Detection of bleomycin- like antitumor agent produced by Streptomyces spp. local isolates تشخیص المضاد (بلومایسین) الشبیه المنتج بواسطة عزلات محلیة لبکتریا Streptomyces spp.

Ethyl acetate extracts of fermentation cultures of five local streptomyces isolates sry-3, sry-25, 5b, 10, ns-38 were identified as inhibitors of plasmacytoma cell line. concentration at 0.016 μg/ml of ethyl acetate extract of (sry-3,sry- 25,5b,10,ns-38) inhibited (46%,40%,21%,34%,34%) of mouse plasmacytoma cells respectively, where as 0.5 μg/ml inhibited (58%, 55%, 35%, 33%, 36%) of plasmacytoma cells . quantities analysis of crude extracts by using hplc on the basis of their retention times showed that the values were (4.3,4.4,4.86,4.83&4.84) min. for sry-3, sry-25, 5b, 10,ns-38 respectively, while the retention time of standard antitumor compounds was (4.26) min. this suggests that unknown compound of sry-3 extract contain bleomycin-like compound. addition of standard bleomycin to crude extract of sry-3 increased milliabsorbans unit (m.a.u.) from 0.49 to 1.4. the concentration of bleomycin-like antitumor in fermentation broth of sry-3 isolate was 3.441 μg/ml. the five streptomyces isolates have moderate activity against gram-positive and gram-negative bacteria, while standard blm have no activity.