A coated bacteria protect from the acids and bile salts found in the digestive tract read more at here www.spinonews.com/index.php/item/851-a-coated-bacteria-protect-from-the-acids-and-bile-salts-found-in-the-digestive-tract

The human digestive tract contains trillions of bacteria, many of which help digest food and fight off harmful bacteria.

Recent studies have shown that bacteria may influence, for better or worse, human diseases such as diabetes, heart disease, and cancer.

As scientists have learned more about these bacteria, many have raised the possibility that manipulates these populations, known collectively as the microbiome, could improve human health.

Ana Jaklenec, a research scientist at MIT's Koch Institute for Integrative Cancer Research and his colleagues developed a way to coat bacteria with polymer layers that protect them from the acids and bile salts found in the digestive tract. When the microbes reach the intestine, they attach to the intestinal lining and begin reproducing.

The team decided to try coating bacterial cells with thin layers of polysaccharides, or sugars. They chose two biodegradable polysaccharides known as Chitosan and alginate. These polysaccharides are known to be mucoadhesive, meaning that they will stick to the mucosal lining of the intestines.

In this study, researchers demonstrated their technique with a strain of bacteria known as Bacillus Coagulans. This strain is not normally found in the human gut, but helps to alleviate abdominal pain and bloating by producing lactic acid.

Researchers used a technique known as layer-by-layer encapsulation, achieved by depositing thin, alternating layers of positively and negatively charged materials.

Bacillus Coagulans have a negatively charged surface, so the researchers first applied a layer of Chitosan, which is positively charged, followed by a layer of negatively charged alginate. They applied a total of four layers.

This results in a very thin, gel-like coating that individually encapsulates each bacterial cell. In tests, researchers showed that this coating protects the cells from acid in the stomach, as well as bile salts. Once the cells reach the intestines, they settle in and begin replicating. The survival rate of coated bacteria had six times greater than that of uncoated bacteria.

 

For medicinal use, the coated bacteria could be easily packaged into a capsule or made into a dried powder that could be mixed into a drink. Researchers say, this strategy could also work with other microbes, such as yeast.