Improved XLT4 Agar: Small Addition of Peptone to Promote Stronger Production of Hydrogen-Sulfide by Salmonellae
Source: Journal of Food Protection®, Number 1, January 1995, pp. 7-119 , pp. 115-119(5)
Abstract:Xylose lysine tergitol4 agar (XLT4) is a highly selective plating medium used for isolating salmonellae. Studies have shown that XLT4 increases the recovery of salmonellae found infood, environmental and clinical samples. Further testing demonstrated that the addition of low concentrations of proteose peptone No.3 (pp3) to XLT4 produced blacker Salmonella colonies in shorter incubation times (increased hydrogen sulfide production), while still maintaining strong inhibition of competing bacteria. The increased black colony formation facilitates prompt recognition of the weaker hydrogen sulfide-producing Salmonella strains. Test concentrations of pp3 at 0.5, 1.2 and 1.8 g/L were added to XLT4 and compared with plain XLT4 using pure bacterial cultures. In addition, these four plating media, plus xylose lysine desoxycholate agar (XLD) were evaluated using nonspiked chicken liver and pork sausage samples. The concentration of 1.2 g/L of pp3 in XLT4 gave the best overall results. In virtually all cases, the Salmonella colonies were larger and more black than on plain XLT4 without pp3. The improved XLT4 is recommended for more reliable detection of salmonellae from food, environmental and clinical samples.
Document Type: Research Article
Affiliations: 1: U.S. Department of Agriculture, Food Safety Inspection Service, Bldg. 322, ARC-East, 10300 Baltimore Ave., Beltsville, Maryland 20705 2: Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland Campus, 8075 Greenmead Drive, College Park, Maryland 20742-3711
Publication date: 1995-01-01
- IAFP members must first sign in on the right to access full text articles of JFP First published in 1937, the Journal of Food Protection®, is a refereed monthly publication. Each issue contains scientific research and authoritative review articles reporting on a variety of topics in food science pertaining to food safety and quality. The Journal is internationally recognized as the leading publication in the field of food microbiology with a readership exceeding 11,000 scientists from 70 countries. The Journal of Food Protection® is indexed in Index Medicus, Current Contents, BIOSIS, PubMed, Medline, and many others.
Print and online subscriptions are available to Members and Institutional subscribers. Online visitors who are not IAFP Members or journal subscribers will be charged on a pay-per-view basis. Information can be obtained by calling +1 800.369.6337; +1 515.276.3344; fax: +1 515.276.8655, E-mail: firstname.lastname@example.org or Web site: www.foodprotection.org
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Information for Advertisers
- ingentaconnect is not responsible for the content or availability of external websites