is a major source to obtain spatialdata required for hydrological models. The challenge for thefuture is to obtain besides the more direct observable data(landcover, leaf area index, digital elevation model andevapotranspiration), non-visible data such as soilcharacteristics, groundwater depth and irrigation practices.In this study we have explore the option of using inversemodeling to obtain these non-RS-visible data. For a commandarea in Haryana, India, we applied for the 2000–2001 rabiseason a RS-GIS-combined inverse modeling approach to derivenon-RS-visible data required in the regional application ofhydrological models. A Genetic Algorithm loaded stochasticphysically based soil-water-atmosphere-plant model (SWAP) wasdeveloped for the inverse problem and used in the study. Theresults showed good agreement with the inventoried data suchas soil hydraulic properties, sowing dates, groundwaterdepths, irrigation practices and water quality. The deriveddata could be used to predict the state of the system at anytime in the cropping season, which can be used to evaluateoperational management strategies.     

Determination of the activity of acidic phytate-degrading enzymes in cereal seeds

Five different methods were compared to elucidate the total activity of the acidic phytate-degrading enzymes present in the seeds of rye, wheat, and barley. Phytate-degrading activity was studied at pH 5.0 by quantifying the liberated phosphate. Rye showed the highest acid phytate-degrading activity among the cereals studied. Using an aqueous extract, only 30-50% of the activity was found (rye, 3443 mU g(-1) of grain; wheat, 1026 mU g(-1) of grain; barley, 1032 mU g(-1) of grain) compared to that found by the direct incubation of the dry-milled cereal grains in a buffered phytate-containing solution (rye, 6752 mU g(-1) of grain; wheat, 2931 mU g(-1) of grain; barley, 2093 mU g(-1) of grain). Extending the extraction time resulted in an increase in extractable phytate-degrading activity by, at maximum, 10-15%. Extraction of phytate-degrading activity is strongly enhanced in the presence of Triton X-100 and the protease inhibitor phenylmethylsulfonyl fluoride (rye, 6536 mU g(-1) of grain; wheat, 2873 mU g(-1) of grain; barley, 2023 mU g(-1) of grain), suggesting at least a partial association with membrane structures and a degradation by proteolytic activity during extraction. In addition, it was shown that determining phytate-degrading activity by quantification of the liberated inorganic phosphate is more robust and precise than determining phytate-degrading activity by quantification of the residual phytate.     

Interactions between mitochondrial lipid oxidation and oxymyoglobin oxidation and the effects of vitamin E

Off-flavor and discoloration of meat products result from lipid oxidation and myoglobin (Mb) oxidation, respectively, and these two processes appear to be interrelated. The objective of this study was to investigate their potential interaction in mitochondria and the effects of mitochondrial alpha-tocopherol concentrations on lipid oxidation and metmyoglobin (MetMb) formation in vitro. The addition of ascorbic acid and ferric chloride (AA-Fe(3+)) increased ovine and bovine mitochondrial lipid oxidation when compared with their controls (p < 0.05); MetMb formation also increased with increased lipid oxidation relative to controls (p < 0.05). Reactions containing Mb and mitochondria with greater alpha-tocopherol concentrations demonstrated less lipid oxidation and MetMb formation than mitochondria with lower alpha-tocopherol concentrations. Greater mitochondrial alpha-tocopherol concentration was also correlated with increased mitochondrial oxygen consumption in vitro and with a more pronounced effect at pH 7.2 than at pH 5.6. Relative to controls, succinate addition to bovine mitochondria resulted in increased concentrations of ubiquinol 10 and alpha-tocopherol and decreased lipid and Mb oxidation (p < 0.05). Mitochondrial lipid oxidation was closely related to MetMb formation; both processes were inhibited by alpha-tocopherol in a concentration-dependent manner.     

Color stability, reducing activity, and cytochrome c oxidase activity of five bovine muscles

The objective was to characterize the beef psoas major (PM), longissimus lumborum (LL), superficial semimembranosus (SSM), deep semimembranosus (DSM), and semitendinosus (ST) muscles for differences in instrumental and visual color, metmyoglobin-reducing activity (MRA), total reducing activity (TRA), and cytochrome c oxidase activity. The LL and ST had the most color stability and MRA (p < 0.05), the DSM and PM had the least (p < 0.05), and values for the SSM were intermediate. Visual color (r = -0.66) and a and chroma (r = 0.68) were more correlated with MRA than with TRA (r < 0.14 for all measures). This research supports previous reports that color stability among muscles is variable and that MRA is more useful than TRA for explaining the role of reducing activity in muscle-color stability.     

Mitochondrial reduction of metmyoglobin: dependence on the electron transport chain

Reduction of ferric myoglobin (metmyoglobin, MetMb) to its ferrous form is important for maintaining fresh meat color because only reduced myoglobin can bind oxygen to form the consumer-preferred cherry red color in fresh meat. The objective of this study was to characterize an apparent mitochondria electron transport chain (ETC)-linked pathway for MetMb reduction in vitro. MetMb was reduced in the presence of mitochondria and succinate (p < 0.05); mitochondria or succinate alone did not facilitate MetMb reduction relative to controls (p > 0.05). Flushing samples with oxygen greatly decreased MetMb reduction, while flushing with argon increased MetMb reduction when compared with controls (p < 0.05). ETC inhibitors were used to localize the site where electrons became available for MetMb reduction. MetMb reduction was increased by rotenone addition and decreased by malonic acid (p < 0.05); the reduction was completely abolished by additions of antimycin A or myxothiazol when compared with controls (p < 0.05). These results suggest that electrons become available for MetMb reduction at a site(s) between complex III and IV. Mitochondrial ETC-linked MetMb reduction increased with increased mitochondrial density and succinate concentration (p < 0.05); the greatest MetMb reduction was observed at pH 7.2 and 37 degrees C, and ETC-linked MetMb reducing activity decreased with time postmortem (p < 0.05). These results indicate that ETC-linked MetMb reduction exists but would be minimally active in postmortem muscles.     

Novel application of square-wave adsorptive-stripping voltammetry for the determination of xanthohumol in spent hops

This paper reports the development of a novel electrochemical assay for xanthohumol (XN) by square-wave adsorptive-stripping voltammetry (SWAdSV) with a hanging mercury drop electrode. The method showed good repeatability (CV < 2%) and linearity (between 10 and 250 μg L(-1)), as well as suitable limits of detection (2.6 μg L(-1)) and quantification (8.8 μg L(-1)). The method was applied for the quantification of this compound in spent hops, and the results obtained were compared with the HPLC-UV method. XN contents determined by the SWAdSV method were 16 ± 1 and 100 ± 4 μg L(-1) for aqueous and methanolic extracts, respectively. The developed new methodology considerably reduces the analysis time, approximately from 25 min (HPLC-UV method) to 7 min, enabling a high sample throughput. In addition, the detection and quantification limits were approximately 5-fold lower than those obtained with the chromatographic method.