Abstract:
Green and black teas extracts are known for their
antibacterial activity against many pathogenic
microorganisms. These studies have been necessitated by the need to combat the recent rise of drug-
resistant human pathogens which is becoming a common occurrence in the world making easily
manageable infections to become life threaten
ing illnesses. This study evaluated the antimicrobial
activity of water soluble green and black tea extracts from a high quality Kenyan tea clone TRFK 6/8
against antibiotic resistant
Escherichia coli
ATCC 25922 and
Staphylococcus aureus
ATCC 25923 using
agar well diffusion method. Green and black tea ext
racts effectively inhibited the growth of both
E. coli
ATCC 25922 and
S. aureus
ATCC 25923 at concentrations of 0.1 and 0.05 mg/ml, respectively after 24 h.
Green tea extracts and ge
ntamicin showed greater zone of inhi
bition compared to penicillin G. In
addition, the possible synergistic activity of water
soluble green tea extract and antibiotics was also
determined using agar well diffusion method. A co
mbination of penicillin G and green tea extract
inhibited the growth of
E. coli
ATCC 25922 and
S. aureus
ATCC 25923 compared to penicillin G alone
while gentamicin exhibited an additive and antagonist
ic effect depending on tested bacteria. Green and
black tea extracts can be used as an antimicrobial agent and also green tea extract can be used in
combination with penicillin G to manage resistan
t pathogenic bacteria. Fur
thermore, tea which is a
proven safe, cheap and readily available compound can
be used in more ambitious trials to test the
antimicrobial efficacy and chemo-preventive
effects in animal and human models.
