氯酸钠生产过程的环境控制.pdf

Effect of sodium chlorate on almonella Typhimurium in the pig gut(NPPC#00-136
Principle Investigator: Robin C. Anderson PHD
Institution USDA/ARS, SPARC, 2881 F&B RD, College Station, TX 77845
II. Abstract: Salmonella cause disease and compromise food safety. Consequentl,
strategies are sought to reduce their concentration in pigs immediately before processing
Respiratory nitrate reductase activity possessed by Salmonella coincidentally catalyzes th
intracellular reduction of chlorate to chlorite, a consequence that kills the microbe. Since most
beneficial gut bacteria lack respiratory nitrate reductase, we conducted several studies to see if
chlorate may selectively kill Sa monella, but not beneficial microbes, within the pig gut. In the
first study, weaned pigs orally infected with Salmonella Typhimurium were treated 8 and 16 h
later via oral gavage(10 mi)with 0 or 100 MM sodium chlorate. The pigs were euthanized at 8
h intervals after receiving the last treatment and samples collected by necropsy were culture
for Salmonella. A significant chlorate treatment effect(P< 0.05)on cecal Salmonella
concentrations was observed. although a treatment x time after treatment interaction was also
observed which suggests that the chlorate effect was concentration dependent. In follow
studies, 0, 15 or 30 MM sodium chlorate solutions were administered via drinking water to
weaned or finished pigs experimentally challenged 24 h earlier with Salmonella Typhimurium
These pigs were euthanized 12 h or 24 h after being allowed ad libitum access to their
respective treatments and ut samples were again cultured for the challenge Salmonella strain
In these studies, Salmonella concentrations in gut contents collected from chlorate treated pigs
were reduced up to 1000-fold compared to concentrations from control pigs. These results
demonstrate that chlorate administration may be a practical procedure for reducing
gastrointestinal concentrations of Salmonella in pigs immediately prior to processing