Efficient brazzein production in yeast (Kluyveromyces lactis) using a chemically defined medium

Area of Science:

• Biotechnology
• Food Science
• Microbial Fermentation

Background:

• Brazzein is a sweet-tasting protein with functional properties like antioxidant and anti-inflammatory effects.
• Efficient and cost-effective production of recombinant brazzein is crucial for its industrial application.

Purpose of the Study:

• To optimize a chemically defined medium for high-yield secretory production of recombinant brazzein in Kluyveromyces lactis.
• To evaluate the purity, yield, and cost-effectiveness of brazzein production using the optimized defined medium.

Main Methods:

• Investigated and optimized media compositions for two fermentation phases: cell growth and brazzein production.
• Utilized Kluyveromyces lactis as the expression host for secretory recombinant brazzein.
• Purified brazzein using ultrafiltration with a molecular weight cutoff.

Main Results:

• Achieved high purity of secretory brazzein produced in the optimized defined medium compared to complex medium.
• Obtained a yield of approximately 107 mg L⁻¹ of purified brazzein.
• Reduced total media cost to approximately 11% of that for an optimized complex medium for equivalent brazzein production.

Conclusions:

• The Kluyveromyces lactis expression system with the optimized defined medium is effective for mass-producing high-purity recombinant brazzein.
• This system offers a significant reduction in production costs, making it promising for the food industry.
• The optimized process supports the potential of brazzein as a functional sweetener.