Antibacterial activity and in vitro anti-tumor activity of the extract of the larvae of the housefly (Musca domestica)

One of the significant characteristics of traditional Chinese medicine is the use of insects, other terrestrial arthropods and their products as drugs. In the present work, the extract of housefly (Musca domestica) larvae was studied by an agar well diffusion assay and minimum bactericidal concentration (MBC) determination for detection of antimicrobial activity and by MTT assay method to test its in vitro anti-tumor activity. In our studies, the extract inhibited six tested bacterial pathogens and Escherichia coli Jm109, a gene-modified strain resistant to ampicillin with the MBCs ranging from 200 to 1600 mu g/ml, while Gram-positive bacteria were more sensitive than Gram-negative bacteria. The extract showed high in vitro anti-tumor activity against human colon cancer cell line CT26 with the IRs ranging from 62 to 89%. The extract of housefly larvae inoculated with Shigella dysenteriae 51302 exhibited higher antibacterial activity and in vitro anti-tumor activity than that of native larvae, which may indicate the same principle involved in the use of Bombyx mori larvae infected with silk moth fungus Beauveria bassiana and Hepialis larvae infected with Cordiceps fungus in the traditional Chinese medicine. Both extracts did not show any coagulation activity and haemolysis activity against rabbit erythrocytes at 500 and 1000 mu g/ml. The results support its use in the traditional Chinese medicine, and warrant the further identification of the active molecule in the housefly larvae. (c) 2006 Elsevier Ireland Ltd. All rights reserved.