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Stefan Vieths - One of the best experts on this subject based on the ideXlab platform.

  • Protein quantification, sandwich ELISA, and real-time PCR used to monitor industrial cleaning procedures for contamination with peanut and Celery allergens
    Journal of AOAC International, 2004
    Co-Authors: Oliver Stephan, Thomas Weiser, Nathan Weisz, Burghard Rabe, Stefan Vieths, Wolfgang Vatterott
    Abstract:

    In the United States, peanut is one of the main sources of food allergens. Similarly, Celery is a common allergenic food in Western Europe. Severe allergic reactions to both foods are common. Unexpected allergic reactions can occur after the consumption of Celery- and peanut-free foods as a result of inadvertent cross-contaminations during manufacturing. Therefore, in cooperation with a flavor manufacturer, we monitored the cleaning process of slurry preparation equipment with regard to contaminations of follow-up products with Celery and peanut compounds. Washing water samples taken after different cleaning steps and follow-up products were analyzed for the presence of Celery and peanut traces with a Celery-specific real-time polymerase chain reaction (PCR) and a peanut-specific sandwich enzyme-linked immunosorbent assay (ELISA). PCR and ELISA were compared with a nonspecific protein assay to evaluate whether the detection of protein traces can be a fast and cost-effective method for monitoring the effectiveness of wet cleaning procedures. Additionally, the allergenic potential of the Celery and peanut mush, which were used as source material, were measured by a mediator release assay using a rat basophilic leukemia (RBL) cell line. In conclusion, the quantification of total protein in washing water was suitable for monitoring the cleaning process. Our study also revealed evidence that, in cases where wet cleaning is applicable, allergenic traces can be removed with high efficiency.

  • influence of food processing on the allergenicity of Celery dbpcfc with Celery spice and cooked Celery in patients with Celery allergy
    Allergy, 2002
    Co-Authors: Barbara Ballmerweber, B Wuthrich, Andreas Hoffmann, D Luttkopf, C Pompei, Andrea Wangorsch, Marion Kastner, Stefan Vieths
    Abstract:

    BACKGROUND: Celery root is often consumed in a processed form as a cooked vegetable or as a spice. So far, however, there has been no information about the allergenicity of processed Celery in Celery-allergic patients. METHODS: In 12 patients with a history of allergic reactions to raw or raw and cooked Celery, double-blind placebo-controlled food challenges (DBPCFCs) with raw Celery (n = 10), cooked Celery (110 degrees C/15 min; n = 11), and Celery spice (n = 5) were performed. Nine patients underwent an open mucosal challenge with four samples of canned Celery retorted at Co-values (cooking effect) of 7.45-76.07 (corresponding to the time periods in minutes at a thermal influence of 100 degrees C). IgE immunoblot analysis of Celery extract was performed with sera of all challenged patients. The thermal stability of Celery allergen was investigated by enzyme allergosorbent test (EAST) inhibition. Furthermore, intraperitoneal immunization of mice followed by a rat basophil leukemia (RBL) cell mediator release assay was used as a biological in vitro model to assess the allergenicity of processed Celery. RESULTS: Six out of 11 patients showed a positive DBPCFC to cooked Celery and five out of five patients to Celery spice. Allergenicity of Celery was preserved in four patients with a positive DBPCFC to cooked Celery even if Celery was treated at a Co-value of 76.07. Patients with positive DBPCFC to cooked Celery reacted to known Celery allergens (Api g 1, Api g 4, cross-reactive carbohydrate determinants CCD). EAST inhibition showed that heat resistance of Celery allergens decreases in the following order: CCD > Api g 4 > Api g 1. Accordingly, five of six patients with a positive DBPCFC to cooked Celery were sensitized to profilin and/or CCD. The murine model reflected the reactivity of patients sensitized to the major allergen Api g 1. CONCLUSIONS: 1) In a subset of patients with a positive DBPCFC to cooked Celery, Celery remains allergenic even after extended thermal treatment (76.07 min/100 degrees C). 2) Celery spice is allergenic for patients with an allergy to raw Celery. 3) RBL cells sensitized with mouse IgE to raw Celery may serve as a useful tool for screening the potential allergenicity of heat-processed products containing Celery.

  • Celery allergy confirmed by double blind placebo controlled food challenge a clinical study in 32 subjects with a history of adverse reactions to Celery root
    The Journal of Allergy and Clinical Immunology, 2000
    Co-Authors: Barbara Ballmerweber, Stefan Vieths, D Luttkopf, Pascale Heuschmann, B Wuthrich
    Abstract:

    Abstract Background: Celery root is a frequent cause of food allergy in pollen-sensitized patients. Because of problems in blinding challenges with fresh vegetables and the risk of anaphylactic reactions, no double-blind, placebo-controlled, food challenges (DBPCFCs) with Celery have been published so far. Objective: The aim of the study was to confirm the clinical relevance of Celery as a food allergen by DBPCFCs and to evaluate current diagnostic procedures in patients with true allergy. Methods: DBPCFCs were performed in 32 patients with a history of an allergic reaction to Celery. The patients underwent skin prick tests (SPTs) with Celery extracts, crude Celery, and different pollen extracts. Specific IgE for Celery was determined by using the CAP method. Results: Twenty-two of 32 patients had a positive DBPCFC result. Two patients reacted to placebo, and 8 patients did not respond to the challenge. Of the nonresponders, 4 reacted to an open provocation with Celery. The sensitivity of CAP determination for specific IgE (≥0.7 kU/L) to Celery in patients with a positive DBPCFC result was 73%, 48% to 86% for SPTs (≥3 mm) with commercial extracts, and 96% for prick-to-prick tests with crude Celery. The positive predictive value of the SPT and CAP tests was between 87% and 96%, whereas the specificity and negative predictive values were poor. Conclusion: This study confirms the importance of Celery as a food allergen for use in DBPCFCs. The SPT and CAP methods proved to be reliable for the diagnosis of a relevant allergy to Celery in regard to sensitivity and positive predictive value but not to specificity and negative predictive value. (J Allergy Clin Immunol 2000;106:373-8.)

  • Celery allergens in patients with positive double blind placebo controlled food challenge
    The Journal of Allergy and Clinical Immunology, 2000
    Co-Authors: D Luttkopf, Brunello Wüthrich, Barbara K Ballmerweber, Stefan Vieths
    Abstract:

    Abstract Background: Recently, for the first time, allergy to Celery was confirmed by double-blind placebo-controlled food challenge (DBPCFC). Api g 1, Api g 4, cross-reactive carbohydrate determinants (CCD), and a 60 kDa allergen have been described as Celery allergens. Objective: To get insights in IgE responses of patients with a positive DBPCFC to Celery tuber (celeriac) compared with patients with a negative challenge test. Methods: Specific IgE to native and heated Celery tuber and to recombinant Api g 1, the major Celery allergen, were determined by enzyme allergosorbent test and immunoblotting. IgE binding to Api g 1, Api g 4, and CCD was confirmed by inhibition experiments that used recombinant Api g 1, recombinant Api g 4, pure N-glycans, and extracts of celeriac, lychee fruit, and pollens of birch, mugwort, and timothy grass as inhibitors. Results: Immunoblotting with sera from 22 patients with a positive DBPCFC to celeriac confirmed the presence of known allergenic structures: The major allergen Api g 1 (16 kDa) was recognized by IgE from 13 of 22 patients (59%). Another major allergen was CCD, determined by IgE reactivity in 12 of 22 patients (55%). Celery profilin, Api g 4, was recognized by IgE from 5 of 22 patients (23%). Conclusion: Our DBPCFC-positive patients exclusively presented IgE to known Celery allergens, although the prevalences were slightly different than were previously reported. No obvious differences were found in patients with positive IgE antibody but negative challenge test. IgE binding to all 3 structures in celeriac extract was inhibited by birch pollen extract, whereas mugwort pollen extract could only inhibit IgE reactivity to Api g 4 and CCD. Inhibition experiments with a purified carbohydrate moiety clearly showed that the IgE epitope mannose-xylose-fucose-glycan (Manα1-6[Xylβ1-2]Manβ1-4GlcNAcβ1-4[Fucα1-3]GlcNAc) or a closely related structure is present in celeriac extract and is important in patients with clinical allergy to Celery. (J Allergy Clin Immunol 2000;106:390-9.)

Remi Lemoine - One of the best experts on this subject based on the ideXlab platform.

  • identification of a mannitol transporter agmat1 in Celery phloem
    The Plant Cell, 2001
    Co-Authors: Nathalie Noiraud, Laurence Maurousset, Remi Lemoine
    Abstract:

    A Celery petiole phloem cDNA library was constructed and used to identify a cDNA that gives Saccharomyces cerevisiae cells the ability to grow on mannitol and transport radiolabeled mannitol in a manner consistent with a proton symport mechanism. This cDNA was named AgMaT1 (Apium graveolens mannitol transporter 1). The expression profile in source leaves and phloem was in agreement with a role for mannitol in phloem loading in Celery. The identification in eukaryotes of a mannitol transporter is important because mannitol is not only a primary photosynthetic product in species such as Celery but is also considered a compatible solute and antioxidant implicated in resistance to biotic and abiotic stress.

  • the sucrose transporter of Celery identification and expression during salt stress
    Plant Physiology, 2000
    Co-Authors: Nathalie Noiraud, Serge Delrot, Remi Lemoine
    Abstract:

    In Celery ( Apium graveolens L.), long-distance transport of reduced carbon occurs both in the form of sucrose (Suc) and mannitol. The presence of mannitol has been related to the resistance of Celery to salt stress. To investigate the transport events occurring during salt stress, we have cloned the H + /Suc transporter of Celery AgSUT1 ( A. graveolens Suc uptake transport 1) from a mature leaf cDNA library. The function of the encoded protein was confirmed by expression in yeast. AgSUT1 is a H + /Suc transporter with a high affinity for Suc ( K m of 139 μm). Another closely related cDNA ( AgSUT2) was also identified. AgSUT1 is mainly expressed in mature leaves and phloem of petioles, but also in sink organs such as roots. When Celery plants were subjected to salt stress conditions (30 d watering with 300 mm NaCl) favoring mannitol accumulation (J.D. Everard, R. Gucci, S.C. Kann, J.A. Flore, W.H. Loescher [1994] Plant Physiol 106: 281–292), AgSUT1 expression was decreased in all organs, but markedly in roots. The results are discussed in relation to the physiology of Celery.

Maria M Lopez - One of the best experts on this subject based on the ideXlab platform.

  • association of candidatus liberibacter solanacearum with a vegetative disorder of Celery in spain and development of a real time pcr method for its detection
    Phytopathology, 2014
    Co-Authors: Gabriela R Teresani, Edson Bertolini, A Alfarofernandez, Carmen Martinez, Francisco Andre Ossamu Tanaka, E W Kitajima, M Rosello, Susana Sanjuan, Juan Carlos Ferrandiz, Maria M Lopez
    Abstract:

    ABSTRACT A new symptomatology was observed in Celery (Apium graveolens) in Villena, Spain in 2008. Symptomatology included an abnormal amount of shoots per plant and curled stems. These vegetative disorders were associated with ‘Candidatus Liberibacter solanacearum’ and not with phytoplasmas. Samples from plant sap were immobilized on membranes based on the spot procedure and tested using a newly developed real-time polymerase chain reaction assay to detect ‘Ca. L. solanacearum’. Then, a test kit was developed and validated by intralaboratory assays with an accuracy of 100%. Bacterial-like cells with typical morphology of ‘Ca. Liberibacter’ were observed using electron microscopy in Celery plant tissues. A fifth haplotype of ‘Ca. L. solanacearum’, named E, was identified in Celery and in carrot after analyzing partial sequences of 16S and 50S ribosomal RNA genes. From our results, Celery (family Apiaceae) can be listed as a new natural host of this emerging bacterium.

Zhifang Yu - One of the best experts on this subject based on the ideXlab platform.

  • preservation of fresh cut Celery by treatment of ozonated water
    Food Control, 2005
    Co-Authors: Likui Zhang, Zhaoxin Lu, Zhifang Yu
    Abstract:

    Abstract Fresh-cut Celery was dipped with ozonated water and evaluated for changes of microbiological population and physiological quality during storage at 4 °C. The polyphenoloxidase (PPO) activity and respiration rate of fresh-cut Celery was much inhibited by treatment of ozonated water and sensory quality of fresh-cut Celery treated with ozonated water was better (α=0.05) than that of non-treated. However, there is no significant difference (α=0.05) between Vitamin C and total sugar of fresh-cut Celery treated with ozonated water and non-treated. The best effect of preservation of fresh-cut Celery appeared to be the treatment of water ozonated to a 0.18 ppm of concentration, with which the microbial population was lowered to 1.69 LogCFU/g.

G Muratore - One of the best experts on this subject based on the ideXlab platform.

  • effects of packaging on shelf life of fresh Celery
    Journal of Food Engineering, 2009
    Co-Authors: V Rizzo, G Muratore
    Abstract:

    Abstract Celery could be sold in a wide range of presentations, from without any kind of packaging until ‘ready to eat’. The aim of this research was to analyse the effect of two packaging films on quality loss of Celery due to frequent changes in temperature and relative humidity as well as to varying respiration rates. Shelf life could be extended by limiting storage temperature variations. Weight loss, discoloration and texture changes appear to be the primary symptoms for deterioration in quality. Celery stalks were packed in polyolefin (co-extruded polyethylene and polypropylene) with an antifogging additive (AF) and micro perforated polypropylene (MP). Samples were kept at 4 ± 1 °C, 90% RH for 35 days, using unpacked Celery as control. Weight loss, firmness, pH, soluble solid content, titratable acidity, petioles and leaves colour, and total phenols were determined. The results showed that colour intensity and firmness decreased during storage; weight loss in AF packed Celery was lower than 3%. Tiny accumulations of condensate in AF didn’t reduce shelf life, so it may be considered the most suitable packaging material for extending shelf life of Celery stalks.