Erlenmeyer flask (250 ml) containing 50 ml of starch-nitrate liquid medium containing (g/l): soluble starch 20; NaN[O.sub.3] 2; K, HP[O.sub.2] 1; MgS[O.sub.4] x 7[H.sub.2]O 0.5 and distilled water up to 1 L were inoculated with three disks of 9 mm diameter taken from a 7-days old stock culture grown on starch nitrate
All these isolates were recovered from soil, sand and wastewater samples on starch nitrate agar at incubation temperature of 45.
Twenty different samples of soil, sand and wastewater were heat treated to isolate heat resistant microbes on starch nitrate agar samples containing antibiotic at 45C.
Ten actinomycetes isolates were obtained from heated samples on starch nitrate agar containing antibiotics.
Five culture media namely; nutrient broth, starch nitrate, oat meal, yeast-malt and saline liquid media, have been used to trace the growth profile and to describe mycelial balls appearance and antibacterial activity response.
Using starch nitrate medium, highest activities were recorded at 16.7 mm and 17mm against G-ve and G+ve, respectively (Figure 3).
50 Actinomycete isolates were isolated from heated soil, sand, wastewater, animal faces and some plant ecological wastes on Starch nitrate agar containing 15 g / mL of antibiotics (Tetracycline + Amphotericin B, w/w).
Serial dilutions were prepared and about 0.1 mL of each sample was spread on starch nitrate medium (Shirling and Gottlieb, 1966) which composed of g/L: 20 Starch, 1.0 KH2PO4, 0.5 MgSO4.7H2O, 0.01 FeSO4.7H2O, 3.0 CaCO3, 2.0 KNO3, 0.5 NaCl and 1 mL trace salt solution) and for solid medium preparation, 20 g/L agar was added.
Each flask was inoculated with 2mL (4A-106 CFU/mL) of bacterial suspension, previously grown at 37C for 2 days at 200 rpm in starch nitrate broth medium.
The serially diluted samples were spread over the starch nitrate agar medium (24).
250 mL Erlenmeyer flasks containing 50 mL of starch nitrate broth were inoculated with three disks of 9 mm diameter 7-days old Nocardiopsis culture grown on starch nitrate agar medium.
The ability of actinomycete isolate to grow at different concentrations of NaCl was tested using starch nitrate agar medium supplemented with 1-12% NaCl (32).