US Department of Agriculture (USDA) scientists have reported a new method of developing prebiotics from certain crops, which could have the potential to help combat the incidence of salmonella and E. coli in animals slaughtered for their meat.
According to reports published this week by USDA's Agricultural Research Service (ARS), the new production method involves turning certain sugars from crops such as corn and soybeans into oligosaccharides.
Oligosaccharides, which are complex carbohydrates, are already recognized for their potential as prebiotics, which stimulate the growth of probiotic bacteria in the gut. These, in turn, are understood to promote intestinal health.
This has led to the growth of a market for foods containing prebiotics - which can be incorporated into a wider variety of end products than probiotic bacteria.
But ARS chemist Greg Cote says that besides unlocking minerals, vitamins and other nutrients from the oligosaccharides, probiotic bacteria can also make the colon less hospitable to pathogens, such as Salmonella and E coli, that can cause illness in humans.
When fed to chicks or piglets, for example, the prebiotics could bolster the growth and activity of probiotic bacteria so they would 'outcompete' Salmonella for space and nutrients, said ARS. This could have obvious benefits later on, when the animals are slaughtered for their meat.
Cote, who is in the ARS Bioproducts and Biocatalysis Research Unit at Peoria, Illinios, developed the oligosaccharides together with Scott Holt, an associate professor with Western Illinois University's Department of Biological Sciences. They envision formulating the oligosaccharides as a prebiotic product that could be administered orally.
ARS explains that their production method uses a microbial enzyme called alternansucrase to catalyze a series of biochemical reactions that convert sugars like sucrose, glucose or maltitol into different kinds of oligosaccharides.
"Depending on which were used, the resulting oligosaccharides bolstered the laboratory growth of Bifidobacterium, Lactobacillus, Bacteroides and some enterococci bacteria, but not pathogens such as Salmonella, E. coli or Clostridium perfringens," said the agency.
This week scientists from Portugal also reported a novel method for producing fibers from corn cobs capable of boosting the growth of friendly gut bacteria.
Using a technique called autohydrolysis, non-digestible oligosaccharides were released from the corn cob with prebiotic activity.
"With the present work it was shown that autohydrolysis constitutes a promising approach for the production of oligosaccharides from corn cobs capable of supporting the growth of Bifidobacterium adolescentis in comparison to commercial xylo-oligosaccharides," wrote lead author Patricia Moura in the journal LWT - Food Science and Technology.