martes, 16 de agosto de 2011
Breakthrough natural preservative kills foodborne bacteria - research
A new naturally-occurring preservative that could be added to food during processing has the potential to kill deadly pathogens and extend shelf life.
Researchers from the University of Minnesota said they have found a novel lantibiotic - a peptide produced by a harmless bacterium - that is the first natural preservative with the ability to kill gram negative bacteria, such as E. coli, Salmonella and L. monocytogenes.
Lantibiotics currently available to industry only combat gram positive bacteria and are ineffective against gram negative varieties, they said.
Gram negative bacteria such as E. coli and Salmonella, account for more than half of food recalls in the US that cost food producers an estimated $1.4bn in 2010. Some 28% of the annual 3,000 deaths from foodborne illnesses are linked to Salmonella, according to the CDC.
The lantibiotic strain, called Bisin, was uncovered by chance and developed from a culture of Bifodobacterium longum, commonly found in the human intestine.
Dan O’Sullivan, professor of food science and nutrition in the university's College of Food, Agricultural and Natural Resource Sciences, said the strain could be used to prevent harmful bacteria in meats, processed cheeses, egg and dairy products, canned foods, seafood, salad dressing, fermented beverages and many other foods.
A further advantage is that lantibiotics are easily digestible, non-toxic, non-allergenic and are difficult for bacteria to develop resistance against, said the scientists.
Research is currently underway to determine optimal growth conditions and the precise ability of the preservative to inhibit microbial activity.
The lantibiotic falls within the GRAS (generally recognised as safe) category. However, if its potential as a naturally occurring antibiotic were developed it would require approval from the FDA.