Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanoparticle gives antimicrobial ability to fight Listeria longer

08.12.2010
A Purdue University research team developed a nanoparticle that can hold and release an antimicrobial agent as needed for extending the shelf life of foods susceptible to Listeria monocytogenes.

Yuan Yao, an assistant professor of food science, altered the surface of a carbohydrate found in sweet corn called phytoglycogen, which led to the creation of several forms of a nanoparticle that could attract and stabilize nisin, a food-based antimicrobial peptide.

The nanoparticle can then preserve nisin for up to three weeks, combating Listeria, a potentially lethal foodborne pathogen found in meats, dairy and vegetables that is especially troublesome for pregnant women, infants, older people and others with weakened immune systems.

Controlling Listeria at deli counters, for example, is especially problematic because meat is continually being opened, cut and stored, giving Listeria many chances to contaminate the food. Nisin alone is only effective at inhibiting Listeria for a short period - possibly only a few days - in many foods.

"People have been using nisin for a number of years, but the problem has been that it is depleted quickly in a food system," said Arun Bhunia, a Purdue professor of food science who co-authored a paper with Yao on the findings in the early online version of the Journal of Controlled Release. "This nanoparticle is an improved way to deliver the antimicrobial properties of nisin for extended use."

Yao used two strategies to attract nisin to the phytoglycogen nanopoarticles. First, he was able to negatively charge the surface of the nanoparticle and use electrostatic activity to attract the positively charged nisin molecules. Second, he created a partially hydrophobic condition on the surface of the nanoparticle, causing it to interact with partially hydrophobic nisin molecules. When the particles are hydrophobic, or repel water, they become attracted to each other.

"Both strategies may work together to allow nanoparticles to attract and stabilize nisin," Yao said, "This could substantially reduce the depletion of nisin in various systems."

For practical use, Yao said a solution containing the nanoparticles and free nisin could be sprayed onto foods or included in packaging. The solution requires a balance of free nisin and nisin on the nanoparticles.

"When you reduce the amount of free nisin, it will trigger a release of more nisin from the nanoparticles to re-establish the equilibrium," Yao said. "There will be a substantial amount of nisin preserved to counteract the Listeria."

Using a model, Yao said a sufficient amount of nisin to combat Listeria could be preserved for up to 21 days.

Yao and his colleagues are working on using other food-based antimicrobial peptides and nano-constructs to combat Listeria other foodborne pathogens such as E. coli O157:H7 and salmonella. The U.S. Department of Agriculture and the National Science Foundation funded their research.

Writer: Brian Wallheimer, 765-496-2050, bwallhei@purdue.edu

Sources: Yuan Yao, 765-494-6317, yao1@purdue.edu

Arun Bhunia, 765-494-5443, bhunia@purdue.edu

Brian Wallheimer | Purdue University
Further information:
http://www.purdue.edu

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>