You are here:
ISOLATION AND IDENTIFICATION OF NONTUBERCULOUS MYCOBACTERIA FROM FOODS AS POSSIBLE EXPOSURE SOURCES
Citation:
Argueta, C., S. Yoder, A. E. Holtzman, T. W. Aronson, N. Glover, O. W. Berlin, G N. Stelma Jr., S. Froman, AND P. Tomasek. ISOLATION AND IDENTIFICATION OF NONTUBERCULOUS MYCOBACTERIA FROM FOODS AS POSSIBLE EXPOSURE SOURCES. JOURNAL OF FOOD PROTECTION 63(7):930-933, (2000).
Impact/Purpose:
1)Develop an improved method(s) for isolating and/or detecting nontuberculous mycobacteria from potable water. 2)Determine the best DNA fingerprinting method to use to determine genetic relatedness with clinical and environmental isolates.
Description:
A variety of foods collected from local supermarkets and produce stands were examined as possible sources of nontuberculous mycobacterial exposure. Food samples were combined with sterile ultrapure water and manually shaken. To remove large particles, the suspensions were filtered through a sterile strainer, centrifuged, and the supernatants were discarded. The food pellets were stored at -75oC. The pellets were treated with either oxalic acid or sodium hydroxide-sodium citrate solutions to reduce contamination by nonmycobacterial organisms. Decontaminated pellets were cultured on both Middlebrook 7H10C agar and Middlebrook 7H10C agar with supplemental malachite green. Plates sere observed for growth at 2 and 8 weeks. Isolates demonstrating acid-fastness were identified to species using polymerase chain reaction and restriction enzyme analyzsis. Nontuberculous mycobacteria (NTM) were recovered from 2 of 121 foods. Six different species of NTM were isolated, the most predominant being Mycobacterium avium.