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ANALES 4. DISCUSSION
RANF The concentrations under study proved to be highly effec-
www.analesranf.com tive, blocking some pathway for the growth of enterobacteriaceae,
and showing that the vehicle does not affect growth, however it is
2.2 Preparation of strains under study and evaluation of unknown if it affects bacterial-bacterial cellular communication.
the hexanic extract of Tagetes lucida From 75 µl there is almost total inhibition, and with 100 µl there
is total inhibition of bacterial growth.
Wild-type strain cultures obtained from stool cultures of
patients from the Ixtlahuaca Valentín Gómez Farías General Hospital The study previously carried out by Céspedes et al, in which
donated and provided by the microbiology department of the Uni- they evaluated the activity of different molecules obtained from the
versity of Ixtlahuaca CUI who used the strains in their reservoir were Tagentes lucida plant on Gram positive and Gram negative bacteria,
used. inspired its replication of the present work, modified in several as-
pects as follows.
Inoculation of tubes with 3 ml of BHI broth with a 0.5
McFarland scale of the enterobacteria was performed. In the case of Firstly, the solvent used to macerate Tagetes lucida used
Petri dishes, a routine sowing of Kirby Bauer was performed. by Céspedes was methanol, then the separation, identification and
purification of different coumarins and flavonoids were carried out,
The tubes with BHI broth inoculated with Shigella, two se- which were individually evaluated as growth inhibitors of the bac-
ries were performed in triplicate, in the first series 100 µl, 200 µl teria under study. In the study carried out in our research group, Ta-
and 300 µl of vehicle (Hexane) were added. While the second series getes lucida obtained and collected in Tenancingo de Degollado,
of tubes with BHI broth and Shigella, different concentrations of the State of Mexico, was used, while the one studied by Céspedes was
hexanic extract were added, 25µl, 50 µl, 75 µl, 100 µl, 150 µl, 200 collected in the State of Michoacan, which influences the type and
µl, 250 µl, 300 µl. Both series of tubes were incubated for 18h at quantity of secondary metabolites expressed by the plant.
37 ° C.
A further change in the replication of the study is the sol-
The tubes with BHI broth inoculated with Salmonella, two vent used, while Céspedes used methanol, a polar solvent, in our
series were performed in triplicate, in the first series 100 µl, 200 µl study hexane, a non-polar solvent, was used. Therefore, the diffe-
and 300 µl of vehicle (Hexane) were added. While the second series rence in secondary metabolites can vary even more, not only due to
of tubes with BHI broth with Salmonella, different concentrations of the geographical difference in the collection of the plant, but also
the hexanic extract were added, 25µl, 50 µl, 75 µl, 100 µl, 150 µl, the type of metabolites obtained by the solvent used. On the other
200 µl, 250 µl, 300 µl. Both series of tubes were incubated for 18h hand, Céspedes purified each of the metabolites found in the mash,
at 37 ° C. while we used the mash with all the metabolites that could be ob-
tained from the process. A control experiment was made in triplicate
For the determination on the inhibition of the enterobac- with hexane as well as a petri dish, to verify that the solvent did not
teria under study, in petri dish, sowing was carried out by the method affect bacterial growth and that the effect that occurred was mainly
of Kirby Bauer. Subsequently to the crops were added different con- due to the action of Tagetes lucida.
centration of the vehicle (hexane) and another series of the mace-
rated. This was done with each of the enterobacteria in triplicate.
Each of the trials and series were performed in triplicate, both for
Salmonella and Shigella. The boxes were incubated for 18h at 37 °
C.
3. RESULTS
Table 1. This table shows the inhibition achieved in the growth of Shigella and Salmonella, both with vehicle and with extract. Where ++++ represents
representative growth, +++ partial inhibition and - total inhibition of bacterial growth.
Efecto del extracto hexánico de Tagetes lucida sobre la inhibi- 115
ción del crecimiento de enterobacterias Shigella flexneri y
Salmonella typhi
Jorge Angel Almeida-Villegas; Rodolfo Garcia-Contreras; et al.
An Real Acad Farm Vol. 86. Nº 2 (2020) · pp. 113 -116
