Study on antibacterial activities of six types of tea against some pathogenic entero bacteria

To evaluate the antibacterial activities of six types of tea and investigate the possibility of drinking tea to prevent intestinal diseases. Double dilution method and the Oxford Cup were used to study the antibacterial activities of green tea, black tea, oolong tea, yellow tea, white tea and black tea on pathogenic entero becteria Escherichia coli and Staphylococcus aureus. Results:The soaking extract of all of 6 types of tea could inhibit Staphylococcus aureus at the concentration of 24mg/mL and could inhibit Escherichia coli at the concentration of 48mg/mL, and the higher the concentration of tea soaking extract, the stronger the antibacterial activity were. The soaking extract of green tea, oolong tea, yellow tea, white tea below drinking concentration (6mg/mL) could still inhibit Staphylococcus aureus. In the 6 types of tea, the green tea showed strongest antibacterial activity and that of black tea was the weakest and yellow tea and white tea was stronger than dark tea and black tea. The above results suggested that all of 6 types of tea had antibacterial activities against pathogenic entero bacteria, which might be relevant with tea chemical content.