Abstract:
Understanding the relationships between diet, gut
microflora, and health is an increasingly important
area of research. Recent studies have demonstrated
that Kombucha tea provides variable antimicrobial
activity against pathogenic microbes. In this
study, we tested Kombucha tea for antimicrobial
activity against various Gram-positive and Gramnegative
bacteria, as well as yeast, using an agar
diffusion method. Standard zone of inhibition
assays were used to test the hypothesis that variance
in antimicrobial activity against Staphylococcus
aureus, Escherichia coli and Candida albicans may
be due to the varying levels of cations, like Ca2+,
found in different water-types (well water, artesian
water, city water, type-II water and distilled water).
Inductively Coupled Plasma-Optical Emission
Spectrometer (ICP-OES) results indicated that high
cationic (Ca2+, Mg2+, and Na+) content water (well
water) resulted in the largest zone of inhibition
against S. aureus, with a 12.3% difference when
compared to low cationic content water (type-
II water). E. coli maintained a constant zone of
inhibition regardless of water-type or batch-type,
while C. albicans showed no zones of inhibition.
Inhibition is either through a synergistic relationship
with the pH conditions, the other cations present
(Mg2+, Na+, Si, etc.) or a mix of b oth, as pH in
the range of 4.5 - 3 is not enough to inhibit the
growth of S. aureus. These results indicate that
a direct relationship exists between cationic
concentrations of water used to prepare Kombucha,
and antibacterial activity against S. aureus, due to
the improved fermentation of the tea with high
concentrations of cations. Strong antimicrobial
potential exists, particularly against S. aureus, which
may be useful in determining novel approaches to
synthesize antimicrobial drugs. Further study is needed
to assess other S. aureus strains, as well as to determine
how this relationship translates to human microbiota
interactions and their microbial metabolic profiles.
