Isolation, cultivation and maintenance of thermophilic
actinomycetes
The strain Streptomyces sp. Al-Dhabi-1 was isolated from
Tharban hot spring (52 °C) in Asir region southern west of
Saudi Arabia (19°2′20.37″N, 41°40′45.13″E). Ten grams
of dry sediments were added into 100 ml sterile distilled
water and shaken for 30 min. Streptomyces sp. Al-Dhabi-1
was isolated using micro dilution technique. The sediment
sample (0.5 ml from the dilution) was spread over onto following
media actinomycetes isolation agar (AIA) (Himedia)
and starch casein agar (SCA) (per liter: starch 10 g,
KNO3 2 g, casein 0.3 g, NaCl 2 g, K2HPO4 2 g, MgSO4
7 H2O 0.05 g, CaCO3 0.02 g, FeSO4 7 H2O 0.01 g, agar
18 g, and pH 7.2) supplemented with 0.05 % cycloheximide
to prevent the growth of fungi. The plates were incubated
at 55 °C for 3–5 days. Streptomyces sp. Al-Dhabi-1
was subcultured on AIA and SCA until pure culture was
obtained. The pure culture with 50 % (v/v) glycerol was
prepared and stored in the freezer (Uzel et al. 2011).