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Alkaloids are employed throughout multiple kingdoms, with one of the most well-known applications being defense. However, social organisms like ants have evolved a broader array of usages for these compounds, such as communication, resource monopolization, and as hygienic agents against microbial pathogens. Megalomyrmex, a small neo-tropical ant genus, produce a diversity of alkaloids for a variety of applications to aid them in defense and parasitism, yet the use of these substances as antimicrobials have not yet been documented in this group. For this study, we tested for the presence of trans-2-butyl-5-heptylpyrrolidine, a venom-derived alkaloid found in multiple ant genera and in or on the workers and brood of Megalomyrmex c.f. wallacei. We assessed the antimicrobial properties of this alkaloid using six diverse bacterial species and determined the minimum inhibitory concentration of the alkaloid for each using broth microdilution in a 96-well microtiter plate. This alkaloid inhibits the bacterial growth of six species (three Gram-positive and three Gram-negative strains). We also determined that trans-2-butyl-5-heptylpyrrolidine was the only alkaloid found in the venom of this ant species, and it can be detected on brood, suggesting possible transmission between workers and offspring. These findings suggests that Megalomyrmex c.f. wallacei may transfer the alkaloid-containing venom onto the brood to combat microbial pathogens, as has been shown in other ant species.