## 4 Discussion  
We determined the bactericidal activity of the _B. karatas_ fruits' methanolic extract (ME) against _E. coli_, _S. enteritidis_, _S. flexneri_, and _E. faecalis_ (causal agents of human infections) [5, 20]; it was shown that these results are consistent with those reported in _Bromelia pinguin_[6]. We found that the bactericidal activity resisted the sterilization temperature, meaning its potential benefits are still maintained when the fruits are consumed cooked since cooking is necessary to avoid oral injuries caused by their proteolytic activity [11]. In another study, it was determined that the protein extract of the fruits had bactericidal activity, but this was not resistant to heat [14, 15], which differs from the heat-resistant bactericidal activity of the methanolic extract found in the present study. The decrease of 45% in bactericidal activity after the treatment with activated charcoal can be explained by the ability of activated charcoal to remove compounds by adsorption, and the removal effectiveness is influenced by the molecular size, polarity, and branching of the molecule. For example, branched aromatic compounds are more effectively adsorbed on activated charcoal than linear and small molecules such as ethanol and methanol [21, 22]. \begin{table}
\begin{tabular}{c c c c c} \hline
**No.** & **Compound Name** & **Area \%** & **No.** & **Compound Name** & **Area \%** \\ \hline
13 & 2,5-Parandione, 3,4-dimethyl & 0.22 & *38 & Ethyl propionylacetate & 1.22 \\ \hline
*14 & Pent-2-ynal & 0.29 & *39 & Methyl 3-hydroxypentanoate & 1.12 \\ \hline
*15 & 1,2-Butadiene & 0.64 & *40 & 3-Methyl-hexane-1,6-diol & 0.77 \\ \hline
16 & Hexan-3-yl acetate & 1.41 & *41 & Heptyl butyrate & 2.14 \\ \hline
*17 & Pentanoic acid, 4-oxo & 1.45 & *42 & Triethylene glycol monododecyl ether & 1.21 \\ \hline
*18 & 1,5-Diacetoxypentane & 1.23 & *43 & Malic Acid & 1.49 \\ \hline
*19 & 2-Propanamine, N-methyl-N-nitroso & 1.72 & *44 & 2-Ethyl-3-hydroxyhexyl 2-methylpropanoate & 1.37 \\ \hline
*20 & Methylfuran-3-carboxylate & 1.08 & *45 & 2,3,5,6-Tetrafluoranisole & 0.60 \\ \hline
21 & Furyl hydroxymethyl ketone & 1.26 & *46 & Ethanone, 1-(2,5-dimethoxyphenyl) & 0.60 \\ \hline
22 & Methyl 2-fluoroate & 1.69 & *47 & 1,2,4-Cyclopentanetrieting, 3-(2-pentenyl) & 0.40 \\ \hline
23 & Cyclopentene & 1.11 & *48 & m-Ethyl aminophenol & 0.25 \\ \hline
*24 & 2-Cyclopentene-1-one, 2-methyl & 0.77 & *49 & 2,4,6 (3H)-Pteridinetrione, 1,5-dihydro & 0.39 \\ \hline
*25 & 3H-Pyrazol-3-one, 2,4–dihydroxy-2,4,5-trimethyl & 2.55 & & \\ \hline \end{tabular} Note: Items with an asterisk were removed with activated charcoal treatment and aromatic compounds are underlined.  
\end{table} 
Table 2: _Cont._  
Figure 2: HPLC quantification of common compounds in the methanol extract (ME), the methanolic extract treated with activated charcoal (MEC), the ethyl acetate fraction (EAF), and the methanol fraction (MF). In the GC-MS analysis, 37 of the 49 compounds detected in the ME before charcoal treatment were removed, including 9 aromatic compounds. It was also possible to detect 26 compounds that were not detected in the ME; in this sense, activated charcoal is also likely to remove substances that were not detected in ME. The recovery of these removed compounds can be considered a method to isolate part of the antibacterial substances from _B. Karatas_ fruits. However, the bactericidal activity of the substances removed still needs to be identified and evaluated. On the other hand, the detection of new compounds in the MEC could have been because its concentration increased or the substances that prevented their detection, before treatment, were removed. In the same way, compounds were detected in the ethyl acetate and methanolic fractions that were not detected in the methanolic extract; this could be due to the compound enrichment and the removal of substances that interfere in the detection process [23].