en - انگل شناسی Parasitology پژوهشي Research - <div style="text-align: justify;"><strong>Background and Aims</strong>: Leishmaniasis is an intracellular protozoan- parasitic disease, the common vector of transmission. Both zoonotic and anthroponotic cutaneous leishmaniasis (CL) are endemic in different foci. With regard to the cutaneous form, 1.0-1.5 million cases were reported annually with 90% of the cases. Although antimony-containing compounds that are the main drugs used to treat Leishmaniasis has been recommended for CL treatment by the World Health Organization, but there are some restrictions in this case, including high expense, side effects, frequent injections need, and incomplete efficacy. The current research was conducted the effect of <em>Staphylococcus aureus </em>and <em>Streptococcus beta-haemolytic </em>Supernatants&rsquo; on <em>Leishmania major </em>promastigotes (PMs) viability: an <em>in vitro</em> study.<br> <strong>Materials and Methods</strong>: <em>Staphylococcus aureus</em> and <em>Streptococcus beta-haemolytic</em> cultured for preparing supernatant, then <em>Leishmania (L) major</em> strain [MRHO/IR/75/ER] PMs cultured in Novy-Nicolle-Mac Neal (NNN) and roswell park memorial institute 1640 media. The cell proliferation of enzyme-linked immunosorbent assay, BrdU (Chemiluminescent) was performed as described by Roche Diagnostics. The mean of the viability PMs of <em>Leishmania (L) major</em> strain [MRHO/IR/75/ER] in culture according to <em>Staphylococcus aureus</em> and <em>Streptococcus beta-haemolytic</em> supernatant, Glocantime concentrations and in the control group (Glocantime) was obtained.<br> <strong>Results</strong>: It was shown that there was a statistical significant difference among <em>Staphylococcus aureus</em> and <em>Streptococcus beta-haemolytic</em> supernatant inhibits growth of <em>Leishmania (L) major</em> strain [MRHO/IR/75/ER] PMs with the control group (p<0.05) .<br> <strong>Conclusions</strong>: These exciting results suggest that <em>Staphylococcus aureus</em> and <em>Streptococcus beta-haemolytic</em> Supernatants have significant therapeutic potential as novel anti-leishmanial.</div> Staphylococcus aureus, Beta-haemolytic Streptococcus, Leishmania major Promastigotes, supernatant. Beta-haemolytic Streptococcus, Leishmania major , Staphylococcus aureus, Supernatant 211 218 http://ijml.ssu.ac.ir/browse.php?a_code=A-10-31-3&slc_lang=en&sid=1 Ali Fattahi Bafghi علی فتاحی بافقی No Department of Parasitology and Mycology, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Banafsheh Goudiani بنفشه گودیانی Yes Department of Pharmacy, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Mohammad Hossein Mosadegh محمد حسین مصدق afbafghi@ssu.ac.ir No School of Pharmacy, Shahid Sadoughi University of Medical Sciences, Shohadaye Gomnam Blvd, Safaeeyeh, Yazd, Iran School of Pharmacy, Shahid Sadoughi University of Medical Sciences, Shohadaye Gomnam Blvd, Safaeeyeh, Yazd, Iran Arefeh Dehghani عارفه دهقانی afbafghi@ssu.ac.ir No School of Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. School of Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Maryam Sadeh مریم ساده No Department of Laboratory Technology, Faculty of Paramedicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.