Carbohydrate obtained from cheese whey boosts immunity to disease

Researchers at UC Davis have extracted oligosaccharides similar to those found in mother's milk from whey permeate, a dairy industry waste.

By Elton Alisson

Agência FAPESP – Human breast milk contains carbohydrates called oligosaccharides that serve as food for “good bacteria” such as Bifidobacterium infantis.

According to Daniela Barile, a professor in the Department of Food Science & Technology at the University of California, Davis, in the United States, when these beneficial bacteria proliferate and colonize the gut, they boost the host organism’s immunity. In the case of humans, they help protect babies from infections and diseases caused by harmful gut microbes such as Escherichia coli.

“There’s evidence to show that mother’s milk promotes intestinal health in babies, enhancing their immunity and protecting them from a wide range of health issues, such as obesity, diabetes, liver problems and cardiovascular disease,” Barile said.

Barile leads a group of researchers at UC Davis who have obtained oligosaccharides similar to those found in breast milk from whey permeate. Also called milk serum or milk permeate, whey permeate is obtained by partial removal of protein from whey, the liquid remaining after milk has been curdled and strained for the purposes of cheesemaking.

The researchers’ idea is to add these oligosaccharides to food supplements as a way of restoring microbial balance in the digestive tract. Such treatments could soon be used to boost the defenses of people with compromised immune systems, such as patients with HIV or undergoing chemotherapy, the elderly, and non-breastfeeding babies.

Barile presented findings from the research in her presentation to a session on food and agriculture during FAPESP Week UC Davis in Brazil, held in São Paulo on May 12-13.

“The discovery of oligosaccharides in whey permeate opens up new opportunities to use these alternative molecules, which mimic as closely as possible the structural and functional characteristics of human milk oligosaccharides, in supplements and dairy products with the aim of reducing microbial imbalances in the infant and adult intestine,” Barile said.

Cows produce oligosaccharides that are structurally similar to those found in mother’s milk, although the amounts produced decrease after the first few days of lactation.

Because oligosaccharides are hard to synthesize chemically for large-scale use, Barile’s group are looking for alternative sources. Hence their development of techniques to obtain them from whey permeate.

“Whey is the waste product of cheesemaking and is produced in enormous amounts. It’s not environmentally friendly and it’s hard to dispose of. Dairy firms can’t just throw it away in water courses or drains,” Barile said.

She explained that 100 liters of milk are required to produce ten kilograms of cheese, with 90 liters of whey left over. This whey contains about 50% of the nutrients in milk. Some 200 million metric tons of whey are produced worldwide each year, 3 million of them in Brazil.

Whey-derived products currently available from retailers include whey protein isolate or concentrate, obtained by recovering the proteins in waste from cheesemaking via ultrafiltration.

“Besides these highly profitable products, we can obtain whey permeate, which has a high lactose content and is a pollutant that costs a great deal to eliminate,” Barile said.

“Implementation of a low-cost process to recover oligosaccharides systematically from whey permeate would enable the dairy industry to add value to this byproduct and create dairy products with a high market value.”
 

Clinical validation

The researchers at UC Davis are studying the development of processes that combine biotechnology and industrial engineering to enable the dairy industry to extract large quantities of oligosaccharides from whey permeate.

In parallel, other groups of researchers at the same institution are conducting in vitro studies with epithelial cells, as well as trials in animal models and humans, to evaluate the prebiotic and immunomodulatory effects of the oligosaccharides obtained in the laboratory from whey permeate.

In a project supported by the Bill & Melinda Gates Foundation, a group of researchers at UC Davis are also studying how gut bacteria consume oligosaccharides.

The results of the study could contribute to the development of substances that boost the immunity of non-breastfed children.

“Mother’s milk plays an important role in initial microbial colonization of the intestine,” Barile said. “Babies fed only breast milk present with lower levels of potentially pathogenic gut microbiota, such as enterococci, enterobacteria, clostridia and bacteroides. Children fed on artificial infant formula present with a larger number of these bacteria.”

Besides Barile, other speakers at the session on food and agriculture included Bernadette Dora Gombossy de Melo Franco, Full Professor at the University of São Paulo’s School of Pharmaceutical Sciences (FCF-USP) and director of the Food Research Center (FoRC), one of the Research, Innovation and Dissemination Centers (RIDCs) funded by FAPESP; Bennie Osburn, Director of Outreach and Training at UC Davis and Dean Emeritus of the School of Veterinary Medicine; and Luiz Antonio Martinelli, a professor at the University of São Paulo’s Center for Nuclear Energy in Agriculture (CENA-USP).