Screening for Clostridium botulinum Type A, B, and E in Cooked Chilled Foods Containing Vegetables and Raw Material Using Polymerase Chain Reaction and Molecular Probes

2001 ◽  
Vol 64 (2) ◽  
pp. 201-207 ◽  
Author(s):  
AGNÈS BRACONNIER ◽  
VÉRONIQUE BROUSSOLLE ◽  
SYLVIE PERELLE ◽  
PATRICK FACH ◽  
CHRISTOPHE NGUYEN-THE ◽  
...  

A molecular method was used for the detection of Clostridium botulinum spores of type A, B, and E in commercial cooked and pasteurized vegetable purées and in the raw materials (vegetables and other ingredients). The method allowed the detection of less than 8 spores/g of product for C. botulinum type A, less than 1 spore/g for proteolytic type B, less than 21 spores/g for nonproteolytic type B, and less than 0.1 spore/g for type E. Thirty-seven samples of raw vegetables and ingredients were tested for the presence of C. botulinum type A, B, and E; 88 and 90 samples of vegetable purées were tested, respectively, for the presence of C. botulinum type A and B and for the presence of C. botulinum type E. All samples were negative, suggesting that the prevalence of C. botulinum in these vegetable purées and the raw ingredients is probably low.

1994 ◽  
Vol 8 (5) ◽  
pp. 365-373 ◽  
Author(s):  
Joseph L. Ferreira ◽  
Mostafa K. Hamdy ◽  
Steven G. McCay ◽  
Mark Hemphill ◽  
Nameer Kirma ◽  
...  

Blood ◽  
1993 ◽  
Vol 81 (12) ◽  
pp. 3372-3381 ◽  
Author(s):  
JC Lin ◽  
SC Lin ◽  
BK De ◽  
WC Chan ◽  
BL Evatt ◽  
...  

Abstract To precisely determine the genotype of Epstein-Barr virus (EBV) in Hodgkin's disease (HD), we simultaneously analyzed three divergent gene loci (EBNA-2, EBNA-3C, and EBER) that distinguish type A and B viruses. The primers designed to amplify these three gene loci encompass either type-specific deletion sequences (EBNA-2 and EBNA-3C) or type-specific point mutations (EBER) that identify the virus strain based on the sizes of the polymerase chain reaction (PCR)-amplified products or the mobility shifts in single-strand conformation polymorphism analysis. The locations of point mutations were identified by direct sequencing of the PCR-amplified DNA. We analyzed 15 EBV-infected cell lines and found a good correlation between EBNA-2 and EBNA-3C typing results. In contrast, approximately 33% of the cell lines analyzed maintained type A sequences in EBNA-2 and EBNA-3C genes while carrying type B sequences in the EBER region. Data obtained from analysis of cell lines served as a reference for studying HD samples. EBV DNA was detected in about 70% of HD. Among the EBV-positive samples, 56% were associated with type A virus, 13% with type B, and 31% with dual viral sequences. Thus, type A virus is predominant in HD. Based on the histology, the frequencies of EBV positivity were 83%, 71%, and 33% for mixed cellularity, nodular sclerosis, and lymphocyte predominance, respectively. The detection of high frequency of both type A and B sequences in HD may provide a lead in investigating the role of dual viral infection in EBV pathogenesis.


Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1091
Author(s):  
Alexandra Inberg ◽  
Dana Ashkenazi ◽  
Yishai Feldman ◽  
Omri Dvir ◽  
Deborah Cvikel

Fragments of decorated floor tiles were retrieved from the Akko Tower shipwreck, Israel. Most tiles were made of bright brown fired clay with a white glaze decorated with colored stenciled motifs (Type A); and others consisted of a red-brown fired clay body, coated with a brown pigment covered with transparent brown glaze (Type B). This study aimed to characterize the two tile types; to reveal information concerning the manufacturing process; and to determine the origin of their raw material. A multidisciplinary approach was used, including light microscopy, SEM-EDS, electron probe microanalysis with wavelength-dispersive X-ray spectroscopy (EPMA-WDS), XRD, Raman spectroscopy, and time-of-flight secondary ion mass spectrometry (TOF-SIMS) analyses. The characterization of both tile types demonstrated the use of different raw materials. The Type A tiles were covered with tin-opacified majolica glaze and colored with various mixtures of pigments. The blue color was due to pigment rich in cobalt; the yellow color was due to Naples yellow and lead-tin yellow I minerals; and the green, orange, and brown colors were all prepared by mixing the Naples yellow pigment with different minerals. These majolica glaze tiles were probably manufactured in Sicily. The brown coating of the Type B tiles was due to pigment rich in lead and iron minerals. These tiles were produced with different manufacturing processes, and apparently made in France.


2013 ◽  
Vol 76 (8) ◽  
pp. 1384-1392 ◽  
Author(s):  
N. RUKMA REDDY ◽  
KRISTIN M. MARSHALL ◽  
TRAVIS R. MORRISSEY ◽  
VIVIANA LOEZA ◽  
EDUARDO PATAZCA ◽  
...  

The aim of this study was to determine the resistance of multiple strains of Clostridium botulinum type A and proteolytic type B spores exposed to combined high pressure and thermal processing and compare their resistance with Clostridium sporogenes PA3679 and Bacillus amyloliquefaciens TMW-2.479-Fad-82 spores. The resistance of spores suspended in N-(2-acetamido)-2-aminoethanesulfonic acid (ACES) buffer (0.05 M, pH 7.0) was determined at a process temperature of 105°C, with high pressures of 600, 700, and 750 MPa by using a laboratory-scale pressure test system. No surviving spores of the proteolytic B strains were detected after processing at 105°C and 700 MPa for 6 min. A >7-log reduction of B. amyloliquefaciens spores was observed when processed for 4 min at 105°C and 700 MPa. D-values at 105°C and 700 MPa for type A strains ranged from 0.57 to 2.28 min. C. sporogenes PA3679 had a D-value of 1.48 min at 105°C and 700 MPa. Spores of the six type A strains with high D-values along with C. sporogenes PA3679 and B. amyloliquefaciens were further evaluated for their pressure resistance at pressures 600 and 750 MPa at 105°C. As the process pressure increased from 600 to 750 MPa at 105°C, D-values of some C. botulinum strains and C. sporogenes PA3679 spores decreased (i.e., 69-A, 1.91 to 1.33 min and PA3679, 2.35 to 1.29 min). Some C. botulinum type A strains were more resistant than C. sporogenes PA3679 and B. amyloliquefaciens to combined high pressure and heat, based on D-values determined at 105°C. Pulsed-field gel electrophoresis (PFGE) was also performed to establish whether strains with a similar restriction banding pattern also exhibited similar D-values. However, no correlation between the genomic background of a strain and its resistance to high pressure processing was observed, based on PFGE analysis. Spores of proteolytic type B strains of C. botulinum were less resistant to combined high pressure and heat (700 MPa and 105°C) treatment when compared with spores of type A strains.


Blood ◽  
1993 ◽  
Vol 81 (12) ◽  
pp. 3372-3381 ◽  
Author(s):  
JC Lin ◽  
SC Lin ◽  
BK De ◽  
WC Chan ◽  
BL Evatt ◽  
...  

To precisely determine the genotype of Epstein-Barr virus (EBV) in Hodgkin's disease (HD), we simultaneously analyzed three divergent gene loci (EBNA-2, EBNA-3C, and EBER) that distinguish type A and B viruses. The primers designed to amplify these three gene loci encompass either type-specific deletion sequences (EBNA-2 and EBNA-3C) or type-specific point mutations (EBER) that identify the virus strain based on the sizes of the polymerase chain reaction (PCR)-amplified products or the mobility shifts in single-strand conformation polymorphism analysis. The locations of point mutations were identified by direct sequencing of the PCR-amplified DNA. We analyzed 15 EBV-infected cell lines and found a good correlation between EBNA-2 and EBNA-3C typing results. In contrast, approximately 33% of the cell lines analyzed maintained type A sequences in EBNA-2 and EBNA-3C genes while carrying type B sequences in the EBER region. Data obtained from analysis of cell lines served as a reference for studying HD samples. EBV DNA was detected in about 70% of HD. Among the EBV-positive samples, 56% were associated with type A virus, 13% with type B, and 31% with dual viral sequences. Thus, type A virus is predominant in HD. Based on the histology, the frequencies of EBV positivity were 83%, 71%, and 33% for mixed cellularity, nodular sclerosis, and lymphocyte predominance, respectively. The detection of high frequency of both type A and B sequences in HD may provide a lead in investigating the role of dual viral infection in EBV pathogenesis.


1994 ◽  
Vol 57 (10) ◽  
pp. 878-881 ◽  
Author(s):  
HAIM M. SOLOMON ◽  
E. JEFFERY RHODEHAMEL ◽  
DONALD A. KAUTTER

The ability of Clostridium botulinum type A or B spores to grow and produce toxin in fresh raw potatoes under vacuum with or without sulfite at 22°C was investigated. Fresh, peeled, sliced potatoes, untreated or dipped for 2 min in sulfite (NaHSO3) and drained, were surface-inoculated at several levels with a mixture of C. botulinum spores, either type A or B, and placed in oxygen-impermeable bags (200 g/bag) that were then vacuum-sealed and incubated at room temperature (22°C). Toxicity was tested on days 0, 3, 4, 5 and 6. After incubation, the potatoes were blended and centrifuged, and the millipore-filtered supernatant fluid was injected intraperitoneally into mice. Sensory evaluation, except taste, was also performed. Potatoes inoculated with C. botulinum type A spores, but untreated with NaHSO3 became toxic in 3 days, which coincided with the sensory evaluation, “Unfit for human consumption.” However, despite inoculum size or residual SO2 levels, potatoes treated with NaHSO3 appeared acceptable for human consumption through day 6, even though they were toxic after 4 days of incubation. Toxicity from type B spores occurred later and in fewer test samples than type A. Again, the potatoes appeared acceptable but were toxic. Thus, although NaHSO3 markedly extended the consumer acceptability of peeled, sliced, raw potatoes at the abuse temperature, it did not inhibit outgrowth and toxin production by C. botulinum under these same conditions.


1988 ◽  
Vol 51 (11) ◽  
pp. 862-865 ◽  
Author(s):  
HAIM M. SOLOMON ◽  
DONALD A. KAUTTER

The ability of Clostridium botulinum types A and B spores to grow and produce toxin in commercially bottled chopped garlic in soybean oil was investigated. Eight type A and seven type B strains of C. botulinum, mostly of vegetable origin, were used as inocula. Various numbers of spores were inoculated directly into the jars containing garlic, incubated at 35°C and sampled for organoleptic acceptance and presence of toxin every 5th d. In parallel studies conducted at room temperature, jars were sampled at 15-d intervals. At 35°C, when 1 spore/g of garlic was used as inoculum, toxin was produced in 15 d by type A and in 20 d by type B strains. At room temperature, five spores of type A or B per g of garlic produced toxin throughout 75 d. Even when highly toxic, garlic looked and smelled acceptable. Five strains of C. botulinum type A were isolated from 115 bulbs of fresh garlic.


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