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Prolamins are alcohol-soluble fraction of cereal proteins involved in immunological response of patients with celiac disease. The aim of this study was to analyse the similar protein complex of selected varieties of cereal, pseudocereal and legume grains by comparison of protein fractions, amino acids composition and SDS-PAGE electrophoresis. The immunoreactivity was tested by Western blot and ELISA methods. ELISA analysis recognizes celiac active epitopes in wheat gliadin (which is reference protein in determination of celiac activity), and also corresponding epitopes in other grain proteins responsible for immunological response of patients with celiac disease. Estimated quantity of celiac active sequences (calculated as gliadin content) below 20 ppm was found in species of amaranth, buckwheat and millet, as well as rice, maize, chickpea and chickling vetch. Immunological reaction with polyclonal antibody was negative for all crops, except oat, maize, millet and foxtail millet.
70 241 246 Andrews, J.L., Skerritt, J.H. 1996. Wheat dough extensibility screening using a two-site enzyme-linked immunosorbent assay (ELISA) with
A new liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed to confirm chloramphenicol (CAP) residues in foods of animal origin and in urine samples, which were earlier found positive under the screening analysis, performed by competitive enzyme-linked immunoassay (ELISA) technique. The developed LC-MS/MS method was applied to four non-compliant samples from 2008 to 2012; giving concentrations of CAP residues from 1.18 to 3.68 μg kg−1. All samples, qualified positive by ELISA, were confirmed with the LC-MS/MS technique and found to be non-compliant. The effectiveness of the confirmatory method was proven by participating in a successful proficiency test in year 2010. Both LC-MS/MS and ELISA methods were validated according to the European Union 2002/657/EC decision. The decision limit of the confirmatory method was determined as 0.02 μg kg−1 for CAP in each validated matrix, while the detection capability of the screening test was 0.15 μg kg−1.
Two indirect ELISAs for the detection of antibodies against glycoprotein E (gE) of Aujeszky's disease virus (ADV) in sera have been developed. The rec-gE-ELISA is based on theE. coli-expressed recombinant protein containing the N-terminal sequences of gE (aa 1-125) fused with the glutathione S-transferase fromSchistosoma japonicum. The affi-gE-ELISA is based on native gE, which was purified from virions by affinity chromatography. The tests were optimised and compared with each other, as well as with the recently developed blocking gE-ELISA (Morenkov et al., 1997b), with respect to specificity and sensitivity. The rec-gE-ELISA was less sensitive in detecting ADV-infected animals than the affi-gE-ELISA (sensitivity 80% and 97%, respectively), which is probably due to the lack of conformation-dependent immunodominant epitopes on the recombinant protein expressed inE. coli. The specificity of the rec-gE-ELISA and affi-gE-ELISA was rather moderate (90% and 94%, respectively) because it was necessary to set such cut-off values in the tests that provided a maximum level of sensitivity, which obviously increased the incidence of false positive reactions. Though the indirect ELISAs detect antibodies against many epitopes of gE, the blocking gE-ELISA, which detects antibodies against only one immunodominant epitope of gE, showed a better test performance (specificity 99% and sensitivity 98%). This is most probably due to rather high dilutions of the sera used in the indirect gE-ELISAs (1:30) as compared to the serum dilution in the blocking gE-ELISA (1:2). We conclude that the indirect gE-ELISAs are sufficiently specific and sensitive to distinguish ADV-infected swine from those vaccinated with gE-negative vaccine and can be useful, in particularly affi-gE-ELISA, as additional tests for the detection of antibodies to gE.
Small ruminant lentiviruses (SRLV) are spread throughout the world, including Slovenia, where the first evidence of caprine arthritis encephalitis virus (CAEV) infection was found in 1996. This study was conducted to investigate the molecular and genetic characteristics of SRLV infection in Slovenia in order to classify our strains in relation to other known SRLV strains worldwide as well as to establish molecular techniques in concordance with serology. In this study, 340 goats and sheep were tested. Serological examination revealed that 57% of the goats and only 14% of the sheep were seropositive. The results of this study also show that the polymerase chain reaction (PCR) used in this study is less reliable than ELISA, with only 60.6% of the seropositive animals being PCR positive. Thirty-eight nucleotide sequences of the gag region encoding the matrix protein were determined and compared to sequences derived from the GenBank, revealing that Slovenian SRLV strains belong to sequence groups A and B, being maedivisna virus (MVV) and CAEV-like, respectively. In one goat herd, the presence of more than one genotype was confirmed and the majority of goat SRLV sequences were more closely related to MVV than to CAEV prototype strains.
Successful applications of toxins derived from Bacillus thuringiensis (Bt) strains in Bt-based bioinsecticides and more recently in Bt-plants in crop protection have enhanced the importance of analytical quantification of Cry toxin dosages for studies on various topics including environmental risk assessment (ERA), resistance management, quality control and regulatory compliance. It is essential to follow-up distribution and environmental degradation of these lectin type, crystalline (Cry) toxin proteins showing insect specificity at order level. Thus, Cry1Ab toxin produced by Bt-maize of genetic event MON 810 is specific to lepidopteran species. Widely used analytical methods for detection of Cry toxins are enzyme-linked immunosorbent assay (ELISA) systems. Reported Cry1Ab toxin concentrations in MON 810 maize show high variability: order of magnitude differences have been observed among various plant parts from different varieties, cultivated at different locations, and sometimes even within the same plant variety at a single location. Besides biological sources of variability, numerous analytical problems have been identified and are reported in this report, influencing the results of quantitative determination of Cry1Ab toxin and explaining the high variability among documented data on toxin content. Conclusions in every case refer to genetic event MON 810, but can be extended to other genetic events producing Cry1Ab toxin.
A new necrosis viral disease was observed in blackgram, showed brown necrotic rings along with veinal and stem necrosis. The virus was mechanically inoculated on the local lesion host, cowpea cv. 152 and maintained in the local lesion host throughout the study. Yield studies under pot culture experiment showed 10- to 30-day-old plants were highly susceptible and the yield became almost nil. By using Transmission Electron Microscope (TEM) and indirect Direct Antigen Coated-Enzyme Linked Immuno-Sorbent Assay (DAC-ELISA) studies the virus was identified as Tobacco streak virus (TSV). The ultraviolet absorbance of the purified virus was measured and the ratio of A260/A280 was determined as 1.41. Polyclonal antiserum was raised against blackgram necrosis virus in New Zealand white rabbit and the titre value was determined as 1: 200. Direct antigen coating-ELISA was used to detect the virus concentration in various plant parts and stem portion recorded maximum virus concentration. TSV in blackgram was not transmitted through seeds.
Asprosin levels in the blood sera were determined using a commercial enzyme-linked immunosorbent assay (ELISA) kit (Sunred Bovine Asprosin Kit, Shanghai) and an ELISA reader (Bio Tek Instruments, USA) as described by Ugur and Aydin (2019
The current work reports the ochratoxin A (OTA) levels in 23 food (bread, dried fruit, pulse) and beverage (black tea, coffee) products commonly consumed in Turkey determined with ELISA. OTA levels in kidney bean, haricot bean, and red lentil samples from Turkey were investigated for the first time in this study. The highest OTA levels were detected in instant coffee (158.9 μg kg–1), black tea (139.5 μg kg–1), and filter coffee (118.4 μg kg–1) samples. Of the tested samples, 78.27% exceeded legal limits of OTA. These results support the existing knowledge that food and beverages should be regularly and effectively controlled to protect human health.
PCV2 and PRRSV are two important pathogens of domestic swine. There is considerable evidence that the infection is also present in wild boars. Meat juice provides an alternative to serum for antibody testing, and it has been used in testing for many important porcine infectious diseases. Samples of brachial muscle were collected from 142 wild boars shot in different regions of Poland during the 2006/2007 and 2007/2008 hunting seasons. Meat juice harvested from muscle samples was tested using an ELISA test specific for PCV2 and PRRSV antibodies. Additionally, IgG and IgM antibodies specific for PCV2 were detected in order to estimate the status of the PCV2 infection. Only one of the tested meat juice samples was positive for PRRSV (0.7%), and 68 out of 142 (47.9%) samples were positive for PCV2. Of the positive animals, 4 (2.8%) had an antibody profile suggesting active infection, 2 (1.4%) early active infection, and 62 (43.7%) late infection. Also, a lack of association between the age of the animals and the presence of antibodies related to the infection was noticed.
