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.