The Effect of Tea Infusions on the Proliferation of Selected Bacteria Important for the Human Intestinal Tract

Tea infusions are consumed frequently and in large amounts, so they may play a role in modelling intestinal microflora or in preventing bacterial diseases. The present study examined the effect of different kinds of tea (black, green and pu-erh) on Lactobacillus rhamnosus, Lactobacillus plantarum, Leuconostoc mesenteroides subsp. mesenteroides, Escherichia coli, Staphylococcus aureus and Salmonella enteritidis. In order to ascertain the connection between antioxidant and antimicrobial properties, the content of polyphenolic compounds and the reducing power of the teas were assessed. The rate of bacterial proliferation was measured by calculating the generation time between the 2nd and 6th hour of incubation. Staphylococcus aureus was the most sensitive to the addition of tea extracts to the media. Among lactobacilli (LAB), Lactobacillus casei proved to be sensitive mainly to the extracts of black and pu-erh tea. The value for reducing power does not fully correspond to the content of polyphenols and antimicrobial properties.