화학공학소재연구정보센터
Renewable Energy, Vol.141, 782-790, 2019
Isolation and characterization of new Botryococcus braunii (Trebouxiophyceae) isolates
Four isolates of Botryococcus braunii Kutzing were isolated from the Nile River in Egypt. The morphological examinations and results of 5.8S rRNA gene sequences confirmed that EG-Bb01 (JN580448.1), EG-Bb02 (JN580449.1), EG-Bb03 (JN580450.1) and EG-Bb04 (JN580451.1) are B. braunii. The isolates were cultivated in modified Chu 13 medium and incubated for 8 weeks at 25 +/- 1 degrees C under light intensity of 16 +/- 3 mu mol m(-)(2)s(-1) with 16:8 h light: dark cycle. The dry weight biomass ranged between 0.382 gl(-1) and 0.628 gl(-1) for the isolates EG-Bb03 and EG-Bb01. Also, the hydrocarbon production (% w/w) varied significantly (P <= 0.05) between 33% (EG-Bb03) and 53% (EG-Bb01). GC/MS analysis revealed marked qualitative and quantitative variations in hydrocarbon profile of B. braunii isolates. A total of 24 C-16-C-31 different compounds were identified. The hydrocarbon of the four isolates was mainly composed of aliphatic hydrocarbons with the odd carbon numbered C-25-C-31, indicating that these isolates are a typical race A of B. braunii. Isolate EG-Bb01 maintained the highest content of C-25-C-31 hydrocarbons of (36.44%). The hexahydrofarnesylacetone (C18H38O) ketone was detected in the four isolates with different proportions ranged between 0.216% (EG-Bb01) and 13.86% (EG-Bb04). Meanwhile, the alcohol hexacosanol C26H54O (31.52%) was only detected in the isolate EG-Bb03. (C) 2019 Elsevier Ltd. All rights reserved.