Indirect enzyme-linked immunosorbent assay for the identification of sole (Solea solea), European plaice (Pleuronectes platessa), flounder (Platichthys flesus), and Greenland halibut (Reinhardtius hippoglossoides).

Polyclonal antibodies produced against soluble muscle protein extracts from sole (Solea solea), European plaice (Pleuronectes platessa), flounder (Platichthys flesus), and Greenland halibut (Reinhardtius hippoglossoides) were used in an indirect enzyme-linked immunosorbent assay for the specific identification of fillets from these flatfish species. The assay was performed in two different formats: microtiter plates and immunostick tubes. Immunorecognition of antibodies adsorbed to their specific fish samples was made with goat antirabbit immunoglobulins conjugated to the enzyme horseradish peroxidase. Subsequent enzymatic conversion of the substrate allowed unequivocal identification of all flatfish species studied.     

Responses of Holstein cows to a low dose of somatotropin (bST) prepartum and postpartum

Objectives were to evaluate the effects of a low dose of bovine somatotropin (bST) injected prepartum and postpartum on body condition score (BCS), body weight (BW), and milk yield (MY) in cows as well as somatotropin insulin, insulin-like growth factor-I (IGF-I), glucose, and nonesterified fatty acids (NEFA) in plasma. Holstein cows nearing second or later parities were assigned randomly to control (CON = 98) or bST-treated (TRT = 95) groups. Biweekly injections of bST began 21 +/- 3 d before expected calving and continued through 42 d postpartum (CON vs. TRT; 0 vs. 10.2 mg of bST/ d). From 42 to 100 d postpartum, no cows received bST. During yr 1, somatotropin, IGF-I, insulin, NEFA, and glucose were measured in plasma samples from 82 cows. During yr 2, effects of bST on BCS and BW of 111 cows were evaluated, but no blood samples were collected. Milk yields through 100 d of all 193 cows were analyzed. Prepartum treatment with bST resulted in greater prepartum plasma concentrations of somatotropin, insulin, and numerically greater NEFA but did not affect glucose or IGF-I. Postpartum bST increased mean plasma concentrations of somatotropin and NEFA, but not INS, IGF-I, or glucose. Mean BCS of cows did not differ prepartum, around parturition, or postpartum. Although mean BW did not differ prepartum or around calving, cows receiving bST maintained greater BW postpartum. Cows receiving bST tended to have higher MY (6.6%) in the first 60 d of lactation, but differences did not persist through 100 d, including approximately 40 d when no cows received bST. Number of cows that were culled due to health (CON = 3 vs. TRT = 2) or died (CON = 3 vs. TRT = 1) were not affected by treatment. Low doses of bST in the transition period resulted in higher postpartum BW, quicker recovery of body condition during lactation, and significantly more milk during treatment.     

Common pattern of gene expression in response to hypoxia or cadmium in the gills of the European glass eel (Anguilla anguilla)

European eel (Anguilla anguilla) populations are in decline. Glass eel recruitment has fallen 10-fold since the early 1980s. Estuaries play a fundamental role in the life history of eels because glass eels must pass through them to reach freshwater ecosystems. Unfortunately, because of their geographical position at the upstream basin slopes, estuaries accumulate metals like cadmium and are important sites of hypoxia events. In this context, we studied the effect of the oxygen level on the ventilation of the glass eel. In parallel, glass eels were submitted to different dissolved cadmium concentrations (0, 2, and 10 microg L(-1)) under two oxygen levels (normoxia PO2 = 21 kPa and Hypoxia PO2 = 6 kPa). The expression level of various genes involved in the mitochondrial respiratory chain, in the cellular response to metal and oxidative stresses, was investigated. Our results showed that hypoxia enhances (1) ventilation of the postlarval stage and (2) Cd accumulation in gills only at the lowest metal water concentration tested (2 microg Cd L(-1)). At the gene level, Cd exposure mimics the effect of hypoxia since we observed a decrease in expression of genes involved in the respiratory chain and in the defense against oxidative stress.     

Olfactory bulb uptake and determination of biotransfer factors in the California ground squirrel (Spermophilus beecheyi) exposed to manganese and cadmium in environmental habitats

Manganese (Mn) and cadmium (Cd) profiles in olfactory bulbs of California ground squirrels (Spermophilus beecheyi) trapped at Lawrence Livermore National Laboratory's Site 300 facility in California were determined with proton induced X-ray emission (PIXE). As a reference, Mn profiles in olfactory bulbs from laboratory rats exposed via nose-only inhalation to 0.53 mg/m3 Mn in the form of MnCl2 were also determined with PIXE. Atomic absorption spectrophotometry was used to measure soil Mn and Cd contents from the trapping sites and Mn and Cd contents in ground squirrel liver and leg muscle tissues. The data from laboratory rats revealed that Mn uptake into the olfactory bulb occurs via inhalation exposure. Data from ground squirrels and knowledge of the collection sites indicate that although several routes of exposure may occur, fossorial rodent olfactory uptake affords a significant exposure route to Mn and Cd in soils. Measured biotransfer factors (ratio of leg muscle tissue metal content to soil metal content) for Cd in ground squirrels were 10(3)-fold greater than exposure modeling estimates based on oral Cd uptake data from livestock. The measurements for ground squirrel tissues show that when conducting ecological risk assessments for natural habitats considerable care should be taken in selecting transfer factors. Specifically, transfer factors derived from data pertaining to comparable exposure pathways and ecological setting should be used wherever possible.     

Implicit evaluation of the emotional response to premium organic herbal infusions through a temporal dominance approach: Development of the temporal dominance of facial emotions (TDFE)

One of the greatest challenges when designing research on emotions is the conception of an efficient tool for their measurement. The FaceReader™ emerged as an implicit tool capable of analysing facial expression patterns whether in recorded or real-time videos. This software produces large datasets on temporal variation of the intensity of basic emotions.The main goals of this research were: (i) to develop a new data analysis procedure, based on temporal dominance approaches to evaluate temporal data from Face Reader, called the Temporal Dominance of Facial Emotions (TDFE), (ii) to relate the results from TDFE with the EsSense Profile® evaluation, (iii) to evaluate different market samples and to establish its emotional profile.An untrained panel of 50 naïve panellists tasted five samples. For each infusion, the overall liking was evaluated using a 9-point scale (1-dislike extremely to 9-like extremely) followed by the evaluation of the emotional profile, using an adapted version of the EsSense Profile®. The entire test was video- recorded using web cameras placed in front of the panellists and adjusted, to obtain a correct measurement of their facial expressions.Significant differences (p ≤ 0.05) between samples were found for overall liking. The correlation between TDFE and EsSense Profile® was 0.704, above the reference value of 0.680. However, from both methods one can identify a clear emotional profile of the samples under evaluation.Both methodologies appear to be promising regarding the emotional profile characterization. However, the lower direct correlation can be explained by the difference in positive and negative emotions. FaceReader™ identifies more negative than positive emotions, while the EsSense Profile® identified the opposite. Therefore, both approaches should be regarded as complementary.     

Cellular and transcriptional responses of yeast to the cleavage of cytosolic tRNAs induced by colicin D

Colicin D is a plasmid‐encoded antibacterial protein that specifically cleaves the anticodon loops of four Escherichia coli tRNA^Arg species. Here, we report that the catalytic domain of colicin D, which is expressed in Saccharomyces cerevisiae, impairs cell growth by cleaving specific tRNAs. DNA microarray analysis revealed that mating‐related genes were upregulated, while genes involved in a range of metabolic processes were downregulated, thereby impairing cell growth. The pheromone‐signalling pathway was activated only in α cells by tRNA cleavage, which was not observed in ‘a’ cells or diploid cells. On the basis of these results and on the recent identification of two killer toxins that cleave specific tRNAs, the relationship between tRNA depletion and the resultant cellular response is discussed. Copyright © 2009 John Wiley & Sons, Ltd.     

Effects of low dose gamma irradiation on microbial inactivation and physicochemical properties of fried shrimp (Penaeus vannamei)

Changes in microbiological, physicochemical and sensory properties of shrimp gamma irradiated with ⁶⁰Co at doses of 0, 1, 3, 6, 9 kGy were investigated. Irradiation at 6 kGy eliminated most of the spoilage microorganisms and did not affect sensory quality. The L* value increased as irradiation dose increased, while a* value decreased as irradiation dose increased. Irradiation had no significant effect on the texture of shrimp samples; however, increasing the dose up to 9 kGy significantly increased the amount of volatile compounds, such as, alcohols, ketones, aldehydes, furans, and oxides. According to the total sensory points, the appearance and flavour of the shrimp product was considered as acceptable by sensory evaluation when irradiated at doses of 0–6 kGy. These results showed that gamma irradiation processing (<6 kGy) had the potential to extend the shelf life of fried shrimp.     

Development and validation of an HPLC method for the determination of six penicillin and three amphenicol antibiotics in gilthead seabream (Sparus Aurata) tissue according to the European Union Decision 2002/657/EC

A confirmatory high performance liquid chromatography method for the determination of six penicillin antibiotics and three amphenicol antibiotics in gilthead seabream (Sparus Aurata) tissue was developed. Ampicillin (AMP), penicillin G (PG), penicillin V (PV), oxacillin (OXA), cloxacillin (CLO), dicloxacillin (DICLO), thiamphenicol (TAP), florfenicol (FFC) and chloramphenicol (CAP) were separated on an Inertsil, C₈ (250 × 4 mm, 5 μm) column by gradient elution with a mobile phase consisting of ammonium acetate 0.05 M and acetonitrile at 25 °C. Diode array detection with monitoring at 225 nm (for the determination of AMP, PG, PV, TAP and FFC), 240 nm (for OXA, CLO and DICLO) and 278 nm (for CAP) was applied. Examined antibiotics were isolated from gilthead seabream tissue by liquid–liquid extraction and further clean-up was performed by solid phase extraction using Oasis HLB (200 mg/6 mL) cartridges. The developed method was fully validated in terms of selectivity, linearity, accuracy, precision, stability and sensitivity according to the European Union Decision 2002/657/EC.     

Use of the relative dose response (RDR) assay to determine vitamin A status of calves at birth and four weeks of age

An accurate assessment of vitamin A status can be determined by analysis of liver biopsy samples; however, liver biopsies are not always feasible. Plasma concentrations of vitamin A do not provide an accurate indication of vitamin A status. The objective of this study, therefore, was to determine the ability of the relative dose response assay to indicate the vitamin A status of Holstein calves. Calves were obtained at birth and assigned to vitamin A treatments (0, 1700, 34,000, or 68,000 IU/d) added to milk replacer. Liver biopsies and relative dose response assays were performed at birth and 4 wk. Calves supplemented with 1700, 34,000, or 68,000 IU of vitamin A/d had adequate (greater than 20 microg/g) liver concentrations of vitamin A at 4 wk of age. The relative dose response assay at 4 wk was correlated with liver concentrations of vitamin A. Both the relative dose response assay and liver concentrations of vitamin A indicated that calves not supplemented with vitamin A had low vitamin A status, whereas other treatment groups had adequate vitamin A status. Plasma concentrations of retinol increased by 4 wk of age in calves receiving supplemental vitamin A at 34,000 IU and 68,000 IU/d and decreased in unsupplemented calves; however, all calves had concentrations of <20 microg of retinol/dl of plasma. The relative dose response assay agreed with liver biopsies as an indication of vitamin A status, whereas plasma concentrations of retinol incorrectly indicated all treatment groups were deficient in vitamin A.     

Validation of an analytical method for the determination of cadmium (Cd) in fish by atomic absorption spectrometry with electrothermal atomisation

The validation of an analytical method was carried out for the determination of cadmium (Cd) in fish. The method was based on sample digestion in a microwave oven and subsequent reading using an atomic absorption spectrometer with a graphite furnace. The factorial design of experiments was applied to assess method ruggedness using the methodology of Box et al. [Box GEP, Hunter WG, Hunter JS. 1978. Statistics for experiments: an introduction to design, data analysis and model building. New York (NY): Wiley], studying the influence of sample mass, volume and concentration of acid used for sample digestion and the volume of modifier used. To study the possible matrix effect in the determination of Cd, the standard addition method was also performed. The results were treated using the OLS method. For the normality test a homoskedastic distribution was observed for the developed method and the results were adjusted to the statistical model proposed. F-tests and Student's t-tests indicated that there was no matrix effect on the calibration curve between the concentration range 1.0-10.0 μg Cd l(-1). Parameters such as selectivity, precision, decision limit, detection capability and limit of quantification were established by the method of standard addition to blank samples. The limit of quantification was 6.8 μg kg(-1). Accuracy, which was evaluated by using a certified reference material, was 107.0%. The recovery of the spiked analyte was 93.69% for the concentration of 50 μg kg(-1). Precision was defined by the coefficient of variation observed (Horrat value), estimated in terms of repeatability and reproducibility, and the values were below the limit, which is 2.0. The validation procedure confirmed the suitability of the method.     

Microbiology of charcoal-broiled European river lampreys (Lampetra fluviatilis) stored at 3 and 22 degrees C

The microbiological quality of 30 production lots of charcoal-broiled river lampreys was studied at three lamprey processing plants (plants A, B, and C). Samples were taken directly after charcoal broiling and stored at 22 and 3 degrees C. Lampreys were examined on the day of manufacture, and those kept at 22 degrees C were examined every second day for 6 days. Samples kept at 3 degrees C were examined every fourth day for up to 24 days. On the production day, the mean aerobic plate counts (APCs) for broiled lampreys from plants A, B, and C were 2.29 log CFU/g, 1.88 log CFU/g, and undetectable (1.67 log CFU/g), respectively. At 22 degrees C, the mean APCs for samples from plants A, B, and C increased markedly within 4 days, and after 6 days the counts for samples from these plants were 8.56, 5.04, and 6.23 log CFU/g, respectively. Chilling and storage at 3 degrees C remarkably improved the shelf life of the product. The levels of bacteria in charcoal-broiled river lampreys from plant A were higher than those in lampreys from plants B and C. No significant increases in APCs were observed during storage at 3 degrees C for 24 days; mean APCs did not exceed 2.80 log CFU/g for samples from any plant. Staphylococcus aureus was found in two samples. No lactic acid bacteria, thermotolerant coliforms, enterococci, Clostridium perfringens, or Listeria monocytogenes was detected. Microbiological data from this study will be used for the development of a hazard analysis for the determination of critical control points.     

An intercomparison study of the determination of sulfite in tropical shrimps by the West European Fish Technologists’ Association (WEFTA)

Eight WEFTA laboratories participated in two series of intercomparison exercises on sulfite determination in tropical shrimps. Samples of tropical shrimps were spiked with sodium metabisulfite (Na₂S₂O₅) and hydroxymethylsulfonate (HMS) at a level of 25–90?mg SO₂/kg. Most of the laboratories determined the sulfite content with (modified) methods of Monier-Williams or De Vries et al. The overall mean recovery of sulfite was rather low (47–60%), which may be attributed to an irreversible reaction of sulfite with the tropical shrimps. The repeatability of the methods within the participating laboratories was good. However, reproducibility among the laboratries was poor. It has been shown that the sulfite content in tropical shrimps spiked with Na₂S₂O₅ decreased during storage at ?20°C and at +4°C. Hydroxymethyl- sulfonate was stable during storage.     

Development of a dielectric spectroscopy technique for the determination of apple (Granny Smith) maturity

Dielectric measurements of apple were done during its maturity in order to find relations with apple physiological compounds (sugar content, malic acid). An Agilent 85070E open-ended coaxial probe connected to an Agilent E8362B vector network analyzer were used in these experiments. All determinations were made at 30 °C from 500 MHz to 20 GHz. These assays were performed in order to consider the potential use of dielectric spectroscopy for determining the state of fruit maturity. Good correlations among apples Thiault Index with a new defined Dielectric Maturity Index were found. The Dielectric Maturity Index was related to loss factor at two punctual frequencies (0.5 GHz and dipolar relaxation frequency). This work is presenting a non-destructive control method for the prediction of climacteric fruits maturity.Industrial relevanceThe results of this research article are demonstrated to be useful for determining apple maturity. Thus, the industrial relevance is clear because the determination of fruit maturity is important to decide the best uses and storage time of the fruit. In the paper, a Maturity Index based on dielectric properties was developed. The results are obtained for the concrete application of apple fruit but they can be extended to other climacteric fruits although more studies are necessary. Dielectric spectroscopy, which can be considered an emerging technology, has the advantage of being an objective and a non destructive technique. For all these reasons we are sending to this journal “Innovative Food Science and Emerging Technologies” our results.     

A technique for the detection of low dose -irradiation in cooked Dutch shrimp (Crangon crangon) by disc protein patterns

Cooked and peeled shrimps were irradiated under air at levels of 50, 100 and 300 krad. Disc patterns of salt-extracted proteins of these samples showed a series of radio-characteristic effects. Based on these effects, a method for the detection of low dose irradiation has been developed. In addition, the applied dose can be estimated.     

Development of a low cost optimized handheld embedded odor sensing system (HE-Nose) to assess ripeness of oranges

Presented work addresses the development and application of artificial olfactory (e-nose) as an efficient nondestructive handheld system to extract quality attributes of variety of orange cultivars at various cultivated lands. An ARM-9 (S3C2440 controller) based advance embedded electronic nose system has been developed for on-site odor acquisition, processing and ripeness level prediction for various orange cultivars. Developed handheld electronic nose system is light weight, low power, and easy operable to every consumer. Various statistical multivariate data analysis techniques (PCA, LDA, QDA, and KNN) implementation on electronic nose measurements helped estimating optimal harvest dates for various orange cultivars. Developed handy system has been optimized in the sense of selectivity, sensitivity of gas sensors using the implementation of temperature control for heating element of the gas sensors. Various temperature, humidity models also have been developed to improve the performance of developed system in different environmental conditions. Data acquisition process has been performed using developed system for 100 orange samples have two different cultivars (mandarin and sweet orange). Extracted parameters have been subjected towards supervised Levenberg–Marquardt back-propagation algorithm to training and testing of developed handheld electronic nose system to predict quality parameters of oranges. A good correlation has been found between developed handheld electronic nose system signals and quality attributes indicators and it shows that system can successfully detect and predict various quality parameters of orange samples. Results of developed handheld electronic nose system have been validated with commercial standard electronic nose Alpha Fox 3000 system and it has been observed that efficiency varies around 94 ± 0.3 %.     

Novel application of an optical inspection system to determine the freshness of Scomber japonicus (mackerel) stored at a low temperature

Food Science and Biotechnology - This study evaluated the use of an optical inspection system (OIS) to determine the freshness of mackerel (Scomber japonicus). The correlations between the light...