The aim of this study was to isolate and optimize the growth conditions of thermophilic microorganism from hot springs. The isolation was conducted by using the mineral salt basal medium supplemented with yeast extract at 500C. Totally, 33 isolates of thermophilic microorganism were isolated from hot springs at Truong Xuan (Khanh Hoa province) and Binh Chau (Ba Ria - Vung Tau province). | Isolation and optimization of the growth conditions of thermophilic microorganism hot springs Nong Lam University Ho Chi Minh City 55 Isolation and optimization of the growth conditions of thermophilic microorganism from hot springs Kha M. Tran1 Van T. T. Le1 Duy D. Ngo2 Khanh Q. Hoang2 Phong V. Nguyen3 amp Tri H. Nguyen1 1 Department of Biology Nong Lam University Ho Chi Minh City Vietnam 2 Institute of Tropical Biology Ho Chi Minh City Vietnam 3 Department of Biotechnology Nong Lam University Ho Chi Minh City Vietnam ARTICLE INFO ABSTRACT Research paper The aim of this study was to isolate and optimize the growth conditions of thermophilic microorganism from hot springs. The Received April 24 2018 isolation was conducted by using the mineral salt basal medium Revised May 30 supplemented with yeast extract at 500 C. Totally 33 isolates Accepted June 17 2018 of thermophilic microorganism were isolated from hot springs at Truong Xuan Khanh Hoa province and Binh Chau Ba Ria - Vung Tau province . The effects of temperature 45 - 800 C pH Keywords pH 6 - 9 and carbon sources malate pyruvate acetate glucose fructose or carbon dioxide on the growth of isolates were exam- ined. In addition the isolate morphology was also investigated Bacillus spp. by Gram and spore staining. The isolated thermophilic microor- Hot spring ganism showed the diversity in colony morphology and color ap- Isolation pearance. Most of them were rod shaped spore-forming and most Spore staining grew well at 500 C and pH 7. The highest growth of all isolates Thermophilic microorganism was observed under malate glucose or fructose as an organic car- bon source and unable to use carbon dioxide. Six out of 33 ther- mophilic microorganism isolates namely BM7 BS5 NS1 NS3 NS4 and NW6 grew rapidly under high temperatures from 50 - Corresponding author 550 C and their morphology characteristics showed high similarity Nguyen Huu Tri to Bacillus sp. The study evidenced the polymorphic diversity of Email .
