Abstract: It is not good enough to produce antibacterial peptides by genetic engineering because of much technology troubles involved and the mono-kind of peptide with narrow antimicrobial spectrum. It is very significant and valuable to isolate antibacterial peptides from abundant crude resource. Antibacterial peptides extracted from Musca larvae, which have multi-functions such as antibacterial and antitumor activities, are good natural medicine resources, but the product development research is few for the lower extracting ratio. Using natural material of dried Musca domestica larvae, by comparing the activities and characteristics of antibacterial peptides extracted by two methods such as heat-chromatography and alginic-acid-absorption, it had been proved that heat-chromatography was a quick, simple method with 0.26% peptides extracting ratio which was 5.2-fold to that of alginic-acid-absorption. The major antibacterial peptides extracted by heat-chromatography were determined having Mw 6.2－17.2 kD with TricineSDS-PAGE and pI 5.59－5.91 with IEF-PAGE. The peptides were very thermo-stable and had antibacterial activity against Gram-positive bacteria such as Bacillus subtilis. Besides maintaining the stability of bioactive peptides by removing the exotic proteases, the heat-chromatography could also extract non-peptides with antibacterial activity. This technique may be used to exploit the resource of houseflies sufficiently and develop the antibacterial products with high additional value supplying to medical treatment and health protection.

Key words: Musca domestica, antibacterial peptide, extraction technique, resource utilization, antibacterial product