ANTI-BACTERIAL chemicals formed by the saliva of suckling calves could soon be added to products such as toothpastes and antiseptic creams.
The chemicals are part of the antibiotic arsenal in cow鈥檚 milk that helps protect newborn calves while their immune systems develop. This arsenal includes antibodies to specific microbes. But lipoproteins (proteins bound to fats) are also broken down by enzymes in the calf鈥檚 saliva to produce free fatty acids along with residual protein.
The antibiotic properties of fatty acids are well documented, says Mike Folan, director of Westgate Biological of Dublin. But what his team has shown, he says, is that the residual protein can bind to many bacteria and fungi, preventing them from sticking to surfaces such as cells or teeth. 鈥淚t鈥檚 crude, it鈥檚 primitive, but it works.鈥�
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Similar compounds are produced in the milk of most mammals, but it is easiest to extract them from cow鈥檚 milk. The company extracts the protein fraction from whey, a cheap waste product of cheese making, and treats it with the industrial equivalents of the enzymes from calf saliva, which are standard ingredients in the food industry.
Folan thinks that microbes are unlikely to evolve resistance to the compounds, which his company will market as ImmunoSAL. 鈥淩esistance would involve a fundamental change to the microbial cell wall,鈥� he says.
Folan says that in tests Westgate conducted, rats and calves treated with the milk extract were less likely to become infected when fed salmonella. And when human volunteers used toothpaste containing the compounds, build-up of dental plaque slowed by two-thirds. The results have yet to be published.
Westgate plans to develop products containing the milk extract such as treatments for conditions like oral or genital thrush, as well as antibacterial hair and hand lotions for health workers and hospital patients.