Disease fighting bacteria in your food

Scientists at the Animal Nutrition & Animal Products Institute of the Agricultural Research Council (ARC) have developed innovative new methods of preventing diarrhea in children. By studying intestinal flora, they now have a good idea of what types of bacteria should be inside a healthy human. And what better way of delivering these than in your food? It is known as probiotic technology and is taking off in South Africa.

Diarrhoea in children

Diarrhoeal diseases are the leading cause of death among children under the age of five in South Africa1 accounting for approximately 40% of deaths in this group2. According to the Department of Health these figures are grossly underestimated as only between 15-30% of deaths are reported in the Western Cape. Large parts of the population (such as the former TBVC states) have also been excluded from these surveys. Globally over 3.2 million deaths are reported resulting from diarrhoea of which 80% are children below 5 years of age3.

Diarrhoea can be caused by viruses, bacteria or by a mixed infection. Rotavirus is the main causative viral agent among children and a number of bacteria (Salmonella, Shigella, Escherichia coli, etc.) have been associated with forms of gastroenteritis differing in degree and severity. If left without medical treatment, gastroenteritis leads to dehydration, which can result in death, particularly among infants and young children. Both the antibiotic treatment and rehydration are expensive and frequently require hospitalization, which further increases costs.

Prevention better than cure

Prevention of diarrhoea is less expensive than treatment is the philosophy of Dr Charles Horn and team-members at the ARC-Irene. The team's work involves the use of the main components of the natural intestinal bacterial flora. These bacteria are cultivated within the laboratory of ARC-Irene and can be introduced in sufficient numbers into the intestinal tract, to prevent the development of a number of intestinal disorders. These biotherapeutic bacteria have the ability to colonize the child's intestinal tract and physically protect the child from intestinal infections, which cause diarrhoea. These bacteria, referred to as probiotics, possess certain therapeutic properties, which are naturally antagonistic to the pathogens. .

The Gastrointestinal Microbiology group of the ARC has developed numerous probiotic products for the treatment of acute diarrhoea. Their latest research solved the problem of maintaining the viability of the probiotics at room temperature. They investigated various ways of incorporating the probiotics into foods, such as encapsulation of the bacteria into a chemical matrix or packaging materials that would protect the bacteria. But the winning method in the end was simple and inexpensive - packaging the bacteria (Lactobacillus species and Bifidobacterium longum) using the method of polyfoil enclosures.

Testing the product

The team put their product to the test, incorporating the probiotics into a food product designed for the school feeding scheme. The initial target was to have a high enough survival rate after three months, of the probiotics, at 37°C to administer 1 x 108 bacteria within a 50 g food product. All their expectations were exceeded when they were able to deliver 6.5 x 108 bacteria after 300 days exposure to 37°C. Existing baby and young children diets can thus be supplemented with these probiotic bacteria to prevent diarrhoea in children.

In the market

Teams at the CSIR are working at marketing the concept of probiotics in food to food companies in the country, while the company African dynamics  will investigate the viability of incorporating probiotics into the School Feeding Scheme. Several products are available through the companies Bioflora CC . A further range of probiotics containing prebiotics as well as intestinal bacteria are specially produced for Scientific Pharmaceuticals (Pty) Ltd. The ARC team have also developed biotherapeutics for animals. In this study three products were developed for a client containing probiotic bacteria of the species Lactobacillus & Bifidobacterium. Two of these products are already registered under Act 36 as animal feed additives i.e. Biotexion™ and Protexion™. A third product Petsflora™is registered and is aimed at supplying pets with probiotic bacteria.

Look out for probiotics on the shelves!

Dr. Charles H. Horn
Gastrointestinal Microbiology & Biotechnology
Animal Nutrition & Animal Products Institute
Agricultural Research Council, P/bag X2, Irene 0062

1) Annual reports of the Dept. of Health, 1995 & 1996
2) Central Statistical Service Report No. 03-09-01, 1993
3) WHO Report of 1996.


June 2003