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6.3 DISCUSSION
The bio-autoautographic assay was carried out to dertemine the presence of
individual compounds with antibacterial activity, which would allow for further
isolation of the active compounds. The spots that are marked with the arrows are the
compounds that each plant secreats that were separated by the TLC method and the
Rf values were calculated. The results obtained showed that the compounds
responsible for the inhibition of microorganisms are more than one for each plant
which is supported by the zones of inhibition on the plates. The results showed that
the larger the variety of compounds in an extract the better the chances of inhibition,
as visible in Combretum erythrophyllum extract (Figure 6.8). The results were
interpreted as follows: the clear zones were the zones of inhibition by the plant
compound and the pink color was the INT that was sprayed on the plate to allow us
to see the growth of microorganisms that remained pink. It is recommended to
isolate these active compounds and identify them with NMR (Nuclear magnetic
resonance spectroscopy) and MS (Mass spectrometry).
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