Antibacterial activity of aqueous and ethanolic extracts of Portulaca oleracea L. and Taraxacum mongolicum Hand.-Mazz against pathogenic bacteria of cow mastitis

摘要

As the problems of bacterial resistance and safety of dairy products have become more prominent, alternative medicine for antibiotics in treating cow mastitis is needed. In the present study, antibacterial activity of aqueous and ethanolic extracts of Portulaca oleracea L. and Taraxacum mongolicum Hand.-Mazz against the main pathogenic bacteria (Escherichia coli, Staphylococcus aureus, Streptococcus agalactiae and Streptococcus dysgalactiae) of cow mastitis was evaluated using disc diffusion method. The results showed that aqueous and ethanolic extracts of the two herbs both could inhibit the four pathogenic bacteria of cow mastitis at different level. All extracts of the two herbs displayed the highest antibacterial activities against Escherichia coli than other bacteria. For Portulaca oleracea L., ethanolic extracts had higher antibacterial activities than aqueous extracts except for against Escherichia coli. However, for Taraxacum mongolicum Hand.-Mazz, ethanolic extracts had lower antibacterial activities than aqueous extracts. These results indicate that extracts of Portulaca oleracea L. and Taraxacum mongolicum Hand.-Mazz have the potential to be used in treating cow mastitis.