Hemoglobin is one of the most important molecules of the human body. Beyond its 
physiological activity, hemoglobins are able to inhibit the growth of several 
microorganisms. Since 1999, studies have reported that antimicrobial peptides 
can be produced by blood-feeding insects through hemoglobin digestion, and it 
has been reported that Triatoma infestans can generate an antimicrobial fragment 
from human fibrinopeptide. Thus T. infestans intestinal content was analyzed 
through Reverse Phase High-Performance Liquid Chromatography (RP-HPLC), the 
eluted fractions were tested against Micrococcus luteus, Escherichia coli and 
Staphylococcus aureus, and the active fractions submitted to mass spectrometry. 
The data obtained were compared to hemoglobin databases to verify the presence 
of hemoglobin-derived fragments. Ten fractions eluted from chromatography 
presented antimicrobial activity, and when analyzed through mass spectrometry 
revealed the presence of 8 murine hemoglobin α-chain fragments and 24 fragments 
from murine hemoglobin β fragments. Through the compilation of the fragments is 
possible to obtain over 67% coverage of both sequences. Part of the amino acid 
sequences corresponds to the sequences already identified on other intestinal 
contents of arthropods, and are highly conserved between the blood of other wild 
animals that are the most common intermediate hosts of Chagas' disease in Brazil 
and some of the main natural blood source for triatomines.