摘要:

Twenty kinds of ciguatoxic fishes such as grouper, moray eel, barracuda, catfish and snapper, etc. were collected from fish markets in Bangkok, Chanthaburi and Chonburi. Liver and meat were extracted with ether and the presence of ciguatoxin was checked by the mouse test. Ciguatoxin was not detected in any of the samples. On the other hand, water‐extracted fractions under acetic acidic conditions from meat, skin, intestine, liver and ovary of five kinds of puffer collected from Chanthaburi, Samut Sakorn and Trat caused mouse paralysis or death. The ovaries of the green rough‐backed blowfish and the starry blowfish, which are very popular in Thailand, contained large amounts of tetrodotoxin. The starry blowfish contained 1482.0 mouse units of tetrodotoxin per gram of ov

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1981.tb00424.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The nutritional requirements for the synthesis of a cholera toxin‐like toxin from Salmonella enteritidis serotype braenderup were examined. Toxin levels of both culture filtrates and sonicates were determined by the modified Chinese hamster ovary (CHO) floating cell assay. With few exceptions, most amino acids which contained charged polar R groups were stimulatory for Salmonella toxin synthesis. Glycerol enhanced toxin production to the largest extent; however, glucose was a poor carbon source suggesting that Salmonella toxin elaboration may be subject to catabolite repression. Biotin and Mn++were shown to increase the synthesis as well as release of this toxin. An ideal defined medium, supplemented with all the nutritional factors shown to stimulate toxin synthesis, was formulated. The amount of Salmonella toxin produced in this supplemented medium was about 82% of the total toxin elaborated when cultured in Casamino acids plus yeast extrac

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1981.tb00425.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

A DNA hybridization assay was used to detect isolates of Escherichia coli that have the genetic potential to produce toxin. This method was compared with the traditional Y‐1 mouse adrenal cell method for detecting pathogenic E. coli isolated from humans. Results showed that the DNA hybridization method has the potential to detect foodborne bacterial pathogens. The advantages and disadvantages of this genetic method are compared with those of the traditional assays for pathogenicit

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1981.tb00426.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1981.tb00427.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

A review of plasmids in Clostridium perfringens is presented. The characterization of the caseinase mediating plasmid pHB101 based upon limited DNase treatment, restriction endonuclease treatment, and agarose gel electrophoresis is described. Antibiotic profiles for the wild type strain and the cured strain were determined. The plasmid pHB101 was non self‐transferable. The curing procedure resulted in a stable morphological change from rod to coccoid or bacillary‐coccoid shape. A screening of C. perfringens strains showed the general presence of a 9.4 Mdal plasmid which may have been overlooked in the past due to chromosomal DNA masking effe

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1981.tb00428.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY