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Reading (Medicine), European food research and technology
European Journal of Clinical Microbiology and Infectious Disease
Microbiology, Obviously my own:-), Exploring mysteries
Article: Effect of black tea (Camellia sinensis) on virulence traits of clinical isolates of Shigella dysenteriae and Escherichia coli EPEC P2 1265 strain[show abstract] [hide abstract]
ABSTRACT: The crude tea polyphenols of regular black tea were investigated in vitro for effect on virulence traits of Shigella dysenteriae and Enteropathogenic Escherichia coli (EPEC P2 1265) strains. Results showed that crude tea polyphenols of black tea significantly increased (p < 0.05) phagocytic uptake of tea-adapted S. dysenteriae cells in 30 min by 37.68% and phagocytic killing by ten-folds in 3 h. Further, acid tolerance response in EPEC P2 1265 strain was also decreased in tea-adapted culture in order: Acid adapted, tea un-adapted > acid un-adapted, tea un-adapted > acid adapted, tea adapted > acid un-adapted, tea-adapted. These results inferred that polyphenolic treatment of bacterial culture disrupts pH hemostasis which caused complete bacterial killing in 120 min when compared to tea-untreated culture where complete killing required 180 min. Serum bactericidal activity was also increased in tea-treated culture of EPEC P2 1265 when 2-h serum treatment caused complete bacterial killing but un-treated cells were killed after 3 h. Also, significant increase (p < 0.05) in enterochelin production was observed when EPEC P2 1265 was grown in presence of tea. The present findings indicate that boiling water black tea extract reduces expression of virulence traits by S. dysenteriae and E. coli EPEC P2 1265 enteropathogen as shown by decreased bacterial survival strategies. The results promote the use of tea extract against multidrug resistant Mycobacterium tuberculosae (MDR-TB) strains and other enteropathogens.European Food Research and Technology. 01/2010; 231:763-770.