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A C Scoging

Publications and source records attributed to A C Scoging.

6 recordsLinked to original sources

Evaluation of methods for recognising strains of the Bacillus cereus group with food poisoning potential among industrial and environmental contaminants.

Toxin production, biochemical properties and ribotypes of Bacillus cereus group (B. cereus, B. thuringiensis, B. mycoides) strains originating from industrial and environmental sources (n = 64), from food poisoning incidents (n = 22) and from reference sources (n = 7) were analysed. Forty ribotypes were found among the 93 strains. Eleven strains from food poisoning incidents produced emetic (mitochondrio) toxin, as determined by the boar spermatozoa toxicity test. These strains possessed closely similar ribotypes which were rare among strains of other origins. Sperm toxin producing (cereulide positive) strains did not hydrolyse starch and did not produce haemolysin BL, as determined by the reverse passive latex agglutination test. Sixteen different ribotypes were found among B. cereus strains from board machines (n = 16) and from packaging board (n = 16), indicating many different sources of B. cereus contamination in board mills. Strains originating from packaging board had predominantly different ribotypes from those of dairy and dairy product originating strains. Nine (53%) out of 17 strains from a single dairy process shared the same ribotype whereas strains from milk and milk products from different dairies had different ribotypes indicating that B. cereus group populations were dairy specific. Twenty-two percent of strains isolated from the paperboard industry on non-selective medium were lecithinase negative, including enterotoxin producing strains. This stresses the importance of other detection methods not based on a positive lecithinase reaction.

Bacillus cereus↗

Toxigenic strains of Bacillus licheniformis related to food poisoning.

Toxin-producing isolates of Bacillus licheniformis were obtained from foods involved in food poisoning incidents, from raw milk, and from industrially produced baby food. The toxin detection method, based on the inhibition of boar spermatozoan motility, has been shown previously to be a sensitive assay for the emetic toxin of Bacillus cereus, cereulide. Cell extracts of the toxigenic B. licheniformis isolates inhibited sperm motility, damaged cell membrane integrity, depleted cellular ATP, and swelled the acrosome, but no mitochondrial damage was observed. The responsible agent from the B. licheniformis isolates was partially purified. It showed physicochemical properties similar to those of cereulide, despite having very different biological activity. The toxic agent was nonproteinaceous; soluble in 50 and 100% methanol; and insensitive to heat, protease, and acid or alkali and of a molecular mass smaller than 10,000 g mol(-1). The toxic B. licheniformis isolates inhibited growth of Corynebacterium renale DSM 20688(T), but not all inhibitory isolates were sperm toxic. The food poisoning-related isolates were beta-hemolytic, grew anaerobically and at 55 degrees C but not at 10 degrees C, and were nondistinguishable from the type strain of B. licheniformis, DSM 13(T), by a broad spectrum of biochemical tests. Ribotyping revealed more diversity; the toxin producers were divided among four ribotypes when cut with PvuII and among six when cut with EcoRI, but many of the ribotypes also contained nontoxigenic isolates. When ribotyped with PvuII, most toxin-producing isolates shared bands at 2.8 +/- 0.2, 4.9 +/- 0.3, and 11.7 +/- 0.5 or 13.1 +/- 0.8 kb.

Animals↗

Comparison of a protein phosphatase inhibition assay, HPLC assay and enzyme-linked immunosorbent assay with the mouse bioassay for the detection of diarrhetic shellfish poisoning toxins in European shellfish.

Consumption of shellfish contaminated with algal toxins produced by marine dinoflagellates can lead to diarrhetic shellfish poisoning (DSP). UK legislation necessitates toxin detection by mouse bioassay but this method is non-specific and lacks sensitivity. As an alternative method, an HPLC technique has been optimized, with detection limits of 0.26 micrograms of toxin/g of shellfish hepatopancreas for both Okadaic Acid (OA) and Dinophysistoxin-1 (DTX-1). A colorimetric protein phosphatase inhibition (PPI) assay has also been optimized. This assay detects inhibition of protein phosphatase 1 (PPI gamma) by OA and DTX-1 with detection limits of 1.5 ng of total toxin/g of hepatopancreas. Contaminated shellfish from several European sources, the UK monitoring programmes and mussels associated with an outbreak of DSP poisoning in the UK, have been analyzed and assessed using the two alternative methods and a commercially available enzyme-linked immunosorbent assay (ELISA) kit. The results indicate that both the HPLC and PPI assays correlate well with each other and with the UK standard mouse bioassay. In contrast, and not withstanding its advantages of rapidity and ease, the ELISA kit did not accurately and consistently detect low toxin concentrations, although it may be useful as a screening tool.

Animals↗

Fulminant liver failure in association with the emetic toxin of Bacillus cereus.

BACKGROUND: A 17-year-old boy and his father had acute gastroenteritis after eating spaghetti and pesto that had been prepared four days earlier. Within two days, fulminant liver failure and rhabdomyolysis developed in the boy and he died. The father had hyperbilirubinemia and rhabdomyolysis but recovered. We investigated the cause of these illnesses. METHODS: Bacteria were isolated and characterized by conventional methods, and bacterial toxins were quantified by immunoassays and cell-culture techniques. The effect of the isolated toxin on the rates of oxidation of various substrates was analyzed in rat-liver mitochondria. RESULTS: Autopsy of the boy's liver revealed diffuse microvesicular steatosis and midzonal necrosis that suggested impaired beta-oxidation of liver mitochondria due to a mitochondrial toxin. There was no evidence of ingestion of heavy metals, halogenated compounds, hepatotoxic drugs, or staphylococcal enterotoxin. However, high concentrations of Bacillus cereus emetic toxin were found in both the residue from the pan used to reheat the food and the boy's liver and bile. B. cereus was cultured from the intestinal contents and the pan residue. The emetic toxin isolated from the B. cereus cultures was found to be a mitochondrial toxin. CONCLUSIONS: Fulminant liver failure developed after the ingestion of food contaminated with the B. cereus emetic toxin. The toxin inhibits hepatic mitochondrial fatty-acid oxidation, indicating that it caused liver failure in this patient.

Adolescent↗

Illness associated with seafood.

Seafood is a common vehicle for the transmission of infections and intoxications. The main concerns in the UK are scombroid fish poisoning, viral infections (associated with bivalve molluscs) and bacterial infections (associated with crustaceans). Paralytic shellfish poisoning (PSP) and red whelk poisoning occur sporadically, and ciguatera has started to appear associated with imported fish. The appearance in coastal waters of marine algae associated with diarrheic shellfish poisoning (DSP) has increased the likelihood of outbreaks of this toxic syndrome. The dinoflagellates causing neurotoxic shellfish poisoning and amnesic shellfish poisoning have not been detected in UK fishing waters but the fluctuating distribution of algal populations makes their appearance a possibility. The Food Hygiene Laboratory and the Torry research station of the Ministry of Agriculture, Fisheries and Food provide a reference service for scombrotoxin, ciguatera, DSP, PSP and red whelk poisoning in the UK.

Cross-Cultural Comparison↗