Botryococcus braunii strains compared for biomass productivity, hydrocarbon and carbohydrate content

Area of Science:

• Microbiology
• Biotechnology
• Industrial Microbiology

Background:

• Botryococcus braunii is a microalga with potential for producing valuable compounds like hydrocarbons and carbohydrates.
• Standardized comparisons across different B. braunii strains are challenging due to varied cultivation conditions.
• Identifying superior strains is crucial for optimizing biopolymer and biofuel production.

Purpose of the Study:

• To compare biomass productivity, hydrocarbon content, and carbohydrate content across 16 different strains of Botryococcus braunii.
• To identify strains with high yields for industrial applications.

Main Methods:

• Cultivation and harvesting of 16 B. braunii strains from six culture collections.
• Measurement of biomass productivity (g L⁻¹ day⁻¹).
• Quantification of hydrocarbon and carbohydrate content (% dry weight) and monosaccharide composition.

Main Results:

• Biomass productivity varied, with strain AC768 achieving the highest at 1.8 g L⁻¹ day⁻¹.
• Hydrocarbon content ranged from negligible to 42% dry weight, with 'Showa' and 'AC761' exhibiting the highest yields.
• Carbohydrate content ranged from 20% to 76% dry weight, with CCALA777 being the top producer. Glucose and galactose were predominant monosaccharides, with notable fucose levels in CCALA778.

Conclusions:

• Significant variation exists among B. braunii strains regarding biomass, hydrocarbon, and carbohydrate production.
• Specific strains like AC768, 'Showa', AC761, and CCALA777 demonstrate high potential for industrial applications.
• Further research into optimizing cultivation for these high-yielding strains is warranted.