The dorsal skin of some amphibians especially frogs is associated with numerous glands which secrete different type of peptides that have antibacterial and in some cases antiviral activity. Skin of frogs is used to cure any inflammation or lesion and even scorch in traditional medicine in some countries. E. cyanophlyctis cyanophlyctis is a species of frog that lives in Iran and in some areas in India and Pakistan. In this study we collected E. cyanophlyctis from different provinces of Iran and cultivated at Ferdowsi University of Mashhad. We extracted and purified peptides secreted from skin of this frog using ultrafiltration and RPHPLC. In order to purify antimicrobial peptides, First, the skin was washed by 10ml buffer phosphate 50mM (pH = 6.8), then a 5 volt electricity was applied and extracted peptides was washed by 5ml distilled water. The solution was passed through membrane filters (with distinct micropore) at 25◦C, and utterance was concentrated using ultrafiltration membrane, cut off 10kD and 1kD respectively. The concentrated sample solution purified by RP-HPLC with C8 and C18 semi-preparative columns. Finally, we purified many peptides which have antimicrobial activity against both Gram positive and Gram negative. Others characterization including sequencing and chemical synthesis of peptides and MIC determination is being continued.

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