Featured Research

from universities, journals, and other organizations

E. coli, Salmonella may lurk in unwashable places in produce

Date:
August 15, 2011
Source:
Purdue University
Summary:
Sanitizing the outside of produce may not be enough to remove harmful food pathogens, according to a new study that demonstrated that Salmonella and E. coli can live inside plant tissues.

Amanda Deering and Robert Pruitt found that foodborne pathogens can live inside plant tissues.
Credit: Purdue Agricultural Communication photo/Tom Campbell

Sanitizing the outside of produce may not be enough to remove harmful food pathogens, according to a Purdue University study that demonstrated that Salmonella and E. coli can live inside plant tissues.

Related Articles


E. coli 0157:H7 was present in tissues of mung bean sprouts and Salmonella in peanut seedlings after the plants' seeds were contaminated with the pathogens prior to planting. Amanda Deering, a postdoctoral researcher in food science, said seeds could be contaminated in such a manner before or after planting through tainted soil or water.

"The pathogens were in every major tissue, including the tissue that transports nutrients in plants," said Deering, whose results were published in separate papers in the Journal of Food Protection and Food Research International.

Deering and Robert Pruitt, a professor of botany and plant pathology, said finding pathogens inside plants has been challenging because tests require slicing off pieces of the plants, which can move the bacteria from the outside to the inside or vice versa. It becomes difficult to know where a pathogen might have been before the plant was cut.

"The results are often imprecise because the methods allow bacteria to move," said Pruitt, a co-author of the findings.

Deering used a fixative to freeze the location of the bacteria in the plant tissues before slicing samples. Antibodies labeled with fluorescent dye were used to detect the pathogens, a process called immunocytochemistry.

"This shows us as close to what was in the plant when it was living as possible," Deering said. "The number of bacteria increased and persisted at a high level for at least 12 days, the length of the studies."

Deering said she was able to count hundreds of bacteria in almost every type of tissue.

Proper sanitization would eliminate Salmonella and E. coli from the surface of foods, but not inner tissues, Deering and Pruitt said. Cooking those foods to temperatures known to kill the pathogens would eliminate them from inner tissues.

Deering and Pruitt will continue to study the pathogens to determine how they survive inside plant tissues and possible ways to eliminate them. The U.S. Department of Agriculture's Agricultural Research Service funded their work.


Story Source:

The above story is based on materials provided by Purdue University. Note: Materials may be edited for content and length.


Journal References:

  1. Amanda J. Deering, Robert E. Pruitt, Lisa J. Mauer, Bradley L. Reuhs. Identification of the Cellular Location of Internalized Escherichia coli O157:H7 in Mung Bean, Vigna radiata, by Immunocytochemical Techniques. Journal of Food Protection, 2011; 74 (8): 1224 DOI: 10.4315/0362-028X.JFP-11-015
  2. Amanda J. Deering, Lisa J. Mauer, Robert E. Pruitt. Internalization of E. coli O157:H7 and Salmonella spp. in plants: A review. Food Research International, 2011; DOI: 10.1016/j.foodres.2011.06.058

Cite This Page:

Purdue University. "E. coli, Salmonella may lurk in unwashable places in produce." ScienceDaily. ScienceDaily, 15 August 2011. <www.sciencedaily.com/releases/2011/08/110815152049.htm>.
Purdue University. (2011, August 15). E. coli, Salmonella may lurk in unwashable places in produce. ScienceDaily. Retrieved December 21, 2014 from www.sciencedaily.com/releases/2011/08/110815152049.htm
Purdue University. "E. coli, Salmonella may lurk in unwashable places in produce." ScienceDaily. www.sciencedaily.com/releases/2011/08/110815152049.htm (accessed December 21, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Sunday, December 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Reuters - Innovations Video Online (Dec. 21, 2014) A team of scientists led by Danish chemist Jorn Christensen says they have isolated two chemical compounds within an existing antipsychotic medication that could be used to help a range of failing antibiotics work against killer bacterial infections, such as Tuberculosis. Jim Drury went to meet him. Video provided by Reuters
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Reuters - Light News Video Online (Dec. 19, 2014) Millions of monarch butterflies begin to descend onto Mexico as part of their annual migration south. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins