New study identifies some of the major beneficial bacteria found in hard cheese, chestnuts help probiotic survival, while the intestinal microflora alters how the body responds to heavy metals.
Probiotics in Cheese
Cheese can be a good source of beneficial bacteria, however, there are limited studies that address bacterial strains that can be found in cheese. An Italian group decided to address this issue by collecting samples of hard cheese (Grana Padano) produced at multiple locations and than using modern techniques to determine the lactic acid bacteria found. While there were differences noted for the cheeses from various producers, the main beneficial bacteria found were Lactobacillus rhamnosus, L. casei, L. paracasei, L. delbrueckii, L. helveticus and Pediococcus acidilactici.
Chestnut-assisted Transit of Probiotics
The safe transit of probiotics from the mouth, through the acidic gastric secretions of the stomach, to the intestines is a huge concern for probiotics manufacturers. In an Italian project looking for new ways to use chestnuts, it was discovered that chestnut fiber could increase the survival of Lactobacilli through the stomach. This appeared to be related to a number of peptides (small proteins) in the chestnut extract used.
Microflora and Heavy Metal Exposure
Heavy metal exposure is linked to a number of diseases and finding ways to prevent chronic low-level exposure is essential. A French team wondered to what extent the microflora of the intestines was influencing heavy metal uptake. To answer this question, they employed so-called, “germ-free,” mice that do not have any intestinal bacteria. They found that the presence of intestinal bacteria altered the expression of genes needed to deal with heavy metal exposure.
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