| Sumario: |
Resistance to antibiotics and heavy metals was determined in gram-negative
bacteria isolated from the San Cristobal ravine UNACHl stretch. For the isolation
of microorganisms was used Tioglicolato Broth. Blood Agar and Macconkey Agar
was used and the resistance test the automated system Vitek®2 was used. The
antibiotics used were cefotaxime, ampicillin, ciprofloxacin, gentamicin and
imipenem. In the test of resistance and susceptibility the system Vietk®2 was
used by means of the cards GN AST N249 for gram-negative bacilli. A totalof 41
microbialisolates from eleven different species of gram-negative bacteria of the
genera Pseudomonas, Klebsiella, Escherichia, Enterobacter, Citrobacter,
acinetobacter, Providence and Proteus were. The highest percentages of
resistant strains were with respect to cefotaxime and ampicillin. Of the microbial
isolates the species of Pseudomonas aeruginosa and Escherichia coli, showed
greater resistance to cefotaxime and ampicillin. Minimum concentrations of
heavy metals were used such as lead acetate (II). arsenic oxide (III), mercury
chloride (II), chromium (IV) oxide and cadmium chloride and the effects of these
were evaluated in MOeller Hinton agar about its growth. The microorganisms
identified showed greater resistance to arsenic and lead. The bacteria of the
genus emterpbacter showed greater resistance to arsenic and the species of
Klebsiella pneumoniae showed greater resistance to lead. The presence of
bacteria resistant to antibiotics poses a risk to humans and the environment. The
resistance of bacteria to heavy metals confirms their relationship with the
presence of antibiotic resistant microorganisms when the genes responsible for
this resistance are found in the same plasmid.
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