Exploiting new biorefinery models using non-conventional yeasts and their implications for sustainability

Area of Science:

• Biotechnology
• Microbiology
• Sustainable Chemistry

Background:

• Bioprocessing lignocellulosic biomass demands microbial strains resilient to inhibitors and osmotic stress.
• Efficient biomass conversion requires strains with high product yield and productivity for biorefinery applications.

Purpose of the Study:

• To evaluate Hansenula polymorpha CBS 4732 and Debaryomyces hansenii CBS 767 for lignocellulosic biomass conversion.
• To assess yeast capabilities in pentose and hexose sugar consumption, inhibitor tolerance, and production of sugar alcohols and ethanol.

Main Methods:

• Cultivation of H. polymorpha and D. hansenii under conditions simulating biomass hydrolysates.
• Analysis of sugar consumption (pentose and hexose), inhibitor tolerance, and product formation (sugar alcohols, ethanol).
• Comparative evaluation of the two yeast strains' performance at 37°C.

Main Results:

• H. polymorpha demonstrated significant tolerance to toxic compounds and efficient xylose consumption, producing xylitol and ethanol.
• D. hansenii excelled in producing arabitol from glucose.
• Both strains exhibited distinct metabolic capabilities relevant to biorefinery processes.

Conclusions:

• H. polymorpha and D. hansenii are promising candidates for sustainable biorefineries due to their unique traits.
• These findings advance the development of efficient lignocellulosic biomass conversion technologies.
• The study highlights the potential of non-conventional yeasts in industrial biotechnology.